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Balbharti Maharashtra State Board 12th Biology Important Questions Chapter 12 Biotechnology Important Questions and Answers.

Maharashtra State Board 12th Biology Important Questions Chapter 12 Biotechnology

Multiple Choice Questions

Question 1.
Recombinant DNA technique was established by ………………..
(a) Herbert Boyer
(b) Stanley Cohen
(c) Peter Lobban
(d) both (a) and (b)
Answer:
(d) both (a) and (b)

Question 2.
Modern biotechnology includes ………………..
(a) r-DNA technology and PCR
(b) microarrays, cell culture and fusion
(c) production of curds, cheese, wine
(d) both (a) and (b)
Answer:
(d) both (a) and (b)

Question 3.
How many of the following statements are correct with reference to electrophoresis.
1. DNA is positively charged and it moves towards the negative electrode.
2. DNA is negatively charged and it moves towards the anode.
3. Longer DNA fragments move faster during electrophoresis.
4. Shorter DNA fragments move slowly during electrophoresis.
(a) One
(b) TWo
(c) Three
(d) Four
Answer:
(a) One

Question 4.
PCR technique was developed by ………………..
(a) Stanley Cohen
(b) Herbert Boyer
(c) W. Arber
(d) K. Mullis
Answer:
(d) K. Mullis

Question 5.
……………….. technique is used for in vitro gene cloning or gene multiplication.
(a) Electrophoresis
(b) SDS-PAGE
(c) Spectroscopy
(d) PCR
Answer:
(d) PCR

Question 6.
During denaturation step of polymerase chain reaction, the reaction mixture is heated at ………………..
(a) 40-60°C
(b) 70-75°C
(c) 90-98°C
(d) 36°C
Answer:
(c) 90-98 °C

Question 7.
Annealing temperature of primer is ………………..
(a) 40-60°C
(b) 72°C
(c) 90-98°C
(d) 36°C
Answer:
(a) 40-60 °C

Question 8.
During PCR new strand of DNA is synthesized by ………………..
(a) thermostable Taq DNA polymerase
(b) ligase
(c) phosphorylase
(d) RE
Answer:
(a) thermostable Taq DNA polymerase

Question 9.
Restriction enzymes were discovered by ………………..
(a) K. Mullis
(b) S. Cohen
(c) H. Boyer
(d) Smith, Nathan and Arber
Answer:
(d) Smith, Nathan and Arber

Question 10.
The molecular scissors of DNA are ………………..
(a) ligases
(b) polymerases
(c) endonucleases
(d) transcriptases
Answer:
(c) endonucleases

Question 11.
……………….. generates DNA fragments with sticky ends.
(a) Eco RI
(b) Bam HI
(c) Hind II
(d) both (a) and (b)
Answer:
(d) both (a) and (b)

Question 12.
……………….. is Type III endonulcease.
(a) Hapal
(b) Eco R I
(c) Bgll
(d) Eco K
Answer:
(a) Hapal

Question 13.
Select the incorrect statement.
(a) Type II restriction endonucleases have separate activities for cleaving and methylation.
(b) Type I restriction endonucleases function simultaneously as endonuclease and methylase.
(c) Type II restriction endonucleases cut DNA at specific non-pallindromic sequences.
(d) Thousands of Type II restriction endonucleases have been discovered.
Answer:
(c) Type II restriction endonucleases cut DNA at specific non-palindromic sequences

Question 14.
Ti plasmids are present in ………………..
(a) Bacillus thuringiensis
(b) Agrobacterium tumejaciens
(c) Haemophilus influenza
(d) Escherichia coli
Answer:
(b) Agrobacterium tumefaciens

Question 15.
Plasmid DNA containing foreign DNA is called ………………..
(a) chimeric DNA
(b) passenger DNA
(c) recombinant DNA
(d) both (a) and (c)
Answer:
(d) both (a) and (c)

Question 16.
Bacterial host cell takes up naked r-DNA by process of ………………..
(a) transduction
(b) transfection
(c) transformation
(d) all of these
Answer:
(c) transformation

Question 17.
Virosomes are ………………..
(a) liposome
(b) inactivated HIV
(c) liposome + inactivated HIV
(d) none of these
Answer:
(c) liposome + inactivated HIV

Question 18.
Recombinant protein used in the treatment of emphysema is ………………..
(a) a 1-Antitrypsin
(b) relaxin
(c) Interleukin-1 receptor
(d) urokinase
Answer:
(a) a 1-Antitrypsin

Question 19.
Tissue plasminogen activator and urokinase are used in the treatment of ………………..
(a) blood clots
(b) atherosclerosis
(c) emphysema
(d) asthama
Answer:
(a) blood clots

Question 20.
Bacillus is involved in the production of ……………….. vaccine that melts in mouth.
(a) polio
(b) flu
(c) chicken pox
(d) none of these
Answer:
(b) flu

Question 21.
First transgenic plant produced is …………………..
(a) Bt cotton
(b) tlavr savr tomato
(c) wheat
(d) tobacco
Answer:
(d) tobacco

Question 22.
Insect resistant GMO plants contain ………………..
(a) cowpea trypsin inhibitor gene
(b) cry gene
(c) chalone isomerase gene
(d) (a) or (b)
Answer:
(d) (a) or (b)

Question 23.
‘Cry’ genes are present in ………………..
(a) Agrobacterium tumifaciens
(b) Bacillus thuringiensis
(c) Rhizobium species
(d) Escherichia coli
Answer:
(b) Bacillus thuringiensis

Question 24.
Crystals of Bt toxin produced by some bacteria do not kill the bacteria themselves because ………………..
(a) bacteria are resistant to toxin
(b) toxin is immature
(c) toxin is inactive
(d) bacteria encloses toxin in a special case
Answer:
(c) toxin is inactive

Question 25.
The gene coding for a-amylase inhibitor isolated from ……………….. is transferred to tobacco.
(a) mung bean
(b) adzuki bean
(c) E.coli
(d) daffodils
Answer:
(b) adzuki bean

Question 26.
The enzyme affecting the shelf life of Jlavr savr tomato is ………………..
(a) galactosidase
(b) transacetylase
(c) permease
(d) polygalactouranase
Answer:
(d) polygalactouranase

Question 27.
Ferritin, an iron storage protein, isolated from ……………….. and Phaseolus is transferred to ………………… to increase its iron content.
(a) soybean, rice
(b) rice, wheat
(c) maize, soybean
(d) rice, soybean
Answer:
(a) soybean, rice

Question 28.
To improve oil content and oil quality, ……………….. genes are transferred to soybean, oil palm, rapeseed and sunflower.
(a) Arabidopsis
(b) cry
(c) tobacco
(d) canola
Answer:
(a) Arabidopsis

Question 29.
Artemecin is an ……………….. drug developed from transgenic plants.
(a) anticancer
(b) antimalarial
(c) antibacterial
(d) antifungal
Answer:
(b) antimalarial

Question 30.
The transgenic cow born in Scotland, could produce a human protein in her milk for human therapeutics.
(a) Dolly
(b) Molly
(c) Tracy
(d) none of these
Answer:
(c) Tracy

Question 31.
Indian patent does not allow ………………..
(a) process patent
(b) product patent
(c) biopatent
(d) both (b) and (c)
Answer:
(b) product patent

Question 32.
Biopatent are awarded for ………………..
(a) strains of microbes and cell lines
(b) DNA sequences
(c) GMO
(d) All of these
Answer:
(d) All of these

Match the columns

Question 1.

Answer:

Question 2.

Answer:

Classify the following to form Column B as per the category given in Column A

(i) Provide tissues for human transplants
(ii) Cancer research
(iii) E. coli hygromycin resistant gene
(iv) Supply of factor IX.

Answer:

Very short answer questions

Question 1.
Who used the term biotechnology for the first time and for what purpose?
Answer:
Karl Ereky in 1919 first used the term biotechnology to describe a process for large scale production of pigs.

Question 2.
Which is the oldest form of biotechnology ?
Answer:
Making curds or bread is the oldest form of biotechnology. Preparation of wine and other alcoholic beverages using microbial fermentation is also old biotechnology.

Question 3.
Modern biotechnology is based on which two core techniques?
Answer:
Modern biotechnology is based on two core techniques – Genetic engineering and chemical engineering.

Question 4.
What is the use of Chemical engineering?
Answer:
Chemical engineering technology is used to maintain sterile environment for manufacturing products like vaccines, antibodies, enzymes, organic acids, vitamins, therapeutics, etc.

Question 5.
What are the different techniques used to characterize macromolecules on the basis of their molecular weight?
Answer:
The techniques used to characterize macromolecules on the basis of molecular weight are gel permeation, osmotic pressure, ion exchange chromatography, spectroscopy, mass spectrometry, electrophoresis, etc.

Question 6.
What are the different types of electrophoresis ?
Answer:
Different types of electrophoresis are agarose gel electrophoresis, PAGE (Polyacrylamide Gel Electrophoresis), SDS – PAGE (Sodium dodecyl Sulphate-PAGE).

Question 7.
What is the use of polymerase chain reaction?
Answer:
Polymerase chain reaction is used for in vitro gene cloning or gene multiplication to produce a billion copies of the desired segment of DNA and RNA, with high accuracy and specificity, in few hours.

Question 8.
What are the requirements of polymerase chain reaction?
Answer:
Polymerase chain reaction requires thermal cycler, DNA containing the desired segment to be amplified, deoxyribonuclueoside triphosphates (dNTPs), excess of two primer molecules, heat stable DNA polymerase and appropriate quantities of Mg⁺⁺ions.

Question 9.
Enlist various biological tools required for transformation of recombinant DNA?
Answer:
Biological tools used for transformation of recombinant DNA are enzymes, cloning vectors (vehicle DNA) and competent host (cloning organisms).

Question 10.
Enlist various enzymes used in recombinant DNA technology?
Answer:
Various enzymes used in recombinant DNA technology are lysozymes, nucleases (exonucleases, endonucleases, restriction endonucleases), DNA ligases, DNA polymerases, alkaline phosphatases, reverse transcriptases, etc.

Question 11.
How do bacteria protect their own DNA from restriction enzymes?
Answer:
The bacteria protect their own DNA from restriction enzymes by methylating the bases at susceptible sites. This chemical modification blocks the action of the enzyme.

Question 12.
What is restriction?
Answer:
Restriction is the process by which the DNA strand is cut into restriction fragments with the help of restriction endonuclease enzymes or REs.

Question 13.
What are molecular scissors? Why are they so called?
Answer:
The enzyme restriction endonucleases are called molecular scissors because they can cut the DNA molecule at a specific point.

Question 14.
What is palindrome in DNA?
Answer:
Palindrome is a DNA sequence which when read on opposite strands of DNA (3′ to 5′ or 5′ to 3′) it reads same.

Question 15.
What are sticky ends?
Answer:
Sticky ends are short extensions of cleaved DNA molecule which can form hydrogen bonded base pairs with other complementary sticky ends.

Question 16.
Give examples of restriction endo¬nucleases that cut DNA at non- pallindromic sequences.
Answer:
Hpal, MboII

Question 17.
Give example of Type I restriction endonucleases.
Answer:
Eco KI

Question 18.
Give example of Type II restriction endonucleases.
Answer:
Eco RI, Bg II

Question 19.
Give the role of plasmids in bacterial cells.
Answer:
Plamids in bacterial cells carry genes for antibiotic resistance (R plasmids) and F plasmids are involved in conjugation.

Question 20.
What are plasmids?
Answer:
The small, extra chromosomal double stranded, circular forms of DNA which are capable of autonomous replication are called plasmids.

Question 21.
What is the source of gene to be cloned in vector?
Answer:
Gene to be cloned is obtained from gene library or by amplification.

Question 22.
What is chimeric DNA?
Answer:
Chimeric DNA is the combination of vector DNA and foreign DNA.

Question 23.
What is meant by transformed cells?
Answer:
The competent host cells which have taken up r-DNA Eire called transformed cells.

Question 24.
What are the different techniques by which foreign DNA can be transferred to host cell without using a vector?
Answer:
Foreign DNA can be transferred to host cell without using a vector by techniques like electroporation, microinjection, lipofection, shot gun, ultrasonification, biolistic method, etc.

Question 25.
Which marker genes are present in plasmid PBR 322?
Answer:
Markers genes in PBR322 plasmid are ampicillin resistant gene and tatracyclin resistant gene.

Question 26.
What is c-DNA?
Answer:
DNA produced by reverse transcription of m-RNA is known as c-DNA.

Question 27.
What are the objectives of CCMB?
Answer:
The objectives of CCMB are to conduct high quality basic research and training in frontier areas of modern biology and promote centralized national facilities for new and modern techniques in the interdisciplinary areas of biology.

Question 28.
Give examples of health problems which develop due to interaction between genetic and environmental factors?
Answer:
Health problems like high cholesterol and high blood pressure develop due to interaction between genetic and environmental factors.

Question 29.
Give examples of diseases which are caused due to single gene defects.
Answer:
Human genetic diseases like sickle-cell anaemia, thalassemia, Tay-sach’s disease, cystic fibrosis, Huntington’s chorea, haemophilia, alkaptonuria, albinism, etc. . are caused by single gene defects.

Question 30.
What is gene therapy?
Answer:
Gene therapy is the treatment of genetic disorders by replacing, altering or supplementing a gene that is absent or abnormal and whose absence or abnormality is responsible for the disease.

Question 31.
What is the use of virosomes?
Answer:
Virosomes are used in gene delivery.

Question 32.
Enlist the diseases where clinical trials of somatic cell gene therapy have been employed?
Answer:
The clinical trials of somatic cell gene therapy have been employed for the treatment of disorders like cancer, rheumatoid arthritis, SCID, Gaucher’s disease, familial hypercholesterolemia, haemophilia, phenylketonuria, cystic fibrosis, sickle-cell anaemia, Duchenne muscular dystrophy, emphysema, thalassemia, etc.

Question 33.
Which gene codes for Bt toxin?
Answer:
‘Cry’ gene codes for Bt toxin.

Question 34.
The a-amylase inhibitor gene transferred to tobacco from azuki bean acts against which pests?
Answer:
The a-amylase inhibitor gene transferred to tobacco from azuki bean acts against Zabrotes subjasciatus and Callosobruchus chinensis.

Question 35.
Which gene has been introduced in j sugarbeet for synthesis of fructants?
Answer:
1-sucroese sucrose fructosyl transferase gene has been introduced in sugarbeet for synthesis of fructants.

Question 36.
What percent of world population is affected by iron deficiency?
Answer:
30% of the population is affected by iron deficiency.

Question 37.
What causes softening of tomatoes during ripening?
Answer:
The enzyme polygalacturonase in tomato, breaks down pectin in the middle lamella of cell wall. This results in softening of fruits J during ripening.

Question 38.
What is superglue?
Answer:
Superglue is a biochemical glue for body repairs during surgery.

Question 39.
How is superglue produced?
Answer:
Superglue is produced by tobacco plants which contain genes encoding for adhesive proteins which allow marine mussels to stick to rocks.

Question 40.
Which oncogenes are being analyzed in transgenic mice to find out their role in development of breast cancer?
Answer:
myc and ras oncogenes are being analyzed in transgenic mice to find out their role in development of breast cancer.

Question 41.
How much milk is provided by Holstein cow on an average?
Answer:
Holstein cow provides about 6000 litres of milk per year.

Question 42.
Which gene is introduced in sheep to increase meat production?
Answer:
Human growth hormone gene is introduced in sheep for promoting growth and meat production.

Question 43.
Enlist desirable traits present in transgenic chicken?
Answer:
Desirable traits in transgenic chicken are low levels of fat and cholesterol, high protein containing eggs, in vivo resistance to viral and coccidial diseases, better feed efficiency and better meat quality.

Question 44.
Clones of which animals can provide tissues and organs for human transplants?
Answer:
The pig clone can provide animal organs and tissues for human transplants (xenotransplantation).

Question 45.
Which genes have been introduced in transgenic fish?
Answer:
Transgenic fish are transfected with E.coli hygromycin resistance gene, growth hormone and chicken crystalline protein.

Question 46.
Why does the Indian Government has set up the Genetic Engineering Approval Committee (GEAC)?
Answer:
The Indian Government has set up the Genetic Engineering Approval Committee (GEAC) to make decisions regarding the validity of research involving GMOs and addresses the safety of GMOs introduced for public use.

Question 47.
What is the duration of a biopatent?
Answer:
Duration of biopatents is five years from the date of the grant or seven years from the date of filing the patent application, whichever is less.

Question 48.
What was the first biopatent awarded for?
Answer:
First biopatent was awarded for genetically engineered bacterium ‘Pseudomonas’ used for clearing oils spills.

Question 49.
What is Texmati?
Answer:
Texmati is a trade name of “Basmati rice line and grains” for which Texas based American company Rice Tec Inc was awarded a patent by the US Patent and Trademark Office (USPTO) in 1997.

Give definitions of the following

Question 1.
Biotechnology
Answer:
Biotechnology is defined as ‘the development and utilization of biological forms, products or processes for obtaining maximum benefits to man and other forms of life’.
OR
According to OECD (Organization for Economic Cooperation and Development, 1981), biotechnology is defined as the application of scientific and engineering principles to the processing of materials by biological agents to provide goods and service to the human welfare’.

Question 2.
Genetic engineering/r-DNA technology
Answer:
Genetic engineering is defined as the manipulation of genetic material towards a desired end and in a directed and predetermined way, using in vitro process.
OR
According to John E. Smith (1996), genetic engineering as ‘the formation of new combination of heritable material by the insertion of nucleic acid molecule produced by whatever means outside the cells, into any virus, bacterial plasmid or other vector system so as to allow their incorporation into a host organism in which they do not occur naturally but in which they are capable of continued propagation’.

Question 3.
Nucleases
Answer:
Enzymes that cut the phosphodiester bonds of polynucleotide chains are called as nucleases.

Question 4.
Vector
Answer:
Vectors are DNA molecules that carry a foreign DNA segment and replicate inside the host cell.

Question 5.
Plasmid
Answer:
Plasmids are small, extra chromosomal, double stranded circular forms of DNA that replicate autonomously.

Question 6.
Transformation
Answer:
Insertion of a vector into the target bacterial cell is called transformation. (Learn this as well)

Question 7.
Transfection
Answer:
Insertion of a vector into the eukaryotic cells is called transfection. (Learn this as well)

Question 8.
Transduction
Answer:
Inserting a viral vector in cloning procedures is called transduction. (Learn this as well)

Question 9.
Gene library
Answer:
Gene libarary is a collection of different DNA sequences from an organism where each sequence has been cloned into a vector for ease of purification, storage and analysis.

Question 10.
Genomic library
Answer:
Genomic library is a collection of clones that represent the complete genome of an organism.

Question 11.
c-DNA library
Answer:
c-DNA library is a collection of clones containing c-DNAs inserted into suitable vector like a phage or plasmid.

Question 12.
Passenger DNA
Answer:
Passanger DNA is the foreign DNA which is inserted into a cloning vector.

Question 13.
Gene therapy
Answer:
Gene therapy is the treatment of genetic disorders by replacing, altering or supplementing a gene that is absent or abnormal and whose absence or abnormality is responsible for the disease.

Question 14.
Genetically modified organisms
Answer:
Genetically modified organisms are those whose genetic material has been artificially manipulated in a laboratory through genetic engineering to create combinations of plant, animal, bacterial, and viral genes that do not occur in nature or through traditional crossbreeding methods.

Name the following

Question 1.
Restriction endonucleases which produce fragments with sticky ends.
Answer:
Bam HI and Eco RI.

Question 2.
Restriction endonucleases which produce fragments with blunt ends.
Answer:
Alu I, Hind III.

Question 3.
Most commonly used vectors.
Answer:
Plasmid vectors (pBR 322, pUC, Ti plasmid) and bacteriophages (lambda phage, M13 phage.

Question 4.
Bacteriophages used as vectors.
Answer:
Ml3, lambda virus

Question 5.
Constructed plasmids.
Answer:
pBR 322, pBR 320, pACYC 177

Question 6.
Most commonly used plasmid in r-DNA technology.
Answer:
pBR 322

Question 7.
Plasmid vector for plants.
Answer:
Ti plasmid

Question 8.
Soil bacterium that causes a plant disease called crown gall.
Answer:
Agrobacterlum tumejaciens

Question 9.
Bacteria as competent host.
Answer:
Bacillus Haemophilus, Helicobacter pyroli and E. coli.

Question 10.
Most commonly used host in transformation experiments.
Answer:
E. coli

Question 11.
Cloning organisms used in plant biotechnology.
Answer:
Agrobacterium tumejaciens.

Question 12.
Human protein produced by r-DNA technology to treat anaemia.
Answer:
Erythropoeitin

Question 13.
Human protein produced by r-DNA technology to treat asthma.
Answer:
Interleukin 1 receptor

Question 14.
Human protein produced by r-DNA technology to treat antherosclerosis.
Answer:
Platelet derived growth factor

Question 15.
Human protein produced by r-DNA technology to treat parturition.
Answer:
Relaxin

Question 16.
Human protein produced by r-DNA technology to treat cancer.
Answer:
Interferons, tumour necrosis factor, inter-leukins, macrophage activating factor.

Question 17.
Recombinant protein used in the treatment of haemophiliaA.
Answer:
Factor VIII

Question 18.
Recombinant protein used in the treatment of haemophiliaB.
Answer:
Factor IX

Question 19.
Transgenic food crop used to reduce vitamin A deficiency diseases.
Answer:
Golden rice

Question 20.
Human proteins expressed in cow milk.
Answer:
Human lactoferrin, human alpha lactalbumin, human serum albumin, human bile salt.

Question 21.
Bacterial genes concerned with biosynthesis of cystein.
Answer:
cys E, cys M

Question 22.
Transgenic fish.
Answer:
Atlantic salmon, catfish, goldfish, Tilapia, zebra-fish, common carp, rainbow trout.

Give significance or functions of the following

Question 1.
Transgenic plants.
Answer:

1. Transgenic plants Eire genetically engineered to carry various desirable traits.
2. They are resistant to bacterial and viral diseases (e.g. tomato, potato, etc), insect pests (Bt cotton), herbicides (e.g. maize and wheat) and abiotic stresses.
3. Transgenic plants can be used as bioreactors or factories (molecular farming) for production of novel drugs like interferons, humanized antibodies against infective agents like HIV, amino acids and immunotherapeutic drugs.
4. Some transgenic plants have improved nutritional qualities, e.g. golden rice and golden mustard are biofortified with vitamin A.
5. Transgenic plants like Flavr savr tomatoes have been engineered to have more shelf life.
6. Transgenic plants also produce edible vaccines, e.g. Potato, tomato, etc.

Question 2.
Transgenic animals.
Answer:

1. Transgenic animals are genetically modified animals that are used in a wide range of fields.
2. In the field of medical research, transgenic animals like mice are used to identify the functions of specific factors through over- or under-expression of a modified gene (the inserted transgene). They are designed to study how genes contribute to the development of disease. These animals are used to investigate development of diseases like cancer, cystic fibrosis, rheumatoid arthritis, etc.
3. In toxicology field, they are used for detection of toxicants. They are used as responsive test animals.
   Transgenic animals are used to evaluate a specific genetic change in molecular biology studies.
4. In pharmaceutical industry, transgenic animals are used for targeted production of pharmaceutical proteins, drug production and product efficacy testing.
5. They are also used in study of mammalian developmental genetics.

Transgenic farm animals like cattle, sheep, v poultry, pigs, etc. exhibit many desirable traits.

1. Improved quantity and quality of meat
2. Improved quality and quantity of milk
3. More egg production
4. Better quality and quantity of wool
5. Disease resistance
6. Production of low-cost pharmaceuticals and biologicals

Distinguish between the following

Question 1.
Old or classical biotechnology and Modem biotechnology.
Answer:

Question 2.
Genomic library and c-DNA library.
Answer:

Question 3.
Germ line gene therapy and somatic cell gene therapy.
Answer:

Give reason

Question 1.
The genetic engineering is alternatively called recombinant DNA technology or gene cloning.
Answer:

1. Genetic engineering involves the manipulation of genetic material in a directed, predetermined, in vitro way to develop a desired end product.
2. It manipulates the genes for improvement of living organisms,
3. It involves repairing of the defective genes, replacing of defective genes by healthy genes or normal genes and artificially synthesizing of a totally new gene.
4. Genetic engineering also involves transfer of a new gene, transfer of genes to a new location or into a new organism, gene cloning, combining of genes from two organisms.
5. This results in alteration of the genotype and desired products can be developed.
6. Therefore, the genetic engineering is alternatively called recombinant DNA technology or gene cloning.

Question 2.
Bacteria have restriction enzymes.
Answer:

1. Restriction endonucleases or restriction enzymes in bacteria help them to recognize and destroy various viral DNAs that might enter the cell.
2. They cut the phosphodiester back bone at highly specific sites on both strands of DNA.
3. Thus, these enzymes restrict the potential growth of the virus and protect bacteria.
4. Hence, bacteria produce restriction enzymes.

Question 3.
All the fragments of a genome are cloned for storing them in genomic library.
Answer:

1. Genomic DNA is fragmented at the time of preparing genomic library.
2. It is not known which fragment has the desired gene.
3. Therefore all the fragments have to be cloned to store the copies of each separately.
4. Screening for the desired gene is later done through complementation or using DNA probes.
5. Therefore, all the fragments of a genome are cloned for storing them in genomic library.

Question 4.
The establishment of genomic library is more meaningful in prokaryotes than in eukaryotes.
Answer:

1. The prokaryotic genome does not contain repetitive DNA.
2. Eukaryotic DNA genome contains introns, regulatory genes and repetitive DNA.
3. Hence, the establishment of genomic library is more meaningful in prokaryotes than in eukaryotes.

Question 5.
Flavr savr tomato has longer shelf life.
Answer:

1. Flavr savr is genetically modified type of tomato.
2. It is developed by inserting antisense gene which retards ripening.
3. Due to the presence of this gene a cell wall degrading enzyme called polygalactouronase is produced in lesser amounts.
4. Owing to the above reason, Flavr savr tomato has longer shelf life.

Question 6.
Pigs are regarded as the most suitable animals to be bred for heart transplant.
Answer:

1. A pig’s heart is about the same size as a human heart.
2. Pig heart valves are used in human heart surgery for over a decade.
3. Hence, pigs are regarded as the most suitable animals to be bred for heart transplant.

Question 7.
Patent jointly issued by Delta and Pineland Company and U. S. department of agriculture under the title ‘control of plant gene expression’ was not granted by Indian government.
Answer:

1. Patent jointly issued by Delta and Pineland Company and U. S. department of agriculture under the title ‘control of plant gene expression’ is based on a gene that produces a protein toxic to plant and thus prevents seed germination.
2. Because of such patents, financially powerful corporations would acquire monopoly over biotechnological process.
3. Thus it would pose a threat to global food security.
4. Therefore this patent was considered morally unacceptable and fundamentally unequitable and it was not granted by the Indian government.

Write short notes

Question 1.
Electrophoresis.
Answer:

1. Electrophoresis is a technique that involves migration and separation of charged particles under the influence of electric field.
2. It is used for the separation of charged molecules like DNA, RNA and proteins, by application of an electric field.
3. Movement of charged particles is determined by particle size, shape and charge.
4. DNA is negatively charged and hence it moves towards the positive anode.
5. It results in size separation of DNA fragments as small fragments of DNA molecules move faster.
6. Different types of electrophoresis are agarose gel electrophoresis, PAGE and SDA PAGE.

Question 2.
Recognition sequences or restriction sites.
Answer:

1. Restriction endonucleases have the ability to recognize specific sequences in DNA and cleave it.
2. They are 4 to 8 nucleotides long and characterized by a particular type of internal symmetry.
3. The specific site at which restriction endonuclease cuts the DNA is called recognition site or restriction site.
4. Each restriction endonuclease recognizes its specific recognition sequence.
5. Restriction cutting may result in DNA fragments with blunt ends or cohesive or sticky ends or staggered ends (having short, single stranded projections).

For example, recognition sequence of by the enzyme EcoRI is
3′ —– -CTTAA-G —–5′
5′ —– -G A A T T C —–3′
It is as palindrome, i.e. When read on opposite strand of DNA (3′ to 5′ or 5′ to 3′) it reads same.
When the enzyme EcoRI recognizes this sequence, it breaks each strand at the same site in the sequence i.e. between the A and G residues.

Question 3.
Plasmids as cloning vectors.
Answer:

1. Plasmids are small, extra-chromosomal, double stranded circular forms of DNA that replicate autonomously.
2. They are seen in bacterial cells, yeast and animal cell.
3. Plasmids are considered as replicons as they are capable of autonomous replication in suitable host.
4. The most commonly used vectors in r-DNA technology are plasmids as they replicate in E. coli.

Plasmid as a cloning vector should have a replication origin, a marker gene for antibiotic resistance, control elements like promoter, operator, ribosome binding site, etc. and a region where foreign DNA can be inserted. Naturally plasmids do not have all these features. Hence, they are constructed by inserting gene for antibiotic resistance. pBR 322, pBR320, paCYC177 are the constructed plasmids.

Ti plasmid (for tumor-inducing) of Agrobacterium tumefaciens is an important vector for carrying new DNA in many plants. It contains a transposon, called T DNA, which inserts copies of itself into the chromosomes of infected plant cells. The transposon, with the new DNA, can be inserted into the host cell’s chromosomes. A plant cell containing this DNA, can then be grown in culture or induced to form a new, transgenic plant.

Question 4.
Bt cotton.
Answer:

1. Bt cotton is well known example of insect resistant transgenic plant which is engineered with a gene from B. thuringiensis.
2. ‘cry’ gene present in B. thuringiensis produces a protein that forms crystalline inclusions in bacterial spores.
3. When insect ingests it, because of high pH and the proteinase enzymes present in insect’s midgut, the crystalline inclusions are hydrolyzed to release the core toxic fragments.
4. This toxin causes midgut paralysis and disruption of midgut cells of insect.
5. Bt toxin acts against many species of Lepidoptera, Diptera and Coleoptera insects.

Question 5.
Golden rice.
Answer:

1. Golden rice is a transgenic plant developed by Swiss researchers.
2. It contain genes from the soil bacterium Erwinia and either maize or daffodil plants.
3. These plants are biofortified to have high content of vitamin A.
4. The golden colour is due to vitamin A.
5. Consumption of golden rice and golden mustard can reduce occurrence of vitamin A deficiency diseases (VAD).

Question 6.
Insulin.
Answer:

1. Insulin is a peptide hormone produced by β -cells of islets of Langerhans of pancreas.
2. Insulin is essential for the control of blood sugar levels.
3. Disease Diabetes mellitus is caused due to inability to make insulin.
4. Insulin was discovered by Sir Edward Sharpey Schafer (1916) while studying Islets of Langerhans.
5. Hakura et al (1977) chemically synthesized DNA sequence of insulin for two chains A and B and separately inserted into two PBR322 plasmid vector.

Gilbert and Villokomaroff, 1978 produced insulin production using r-DNA technology.

1. The recombinant plasmids, containing insulin gene inserted by the side of β-galactosidase, were transferred into E. coli host.
2. The host produced penicillinase pnd pre-pro insulin.
3. Insulin is later separated by trypsin treatment.

Question 7.
Transgenic cattle.
Answer:

1. Transgenic cattle are used for food production and for the production of human therapeutic proteins.
2. Transgenic cattle engineered with additional copies of bovine beta or kappa casein, show 8 to 20% increase in beta casein and a two-fold increase in kappa casein.
3. Various human proteins like Human lactoferrin, human alpha lactalbumin, human serum albumin and human bile salt stimulated lipase are expressed in the milk of transgenic cattle.
4. Transgenic cows produce factor IX (plasma thromboplastin component), used in the treatment of haemophilia.
5. Tracy, the transgenic cow born in Scotland, could produce a human protein in her milk for human therapeutics.
6. Human antibody products are made using transgenic cows that are immunized with a vaccine containing the disease agent. Antibodies are currently used for treatment of infectious diseases, cancer, transplanted organ rejection, autoimmune diseases and for use as antitoxins.

Question 8.
Transgenic fish.
Answer:

1. The commercially important fish like Atlantic salmon, catfish, goldfish, Tilapia, zebra-fish, common carp, rainbow trout, etc. are transfected with growth hormone, chicken crystalline protein and E.coli hygromycin resistance gene.
2. Transgenic fish showed increased cold tolerance and improved growth.

Short Answer Questions

Question 1.
What are the two phases of the development of biotechnology in terms of its growth?
Answer:
Two phases of the development of biotechnology in terms of its growth are as follows:
Traditional biotechnology (old biotechnology) : It is based on fermentation technology that uses microorganisms in the preparation of curd, ghee, soma, vinegar, yogurt, cheese making, wine making, etc.

Modern biotechnology (new biotechnology) :

1. During 1970 ‘recombinant DNA technology was developed and then established by Stanley Cohen and Herbert Boyer in 1973.
2. This technique alters or modifies genetic material to develop of new products.
3. The combination of biology and production technology based on genetic engineering evolved into modern biotechnology.
4. Modern biotechnology is based on two core techniques-genetic engineering and chemical engineering.

Question 2.
What are the different techniques and devices used in r-DNA technology?
Answer:
(1) Several techniques are used in r-DNA technology to isolate and characterize the macromolecules like DNA, RNA, proteins.
(2) The techniques used on the basis of molecular weight are gel permeation, osmotic pressure, ion exchange chromatography, spectroscopy, mass spectrometry, electrophoresis, etc.

(3) Electrophoresis:

• It is used for the separation of charged molecules like DNA, RNA and proteins, by application of an electric field.
• Different types of electrophoresis : Agarose gel electrophoresis, PAGE, SDA PAGE.

(4) Polymerase chain reaction (PCR) : It is used for in vitro gene cloning or gene multiplication to produce a billion copies of the desired segment of DNA or RNA, with high accuracy and specificity, in few hours.

Question 3.
What are the basic requirements of PCR technique?
Answer:
The basic requirements of PCR technique are as follows:

1. DNA containing the desired segment to be amplified.
2. Excess of forward and reverse primers which are synthetic oligonucleotides of 17 to 30 nucleotide.
3. They are complementary to the sequences present in DNA.
   dNTPs which are of four types such as dATB dGTB dTTP and dCTR
4. A thermostable DNA polymerase (e.g. Taq DNA polymerase enzyme) that can withstand a high temperature of 90-98°C.
5. Appropriate quantities of Mg⁺⁺ ions.
6. Thermal cycler, a device required to carry out PCR reactions.

Question 4.
What are the two types of nucleases? What is their function?
Answer:

1. The two types of nucleases are exonucleases and endonucleases.
2. Exonucleases remove nucleotides from the ends of the DNA.
3. Endonucleases are those enzymes that have ability to make cuts at specific positions within the DNA molecule.
4. Of the endonucleases, restriction endonucleases serve as the molecular scissors in genetic engineering experiments.
5. They are used for cutting DNA molecules at specific predetermined sites. This is needed for gene cloning or recombinant DNA technology.

Question 5.
Explain different types of restriction enzymes?
Answer:
Different types of restrictions enzymes are as follows:

1. Type I – They function . simultaneously as endonuclease and methylase e.g. EcoK.
2. Type II – They exhibit separate cleaving and methylation activities. They are more stable and are used in r-DNA technology e.g. EcoRI, Bgll. They cut DNA at specific sites within the pallindrome. Thousands of type II restriction enzymes have been discovered.
3. Type III – They cut DNA at specific non- palindromic sequences e.g. Hpal, MboII.

Question 6.
With the help of a suitable example, illustrate palindrome.
Answer:

1. Palindrome is a sequence which when read on opposite strands of DNA (3′ to 5’ or 5’ to 3’), reads same.
2. When the enzyme EcoRI recognizes this sequence, it breaks each between the A and G residues.
3. In palindrome, the base sequence of second half in DNA represents the mirror image of the base sequence of the first half.
4. Palindromes are actually groups of letters which form the same word when read in both forward and backward directions.

For example, recognition sequence of by the enzyme EcoRI is a palindrome.
3′ —— – C T T A A G—–5′
5′ —— – G A A T T C—–3′

Same restriction enzyme must be used to cut vector and donor DNA, because it will produce fragments with the same complementary sticky ends, making it bond formation possible between them.

Question 7.
Explain how Ti plasmid of Agrobacterium tumefaciens acts as a vector for transferring genes to plants?
Answer:

1. Agrobacterium tumefaciens is a soil bacterium that causes crown gall disease in plants.
2. This disease involves the formation of tumor in the plant.
3. Ti plasmid in A. tumefaciens contains a transposon called T DNA.
4. T DNA inserts copies of itself into the chromosomes of infected plant cells.
5. The transposons, with the foreign DNA, can be inserted into the host cell’s chromosomes.
6. A plant cell containing this DNA, can then be grown in culture or induced to form a new, transgenic plant.

construction of Genomic library:

1. When genomic library is constructed, the entire genome or DNA is isolated from a particular organism.
2. This DNA is fragmented using suitable restriction endonucleases.
3. These separated fragments are later inserted into cloning vectors.
4. This develops recombinant vectors.
5. Such recombinant vectors are transferred into suitable organisms such as bacteria or yeast. Each host cell then contains one fragment.
6. These transformed organisms are cultured and their clones are thus produced. These clones are stored in the genomic library.

Question 8.
Explain with example how transformed host cells are selected from non- transformed?
Answer:

1. Transformed recombinant cells are selected using marker genes.
2. For example, markers genes in pBR 322 plasmid are ampicillin resistant gene and tetracyclin resistant gene.
3. When pstl restriction enzyme is used, ampicillin resistant gene gets knocked off from the plasmid and recombinant cells become sensitive to ampicillin.

Question 9.
Give the types of human proteins and hormones produced by recombinant DNA techniques.
Answer:

1. Blood proteins produced by recombinant DNA technique are Erythropoeitin, Tissue plasminogen activator, urokinase, Factor VIII, Factor IX, etc.
2. Hormones : Insulin, Epidermal growth factor.

Question 10.
What are edible vaccines? How are they produced?
Answer:

1. Edible vaccine is an edible plant part engineered to produce an immunogenic protein, which when consumed gets recognized by immune system.
2. Immunogenic protein of certain pathogens are active when administered orally.
3. The gene encoding for immunogenic protein is isolated and inserted in a suitable vector.
4. Recombinant vector is then transferred to plant genome.
5. Expression of this gene in specific parts of the plant results in the synthesis of immunogenic proteins.
6. When animals or mainly humans consume these plant parts, they get vaccinated against certain pathogen.

Question 11.
Give an example of ‘melt in mouth’ vaccine and state the advantages of such vaccines.
Answer:

1. Example of ‘melt in the mouth’ vaccine that can be administered by placing it under tongue, is the production of flu vaccine by Bacillus which melts in the mouth and get delivered into the blood stream.
2. Advantages of edible oral vaccines are that they can be easily administered, can be easily stored and they are of low cost.

Question 12.
What is meant by recalcitrant seeds? How such plants can be conserved?
Answer:

1. Recalcitrant seeds are those whose survival is educed upon drying (reduction in moisture below a certain level) and freezing and thus are difficult to store.
2. It involves subcellular damage of seeds which results in loss of viability, when dried.
3. Plants which produce recalcitrant sees could be conserved using tissue culture technique.

Question 13.
What are the different ways in which gene therapy is used?
Answer:
Gene therapy is being used as follows:

1. Replacement of missing or defective genes.
2. Delivery of genes that speed the destruction of cancer cells.
3. Supply of genes that cause cancer cells to revert back to normal cells.
4. Delivery of bacterial or viral genes as a form of vaccination.
5. Delivery of DNA to antigen expression and generation of immune response.
6. Supply of gene for impairing viral replication.
7. Provide genes that promote or impede the growth of new tissue.
8. Deliver genes that stimulate the healing of damaged tissue.

Question 14.
What are the different types in which genes could be delivered during gene therapy?
Answer:
Genes can be delivered by three ways:

1. Ex vivo delivery : In this type of gene delivery, viral or non-viral vectors are used to introduce the desired gene in the cells isolated from patient, e.g. Parkinson’s disease, a neurological disorder.
2. In vivo delivery : In this method, therapeutic genes are directly delivered at the target sites of the cells of diseased tissue. Intravenous infusion genes are injected directly into tumor in the treatment of cancer.
3. Use of virosomes (Liposome + inactivated HIV), bionic chips.

Question 15.
What are transgenic plants? Explain with any two examples.
Answer:
The genetically engineered crop plants carrying desirable traits are called transgenic plants.
Examples of transgenic plants:

1. Bt Cotton : Bt cotton is a transgenic plant. Bt toxin gene has been cloned and introduced in many plants to provide resistance to insects without the need of insecticides.
2. Golden rice : It is a genetically engineered rice with higher beta carotene (provitamin A) content.
3. Flavr savr tomato : It is developed by inhibiting synthesis of polygalactournonase by inserting antisense gene. This type of tomato has a longer shelf life.

Question 16.
Give any two examples of insect resistant transgenic crops.
Answer:
Examples of insect resistant transgenic crops are as follows:
(1) BT crops:

• Insect resistant transgenic plants contain either a gene from B. thuringiensis or the cowpea trypsin inhibitor gene.
• ‘cry’ gene present in B. thuringiensis produces a protein that forms crystalline inclusions in bacterial spores. When insect ingests it, because of high pH and the proteinase enzymes present in insect’s midgut, they are hydrolyzed to release the core toxic fragments.
• This toxin causes midgut paralysis and disruption of midgut cells of insect.
• Bt toxin activity has been against many species of insects within the orders of Lepidoptera, Diptera and Coleoptera.

(2) Transgenic tobacco:

• The gene of a-amylase inhibitor (aAl-Pv), isolated from adzuki bean (Phaseolus vulgaris) is transferred to tobacco.
• This gene works against pests like Zabrotes subfasciatus and Callosobruchus chinensis.

Question 17.
Give any two examples of biofortified transgenic crops.
Answer:
Examples of biofortified transgenic crops are as follows:

1. Golden rice and Golden mustard These are transgenics rich in vitamin A.
2. Arabidopsis genes are transferred to soybean, oil palm, rapeseed and sunflower for improvement in oil content and oil quality.
3. Ferritin, an iron storage protein, isolated from soybean and Phaseolus is transferred to rice to increase its iron content.
4. Plants deficient in amino acids like methionine, lysine and tryptophan have been engineered to improve protein content.

Question 18.
What factors are responsible for losses during storage and transport of crops? Explain, with example, how genetic engineering can reduce these losses?
Answer:

1. Diseases and pests, bruising on soft fruits and vegetables, heat and cold storage, over-ripeness, loss of flavours and odours, etc. lead to great deal of losses during storage and transport of crops.
2. Most of these changes are caused due to endogenous enzyme activities which could be slowed down using genetic engineering.

For example, shelf life of Flavr savr tomatoes has been increased using genetic engineering techniques.
(a) The enzyme polygalacturonase breaks down pectin in the cell wall, leading to softening of fruit during ripening of tomatoes.
(b) In genetically modified Flavr savr tomatoes, polygalactouronase enzyme is inhibited by antisense genes. These tomatoes can remain on the vine until mature and be transported in a firm solid state.

Question 19.
How transgenic animals are produced.?
Answer:

1. Transgenic animals are produced using recombinant DNA technology.
2. Foreign DNA is introduced in transgenic animals using r-DNA technology.
3. It is then transmitted through the germ line so that every cell if the animal contains the same modified genetic material.
4. This involves cloning of desired gene and introduction of cloned gene into fertilized eggs, successful implantation of modified eggs into receptive female and obtaining progeny carrying cloned genes.

Question 20.
Write any two scientific and commercial values of transgenic animals in favour of human beings.
Answer:
(1) Scientific value of transgenic animals:

• Transgenic mice are used medical research to identify the functions of specific factors through over – or under-expression of a modified gene (the inserted transgene). They are designed to study how genes contribute to the development of disease. These animals are used to investigate development of diseases like cancer, cystic fibrosis, rheumatoid arthritis, etc.
• In toxicology field, they are used for detection of toxicants. They are used as responsive test animals.

(2) Commercial value of transgenic animals:

• Transgenic cattle are used for production of human therapeutic proteins such as human lactoferin, human serum albumin, etc.
• Better quality and quantity of wool by transgenic sheep.

Question 21.
How sheep are genetically altered to produce wool of better quality?
Answer:

1. Bacterial genes, cys E and cys M, are identified, cloned and introduced in sheep.
2. These genes are involved in biosynthesis of cysteine.
3. Cysteine is involved in formation of keratin protein found in wool.
4. Thus, transgenic sheep produce more quantity and better quality of wool.

Question 22.
What is meant by ethics?
Answer:

1. Ethics is a discipline concerned with moral values or principles.
2. It deals with certain sets of standards which regulate behaviour of community.
3. It is concerned with socially accepted norms of moral duty, conduct and judgment.
4. Ethical concepts differ according to culture and traditions.
5. They also change with time and get influenced by progress in science and technology.

Question 23.
What are the adverse effects of Biotechnology on the Environment?
Answer:
The adverse effects of biotechnology on the environment are as follows:

1. Unintended hybrid strains of weeds and other plants can develop resistance to herbicides through cross-pollination. E.g. Crops of Round Up-ready soybeans which are used in agriculture, possibly confer Round Up resistance to neighbouring plants.
2. Bt corn has adversely affected non target species – Monarch butterfly. It may also prove harmful to neutral or even beneficial species.

Question 24.
Discuss various health concerns regarding the use of GMO crops.
Answer:
Various concerned related to health regarding the use of GMO crops are as follows:

1. GMO crops may develop some allergies, e.g. A gene from the Brazil nut was transferred to soybean in order to increase methionine content. But this transgenic soybean has caused allergies in some people which are known to suffer from nut allergies (“Biotech Soybeans”).
2. GMO technology is a recent development and its the long-term effects on health cannot be anticipated at this point.
3. Potential effects of transgenic proteins, which were never been ingested earlier, on the human body are yet unknown.
4. The use of GMOs may lead to the development of antibiotic and vaccine- resistant strains of diseases.

Question 25.
What is a patent?
Answer:

1. Patent is a special right granted to the inventor by the government.
2. A patent consists of three parts – grant (an agreement with the inventor), specification (subject matter of invention) and claims (scope of invention to be protected).
3. Patent is a personal property of inventor and it can be sold like any other property.

Question 26.
What is meant by traditional knowledge? What is its importance?
Answer:

1. Traditional knowledge is a deep understanding of ecological processes and the ability to obtain useful products from the local habitat in a sustainable way.
2. Most traditional knowledge is handed down through generations. This helps in the development of modern, commercial applications. This saves the makers time, money and effort.

Traditional knowledge includes:

1. Knowledge about food, crop varieties and agricultural/farming practice.
2. Sustainable management of natural resources and conservation of biological diversity.
3. Biologically important medicines.

Chart or Table based Questions

Question 1.

Answer:

Question 2.

Answer:

Question 3.

Answer:

Diagram Based Questions

Question 1.
(a) Name the reaction shown in the given diagram.
(b) What are the three steps in this reaction?
Answer:

(a) Polymerase chain reaction
(b) Three steps of polymerase chain reaction are denaturation of DNA, annealing of primer and extension of primer.

Question 2.
(a) Which enzyme has recognition sequence shown in the diagram given below?
(b) What is meant by palindrome?
(c) Enzyme in the given diagram cuts DNA to produce ———- ends.

Answer:
(a) Enzyme is EcoRI.
(b) Palindrome is a DNA sequence which when read in opposite direction (3’ to 5’ or 5’ to 3’) it reads same.
(c) Enzyme in the given diagram cuts DNA to produce sticky ends.

Question 3.
Draw a labelled diagram of a plasmid showing ori, ampr and a region into which foreign DNA can be inserted.
Answer:

Question 4.
Draw a diagram showing steps in r-DNA technology.
Answer:

Long Answer Questions

Question 1.
Explain with examples how transgenic plants can be used as factories or bioreactors?
Answer:

1. Transgenic plants are potential factories or bioreactors for biochemicals and biopharmaceuticals like starch, sugar, lipids, proteins, hormones, antibodies, vaccines or enzymes.
2. Various fine chemicals, perfumes, adhesive compounds industrial lubricants, etc. can be isolated from plants.
3. Plants can be the source of biodegradable plastic and ‘renewable’ energy to replace fossil fuels.
4. Transgenic plants useful for production of novel drugs like interferons, edible vaccines, antibodies, amino acids, immunotherapeutic drugs, etc. Thus, they are like bioreactors for molecular farming.

Examples:

1. The gene for Human growth hormone has been inserted into the chloroplast DNA of tobacco plants.
2. Humanized antibodies against HIV, Respiratory syncytial virus (RSV), Herpes simplex virus (HSV), the cause of “cold sores” are developed using transgenic plants.
3. Superglue’ is a biochemical glue for body repairs during surgery. It is produced by tobacco plants which contain genes encoding for adhesive proteins which allow marine mussels to stick to rocks.
4. Protein antigens to be used in vaccines : e.g. Patient-specific antilymphoma vaccines. B-cell lymphomas are clones of malignant B cells expressing a unique antibody molecule on their surface.
5. Transgenic plants cam be used as factories for producing oil having nutritional value like cod-liver oil. These plants are engineered with a oil encoding gene from marine algae.
6. Transgenic plants produce the antimalarial drug, Artemisinin.
7. Genetically engineered opium poppy can be used to produce powerful painkillers.
8. Transgenic plants like potatoes, tomatoes, bananas, soybeans, alfalfa and cereals can be used as edible vaccine.

Balbharti Maharashtra State Board 12th Biology Important Questions Chapter 11 Enhancement of Food Production Important Questions and Answers.

Maharashtra State Board 12th Biology Important Questions Chapter 11 Enhancement of Food Production

Multiple Choice Questions

Question 1.
Means of in situ germplasm conservation are ………………….
(a) forests
(b) Natural Reserves
(c) botanical gardens, seed banks
(d) both (a) and (b)
Answer:
(d) both (a) and (b)

Question 2.
Means of ex situ germplasm conservation are ………………….
(a) forests and seed banks
(b) natural Reserves
(c) botanical gardens, seed banks
(d) botanical garden and forests
Answer:
(c) botanical gardens, seed banks

Question 3.
Germplasm includes ………………….
(a) only improved varieties of crop
(b) all cultivated varieties and wild relatives of a particular crop
(c) all hybridized varieties only
(d) only mutant varieties of a crop
Answer:
(b) all cultivated varieties and wild relatives of a particular crop

Question 4.
Taichung Native-1 is a variety of rice from ………………….
(a) China
(b) Korea
(c) Malaysia
(d) Taiwan
Answer:
(d) Taiwan

Question 5.
Which of the following is not a fungal disease ?
(a) Late blight of potato
(b) Brown rust of wheat
(c) Red rot of sugar cane
(d) Black rot of crucifers
Answer:
(d) Black rot of crucifer

Question 6.
…………………. variety of wheat is resistant to Hill bunt disease.
(a) Himgiri
(b) Pusa swarnim
(c) Kalyan sona
(d) Pusa A-4
Answer:
(a) Himgiri

Question 7.
Regina-II variety of …………………. is resistant to bacterial rot.
(a) wheat
(b) cabbage
(c) cauliflower
(d) Brassica
Answer:
(b) cabbage

Question 8.
The nectar-less cotton having smooth leaves has resistance against ………………….
(a) bollworms
(b) jassids
(c) aphids
(d) stem borers
Answer:
(a) bollworms

Question 9.
………………… gave concept of in vitro cell culture.
(a) Haberlandt
(b) Frank
(c) Yabuta and Sumiki
(d) None of these
Answer:
(a) Haberlandt

Question 10.
Tissue culture requirements are ………………….
(a) pH of nutrient medium 5 to 5.8
(b) Sterilized glassware, nutrient medium, explants, inoculation chamber
(c) Temperature 18 °C to 20 °C
(d) All of these
Answer:
(d) All of these

Question 11.
Hybrid maize with double the quantity of amino acids …………………. have been developed.
(a) lysine and tryptophan
(b) alanine and aspartic acid
(c) glutamic and proline
(d) histidine and cystine
Answer:
(a) lysine and tryptophan

Question 12.
Inbreeding increases ………………….
(a) homozygosity
(b) heterozygosity
(c) heterosis
(d) hemizygosity
Answer:
(a) homozygosity

Question 13.
Which hormone is used for MOET method?
(a) GH
(b) LH
(c) FSH
(d) ICSH
Answer:
(c) FSH

Question 14.
Find the odd one out.
(a) Sahiwal
(b) Sindhi
(c) Gir
(d) Holstein
Answer:
(d) Holstein

Question 15.
Pullorum is a …………………. disease.
(a) viral
(b) bacterial
(c) fungal
(d) parasitic
Answer:
(b) bacterial

Question 16.
Propolis is ………………….
(a) bee glu
(b) royal jelly
(c) bee venom
(d) none of these
Answer:
(a) bee glu

Question 17.
Select the incorrect pair.
(a) Apis dorsata – Rock bee
(b) Apis indica -Indian bee
(c) Apis florae – Little bee
(d) Apis mellifera – Wild bee
Answer:
(d) Apis mellifera – Wild bee

Question 18.
fishery takes place in Sundarban area of ………………….
(a) Estuarine, West Bengal
(b) Marine, Odisha
(c) Fresh water, West Bengal
(d) None of these
Answer:
(a) Estuarine, West Bengal

Question 19.
Which stage in the life cycle of silk moth secretes silk?
(a) Caterpillar
(b) Egg
(c) Pupa
(d) Adult
Answer:
(a) Caterpillar

Question 20.
Lac insect is a native of ………………….
(a) China
(b) India
(c) Africa
(d) Europe
Answer:
(b) India

Question 21.
Alcoholic fermentation is brought about by ………………….
(a) Lactobacillus
(b) Saccharomyces
(c) Trichoderma
(d) Streptomyces
Answer:
(b) Saccharomyces

Question 22.
…………………. and …………………. are alcoholic beverages produced without distillation.
(a) Wine, rum
(b) Wine, beer
(c) Whisky, brandy
(d) Brandy, beer
Answer:
(b) Wine, beer

Question 23.
Organic acid can be produced directly from glucose or formed as end products from ………………….
(a) pyruvate
(b) ethanol
(c) gluconic acid
(d) both (a) and (b)
Answer:
(d) both (a) and (b)

Question 24.
The microbial source of vinegar is ………………….
(a) Aspergillus niger
(b) Rhizopus arrhizus
(c) Acetobacter aceti
(d) Streptomyces venezuelae
Answer:
(c) Acetobacter aceti

Question 25.
Statins are produced by ………………….
(a) Monascus purpureus
(b) Streptococcus
(c) Aspergillus niger
(d) None of these
Answer:
(a) Monascus purpureus

Question 26.
…………………. is used as a ‘clot buster’.
(a) Pectinase
(b) Statin
(c) Invertase
(d) Streptokinase
Answer:
(d) Streptokinase

Question 27.
Aspergillus niger is used to manufacture ………………….
(a) pectinase, gluconic acid and vitamin C
(b) pectinase, gluconic acid and vitamin B₁₂
(c) invertase, acetic acid and vitamin C
(d) pectinase, citric acid and invertase
Answer:
(a) pectinase, gluconic acid and vitamin C

Question 28.
The first Gibberellin was isolated by ………………….
(a) Frank
(b) Skoog
(c) Yabuta and Sumiki
(d) None of these
Answer:
(c) Yabuta and Sumiki

Question 29.
Once the BOD of waste water is reduced, it is passed into a ………………….
(a) settling tank
(b) primary sedimentation tank
(c) anaerobic sludge digesters
(d) aeration tank
Answer:
(a) settling tank

Question 30.
During biogas production species used to bring about hydrolysis or solubilization is ………………….
(a) Pseudomonas
(b) Rhizopus
(c) Methanococcus
(d) Methanobacillus
Answer:
(a) Pseudomonas

Question 31.
…………………. bacteria are used as herbicides.
(a) Pseudomonas spp., Xanthomonas spp., Agrobacterium spp.
(b) Bacillus thuringiensis, B. papilliae, B. lentimorbus
(c) Pseudomonas spp., Bacillus thuringiensis, B. papilliae
(d) Xanthomonas spp., Agrobacterium spp., Bacillus thuringiensis
Answer:
(a) Pseudomonas spp., Xanthomonas spp., Agrobacterium spp.

Question 32.
The weed Senecio jacobeac is controlled by ………………….
(a) Cactoblastis cactorum
(b) Xanthomonas spp
(c) Bacillus thuringiensis
(d) tyrea moth
Answer:
(d) tyrea moth

Question 33.
Nosema locustae is …………………. pathogen.
(a) bacteria
(b) fungal
(c) protozoan
(d) viral
Answer:
(c) protozoan

Question 34.
Which of the following bacterial pathogen is not used as herbicide ?
(a) Pseudomonas
(b) Xanthomonas
(c) Agrobacterium
(d) Azotobacter
Answer:
(d) Azotobacter

Question 35.
Identity free living bacterial biofertlizer ………………….
(a) Rhizobium
(b) Azotobacter
(c) Nostoc
(d) Bacillus thuringiensis
Answer:
(b) Azotobacter

Question 36.
The ectomycorrhizae form …………………. on the root surface.
(a) root tuber
(b) mantle
(c) root hair
(d) arbuscles
Answer:
(b) mantle

Match the columns

Question 1.

Answer:

Question 2.

Answer:

Classify the following to form Column B as per the category given in Column A.

Question 1.
i. Alternaria crassa
ii. Agrobacterium spp.
iii. Cactoblastis cactorum
iv. Beavueria bassiana

Answer:

Question 2.
i. Hairy leaves in wheat
ii. Nectar-less cotton having smooth leaves
iii. Hairy leaves in cotton
iv. Solid stem in wheat

Answer:

Very Short Answer Questions

Question 1.
What are the different methods of plant breeding?
Answer:
Different methods of plant breeding are introduction, selection, hybridization, mutation breeding, polyploidy breeding, tissue culture, r-DNA technology and SCP (Single cell protein).

Question 2.
Which variety of sugar cane having high sugar content and better yield is cultivated in South India?
Answer:
Saccharum ojficinarum variety of sugar cane has high sugar content and better yield. It is cultivated in South India.

Question 3.
What are the desirable characteristics in hybrid varieties millets developed in India?
Answer:
Hybrid varieties of millets developed in India are high yielding and resistant to water stress.

Question 4.
Give examples of natural physical mutagens.
Answer:
Natural physical mutagens are high temperature, high concentration of CO₂, X-rays, UV rays.

Question 5.
Give examples of chemical mutagens.
Answer:
Chemical mutagens are nitrous acid, EMS (Ethyl – Methyl – Sulphonate), mustard gas, colchicine, etc.

Question 6.
How are seedlings or seeds mutated?
Answer:
Seedlings or seeds are mutated by irradiating them by CO-60 or exposing them to UV bulbs, X-ray machines, etc.

Question 7.
What are the effects of mutagens?
Answer:
Effects of mutagens are gene mutations and chromosomal aberrations.

Question 8.
Which biochemical characters are responsible for resistance against stem borers in maize?
Answer:
High aspartic acid, low nitrogen and sugar content are responsible for resistance against maize stem borers.

Question 9.
What does the plant tissue culture medium consists of?
Answer:
The plant tissue culture medium consists of water, all essential minerals, sources for carbohydrates, proteins and fats, growth hormones like auxins and cytokinins, vitamins. Agar is added to solidify nutrient medium for callus culture.

Question 10.
What are the types of tissue culture based on nature of explants?
Answer:
Cell culture, organ culture, pollen or anther culture, meristem culture and embryo culture are the types of tissue culture based on nature of explants.

Question 11.
What are the types of tissue culture based on the type of in vitro growth?
Answer:
Callus culture and suspension culture are the type of tissue culture based on the type of in vitro growth.

Question 12.
What is the necessity of subculturing?
Answer:
Both the callus and suspension cultures die in due course of time when nutrients get consumed. Therefore, a part of callus or suspension of cells is transferred to the flask containing new nutrient medium. This is subculturing, which is necessary to ensure continuous nutrient supply essential for continuous growth.

Question 13.
Enlist substances that are used as substrate for the production of SCP.
Answer:
Agricultural waste like corn cobs, sugar cane molasses, wood shavings, sawdust, paraffin, N-alkanes, human and animal wastes are the substrates used for the production of SCR.

Question 14.
How biofortified crops are produced?
Answer:
Biofortified crops are produced by conventional selective breeding practices and r-DNA technology.

Question 15.
What per cent of world livestock population is present in India and China and what is the productivity?
Answer:
India and China have 70% of world livestock populations, but the productivity is only 25% of the world farm produce.

Question 16.
What is silage made up of?
Answer:
Silage is fermented fodder made up of legumes, grasses, maize and jowar.

Question 17.
What is the supplementary food to silage?
Answer:
Silage is supplemented with oilcakes, minerals, vitamins and salts.

Question 18.
What is layer?
Answer:
The hen which is reared to obtain eggs is called a layer.

Question 19.
What is broiler?
Answer:
The hen which is reared to obtain meat is called a broiler.

Question 20.
What are the allied professions to poultry?
Answer:
The allied professions to poultry are processing of eggs and meat, marketing of poultry products, compounding and sale of poultry feed, poultry equipment, pharmaceuticals, feed additives, etc.

Question 21.
Which areas are suitable for bee keeping?
Answer:
The areas having sufficient wild shrubs, cultivated crops of sunflower, mustard, safflower, chilly, cabbage, cucumber, legumes, etc. and fruit orchards of apple, mangoes, citrus, etc. are suitable for bee keeping.

Question 22.
What is indicated by yellow spots?
Answer:
Yellow spots indicate shrinking of female lac insect.

Question 23.
What is indicated by orange spots on the eggs of lac insect?
Answer:
Orange spots indicate that eggs are about to hatch.

Question 24.
What is the main function of a fermenter?
Answer:
The main function of a fermenter is to provide a controlled environment for growth of specific microorganisms or a defined mixture of microorganisms, to obtain the desired product.

Question 25.
What is known as Brewer’s yeast?
Answer:
Saccharomyces cerevisiae var. ellipsoids is commonly known as Brewer’s yeast.

Question 26.
Which fermenter is used for large scale preparation of alcohol?
Answer:
Tubular tower fermenter is used for large scale preparation of alcohol.

Question 27.
What is the use of gluconic acid?
Answer:
Gluconic acid is used in medicine for solubility of Ca⁺⁺

Question 28.
What is the use of citric acid?
Answer:
Citric acid is used in confectionary.

Question 29.
What is the use of fumaric acid?
Answer:
Fumaric acid is used in resins as wetting agents.

Question 30.
Give examples of diseases which are treated using antibiotics.
Answer:
Diseases like plague, whooping cough, diphtheria and leprosy are treated using antibiotics.

Question 31.
What is the mechanism of actions of statins?
Answer:
Statins produced by yeast Monascus purpureus are blood cholesterol lowering agents. They are competitive inhibitors of the enzyme that catalyzes synthesis of cholesterol.

Question 32.
Enlist the various enzymes produced using microorganisms.
Answer:
Amylase, cellulase, protease, lipase, pectinase, streptokinase, invertase enzymes are produced using microorganisms.

Question 33.
Gibberellin was first isolated from which plant?
Answer:
Gibberellin was first isolated from rice plant infected by fungus Gibberella Jujikuroi.

Question 34.
How many different types of Gibberellins have been isolated?
Answer:
About 15 different types of Gibberellins have been isolated.

Question 35.
Give the chemical composition of biogas.
Answer:
The biogas consists of methane (50-60%), CO₂ (30 to 40%), H₂S (0-3%) and other gases like CO, N₂, H₂ in traces.

Question 36.
Which substrates are used for biogas production?
Answer:
Substrates like cattle dung (most commonly used substrate, a rich source of cellulose from plants), plant wastes, animal wastes, domestic wastes, agriculture waste, municipal wastes, forestry wastes, etc. are used for biogas production.

Question 37.
Which are the most commonly used models of biogas plants ?
Answer:
Models of biogas plants developed by KVTC (Khadi and Village Industries Commission) and IARI (Indian Agricultural Research Institute) are the most commonly used in India.

Question 38.
Which bacteria transform acetic acid into biogas?
Answer:
The acetic acid is transformed into biogas by methanogenic bacteria like Methanococcus, Methanobacterium and Methanobacillus.

Question 39.
What are the four groups of biocontrol agents?
Answer:
The four groups of biocontrol agents are bacteria, fungi, viruses and protozoans.

Question 40.
What is mycoherbicide ?
Answer:
The pathogenic fungus which kills or inhibits the growth of a weed is called mycoherbicide.

Question 41.
What are the three types of bacterial biofertilizers on the basis of function?
Answer:
On the basis of function, bacterial biofertilizers are of three types – nitrogen fixing, phosphate solubilizing and compost making biofertilizers.

Question 42.
What are the eight different types of mycorrhiza as per recent classification?
Answer:
Nowadays, mycorrhiza are classified into 8 different types – ectomycorrhizae, endomycorrhizae, ectendomycorrhizae, orchidaceous mycorrhizae, ericoid mycorrhizae, arbutoid mycorrhizae, monotrapoid mycorrhizae and ophioglossoid mycorrhizae.

Question 43.
What is heterocyst?
Answer:
Cynobacteria possess specialized colourless cells called heterocysts which are the sites of nitrogen fixation.

Question 44.
Give the role of heterocyst.
OR
Give the importance of heterocyst in cyanobacteria.
Answer:
The heterocysts are the sites of nitrogen fixation in cyanobacteria.

Question 45.
Who discovered mycorrhizae?
Answer:
Mycorrhizae were discovered by Frank (1885).

Give definitions of the following

Question 1.
Food
Answer:
Food is defined as solid or liquid substance, which is swallowed, digested and assimilated in the body, keeping us well.

Question 2.
Plant breeding
Answer:
Plant breeding is the improvement or purposeful manipulation in the heredity of crops and the production of new superior varieties of existing crop plants.

Question 3.
Germplasm collection
Answer:
Germplasm collection is the entire collection having all the diverse alleles for all genes in a given crop.

Question 4.
Mutation
Answer:
Mutation is defined as the sudden heritable change in the genotype, which is caused naturally.

Question 5.
Tissue culture
Answer:
Tissue culture is growing isolated cells, tissues, organs ‘in vitro’ on a solid or liquid nutrient medium, under aseptic and controlled conditions of light, humidity and temperature, for achieving various objectives.

Question 6.
Explant
Answer:
The part of plant used in tissue culture is known as explant.

Question 7.
Totipotency
Answer:
An inherent ability of living plant cell to grow, divide, redivide and give rise to a whole plant is known as totipotency.

Question 8.
Callus
Answer:
Callus is defined as a mass of undifferentiated cells, formed by division and redivision of the cells of explant.

Question 9.
Single cell protein
Answer:
Single cell protein is defined as a crude or a refined edible protein, extracted from pure microbial cultures or from dead or dried cell biomass.

Question 10.
Biofortiflcation
Answer:
Biofortification is a method of developing crops having higher quantity and quality of vitamins, minerals and fats, to overcome problem of malnutrition.

Question 11.
Animal husbandry
Answer:
Animal husbandry is an agricultural practice of breeding and raising livestock.

Question 12.
Inbreeding
Answer:
Breeding of closely related individuals for 4 to 6 generations is known as inbreeding.

Question 13.
Outbreeding
Answer:
Breeding of unrelated animals either of the same breed but having no common ancestors for 4 to 6 generations (outcrossing) or of different breeds (crossbreeding) or even of different species (interspecific hybridization), is known as outbreeding.

Question 14.
Outcrossing
Answer:
Breeding of animals of the same breed but having no common ancestors for 4 to 6 generations is known as outcrossing.

Question 15.
Crossbreeding
Answer:
Breeding of superior male of one breed with superior female of another breed is known as crossbreeding.

Question 16.
Interspecific hybridization
Answer:
Breeding of animals of two different but related species is known as interspecific hybridization.

Question 17.
Apiculture
Answer:
Apiculture is an artificial rearing of honey bees to obtain bee products like honey, wax, pollens, bee venom, propolis (bee glue) and royal jelly and to use honey bees as pollinating agents for crop plants.

Question 18.
Antibiotics
Answer:
Antibiotics are organic substances produced in small amounts by certain microbes to kill or inhibit the growth of other microbes.

Question 19.
Biotechnology
Answer:
Biotechnology is defined as the applications of scientific and engineering principles for the processing of materials by biological agents to provide goods and service to humans or for human welfare.

Question 20.
Biocontrol or biological control:
Answer:
Biocontrol is the natural method of eliminating and controlling insects, pests and other disease-causing agents by using their natural, biological enemies.

Question 21.
Biocontrol agents
Answer:
Biocontrol agents are the organisms like insects, bacteria, fungi, viruses and protozoans which are employed for biocontrol.

Question 22.
Fertilizers
Answer:
Fertilizers Eire the nutrients necessary for plant growth and which increase the productivity of cultivated plants.

Question 23.
Biofertilizers
Answer:
Biofertilizers are commercial preparation of ready-to-use live bacterial, cyanobacterial (mostly N₂ fixing) or fungal formulations which enhance the nutrient quality of soil.

Name the Following

Question 1.
Hybrid wheat varieties in India.
Answer:
Sonalika and Kalyan Sona

Question 2.
Semi-dwarf rice varieties in India.
Answer:
Jaya, Padma and Ratna

Question 3.
Sugar cane varieties developed at Coimbatore, Tamil Nadu.
Answer:
CO-419, 421, 453

Question 4.
Hybrid varieties of millets developed in India.
Answer:
Ganga-3 (maize), CO-12 (Jowar), Niphad (Bajra)

Question 5.
Fungal disease of plants.
Answer:
Brown rust of wheat, Red rot of sugar cane, Late blight of potato

Question 6.
Bacterial disease of plants.
Answer:
Black rot of crucifers

Question 7.
Viral disease of plants.
Answer:
Tobacco mosaic disease

Question 8.
Mutant variety of rice.
Answer:
Jagannath

Question 9.
Mutant variety of wheat.
Answer:
NP 836 (rust resistant)

Question 10.
Mutant variety of cotton.
Answer:
Indore-2 (resistant to bollworm)

Question 11.
Mutant variety of cabbage.
Answer:
Regina-II

Question 12.
The most preferred tissue culture medium.
Answer:
MS (Murashige and Skoog) medium.

Question 13.
High yielding varieties of banana used in Maharashtra.
Answer:
Shrimati, Basarai, G-9

Question 14.
The fungi used for the production of SCP.
Answer:
Aspergillus niger, Trichoderma viride, Saccharomyces cerevisiae, Candida utilis.

Question 15.
Algae used for the production of SCR
Answer:
Spirulina spp, Chlorella pyrenoidosa

Question 16.
Bacteria used for the production of SCR
Answer:
Methylophilus methylotrophus, Bacillus megasterium

Question 17.
A new breed of sheep developed from crossing of Bikaneri ewe and Marino rams in Punjab.
Answer:
Hisardale

Question 18.
Indian breeds of cows.
Answer:
Sahiwal, Sindhi, Gir

Question 19.
Exotic breeds of cows.
Answer:
Jersey, Brown Swiss, Holstein

Question 20.
Breeds of bufaaloes in India.
Answer:
Jaffarabadi, Mehsana, Murrah, Nagpuri, Nili, Surati.

Question 21.
Common breeds of cattle and poultry in the farms, found in your area.
Answer:
Khillari, Gir (breeds of cows), Aseel, Kadaknath (poultry)

Question 22.
American poultry breeds.
Answer:
Plymouth Rock, New Hampshire, Rhode Island Red

Question 23.
Asiatic poultry breeds.
Answer:
Brahma, Cochin and Langshan

Question 24.
Mediterranean poultry breeds.
Answer:
Leghorn, Minorca

Question 25.
English poultry breed.
Answer:
Australorp

Question 26.
Indian poultry breeds.
Answer:
Chittagong, Aseel, Brahma and Kadaknath.

Question 27.
Best layer.
Answer:
Leghorn

Question 28.
Best broilers.
Answer:
Plymouth rock, Rhode Island Red, Aseel, Brahma and Kadaknath

Question 29.
Viral diseases of poultry.
Answer:
Ranikhet, Bronchitis, Avian influenza (bird flu), Bird flu

Question 30.
Bacterial diseases of poultry.
Answer:
Pullorum, Cholera, Typhoid, TB, CRD (chronic respiratory disease), Enteritis.

Question 31.
Fungal diseases of poultry.
Answer:
Aspergillosis, Favus and Thrush.

Question 32.
Parasitic diseases of poultry.
Answer:
Lice infection, roundworm, caecal worm infections, etc.

Question 33.
Protozoan diseases of poultry.
Answer:
Coccidiosis

Question 34.
Domesticated species of bees.
Answer:
Apis mellifera, Apis indica

Question 35.
Lac insect.
Answer:
Trachardia lacca

Question 36.
Silk moth.
Answer:
Bombyx mori

Question 37.
The common fresh water fish.
Answer:
Labeo rohita (rohu), Catla (catla), Cirrihanus mrigala (mrigala) and other carps.

Question 38.
The common marine fish.
Answer:
Harpadon (Bombay duck), Sardinella (sardine), Rastrelliger (mackerel) and Stromateus (pomphret).

Question 39.
Estuaries found in Maharashtra and where these estuaries are located.
Answer:
Thane creek, Manori creek, Rajapuri creek, Kalbadevi Estuary in Ratnagiri, Damanganga estuary and Narmada estuary

Question 40.
Different fish found at an estuary.
Answer:
Clupeids, mullets, catfishes, perches, Mugil cephalus gar fishes, halfbeaks, eels, flatfishes, sharks, rays, oysters and migratory fishes include Hilsa ilisha, Polynemus spp., Pampana, Tachysurus spp, Pangasius spp., etc.

Question 41.
Best Silk.
Answer:
Mulberry silk

Question 42.
Silk of inferior quality.
Answer:
Tussar silk, Eri silk

Question 43.
Distilled alcoholic beverages.
Answer:
Whisky, brandy, rum

Question 44.
Traditional drink made by fermenting the sugar sap extracted from palm plants and coconut palm.
Answer:
Toddy

Question 45.
The wine of Goa, made by fermenting fleshy pedicels of cashew fruits.
Answer:
Fenny

Question 46.
The microbes used in fermentation of dhokla.
Answer:
Lactobacilli

Question 47.
Microbes used in the production of vitamin B₂.
Answer:
Neurospora gossypii, Eremothecium ashbyi

Question 48.
Microbes used in the production of vitamin B₁₂.
Answer:
Pseudomonas denitrtficans

Question 49.
Microbes used in the production of vitamin C.
Answer:
Aspergillus niger

Question 50.
Symbiotic N₂ fixing microorganisms.
Answer:
Rhizobium, Anabaena, Frankia.

Question 51.
Free-living or Non-Symbiotic N₂ fixing microorganisms.
Answer:
Azotobacter, Nostoc, Clostridium, Beijerinkia, Klebsiella, etc.

Question 52.
Phosphate solubilizing biofertilizers.
Answer:
Pseudomonas striata, Bacillus polymyxa, Agrobacterium, Microccocus, Aspergillus spp., etc.

Question 53.
Nitrogen fixing cyanobacteria.
Answer:
Anabaena, Nostoc, Plectonema, Oscillatoria.

Question 54.
Cyanobacteria associated with lichens.
Answer:
Anabaena, Nostoc and Tolypothrix

Question 55.
Cyanobacteria associated with plants like Azolla and Cycas.
Answer:
Anabaena

Question 56.
The aquatic fern commonly used in paddy field as a biofertilizer.
Answer:
Azolla.
Give functions or significance

Question 1.
Hybridization
Answer:

1. Hybrdization is an effective means of combining together the desirable characters of two or more varieties.
2. New genetic combinations of already existing characters and new genetic variations can be created by hybridization.
3. Hybridization exploits and utilizes hybrid- vigour.

Question 2.
Food
Answer:

1. Food is organic, energy rich, non-poisonous, edible and nourishing substance.
2. It provides nutrients for growth and development of body.
3. It provides energy for metabolic reactions.
4. It keeps us alive, strong and healthy.

Question 3.
Antibiotics
Answer:

1. Antibiotics are secondary metabolites of therapeutic importance, produced in small amounts by certain microbes like bacteria, fungi and a few algae.
2. They inhibit growth of other microbial pathogens like fungi and bacteria.
3. Thus, they are antifungal and antibacterial in nature.
4. Antibiotics are used in treatment of deadly diseases like plague, whooping cough, diphtheria, leprosy, etc.

Distinguish between the following

Question 1.
Callus culture and Suspension culture.
Answer:

Question 2.
Outcrossing and Crossbreeding.
Answer:

Question 3.
Inorganic fertilizers and Organic fertilizers / biofertilizers.
Answer:

Question 4.
Ectomycorrhizae and Endomycorrhizae.
Answer:

Give reasons

Question 1.
Why are honey bees called as best pollinators?
Answer:

1. About 80% of insect pollination is carried by honey bees.
2. They pollinate various crops like sunflower, mustard, safflower, chilly, cabbage, cucumber, legumes, fruits like apple, mango, citrus, etc.
3. They increase the productivity of crops.
4. Hence, honey bees are important pollinators.

Question 2.
Regular visit of veterinary doctor to dairy farm is mandatory.
Answer:
Daily visit of veterinary doctor to dairy farm is mandatory to diagnose health problems, diseases and for their rectification.

Question 3.
Apis mellifera and Apis indica are known as domesticated species.
Answer:

1. Apis mellifera and Apis indica are suitable for apiculture.
2. Hence, they are known as domesticated species.

Question 4.
Cages of silkworm larvae must be well managed and protected.
Answer:

1. Silkworm larvae may get infected by protozoans, viruses and fungi.
2. Ants, crows, other birds and predators may attack these larvae.
3. Hence, cages of silkworm larvae must be well managed and protected.

Question 5.
Buttermilk is used in the dough of dhokla.
Answer:

1. Buttermilk contains the lactobacilli.
2. These lactobacilli bring about the fermentation of gram flour.
3. CO₂ produced during fermentation increases the volume of the dough.
4. It escapes during the steaming of dough, making dhokla porous and spongy.
5. Hence, buttermilk is used in the dough of dhokla.

Question 6.
We include mushrooms in our diet.
Answer:

1. Mushrooms are directly used as food.
2. They produce large, fleshy fruiting bodies which are edible.
3. They are low calorie, sugar free, fat free, but rich in proteins, vitamins, minerals and amino acids.
4. Hence, we include mushrooms in our diet.

Question 7.
Vitamins are to be consumed through food or tablets or capsules.
Answer:

1. Vitamins B and K are produced in the body.
2. But some vitamins like C, D and E are not produced in the body.
3. If our body does not get these vitamins in the required quantity, then the deficiency of these vitamins may result in various diseases.
4. Therefore, vitamins are to be consumed through food or tablets or capsules.

Question 8.
Enzymes are essential for survival of living organisms.
Answer:

1. Enzymes are proteins which act as biocatalysts.
2. They speed up the chemical reactions without undergoing any change themselves.
3. They catalyze reactions more quickly and efficiently at body temperature.
4. Thus they play key role in metabolic reactions.
5. Hence, enzymes are essential for survival of living organisms.

Question 9.
Biogas plants are more often built in rural areas.
Answer:

1. Biogas is a non-conventional and renewable source of energy obtained by microbial fermentation.
2. Cattle dung (the main substrate), domestic wastes, agricultural waste, agro industrial wastes, forestry wastes, etc. are utilized as substrates for production of biogas.
3. Biogas is eco-friendly and does not cause pollution, can be used as domestic fuel.
4. As the raw material for its production is readily available, the biogas plants are more often built in rural areas.

Question 10.
Why are healthy root nodules pink in colour?
Answer:

1. Rhizobium has symbiotic relationship with roots of leguminous plants.
2. It infects root cortex and form root nodules.
3. Root nodules are the site of nitrogen fixation.
4. Enzyme nitrogenase which catalyzes nitrogen fixation, gets inhibited by oxygen.
5. But root nodule contain a pigment called leghaemoglobin which acts as oxygen scavanger and protects nitrogenase from getting inhibited.
6. Leghaemoglobin is pink in colour.
7. Hence, healthy root nodules are pink in colour.

Give Short Notes

Question 1.
Callus culture.
Answer:

1. In callus culture, nutrient medium is solidified using agar-agar is used.
2. Shaker or agitator is not required.
3. Sterilized explant is placed on solid nutritive medium.
4. The cells of explants absorb nutrients and start multiplying.
5. This results in the formation of callus.
6. Callus is a mass of undifferentiated cells, formed by division of the cells of explants.
7. Growth hormones, auxins and cytokinins are provided to callus in specific proportion to induce formation of organs.
8. If auxins are in more quantity, roots are formed (rhizogenesis) and if the cytokinins are in more quantity, shoot formation takes place (caulogenesis).
9. Thus new plantlets are formed.
10. Callus culture required subculturing to ensure its continuous growth.

Question 2.
Suspension culture.
Answer:

1. In suspension culture, small groups of cells or a single cell are transferred to liquid nutritive medium as explants.
2. The liquid medium is constantly agitated by using shakers (agitators).
3. The agitation serves the purpose of aeration, mixing of medium and prevents the aggregation of cells.
4. Generally the suspension culture shows a high proportion of single isolated cells and small clumps of cells.
5. Suspension culture grows much faster than callus culture.
6. Suspension culture is used for cell biomass production which can be utilized for biochemical isolation, regeneration of new plants, etc.

Question 3.
Applications of micropropagation.
Answer:

1. Micropropagation involves in rapid multiplication of genetically similar plants (clones).
2. A large number of plantlets are obtained within a short period and in a small space.
3. Plants are obtained throughout the year, under controlled conditions, independent of seasons.
4. As micropropagation results in the formation of clones, desirable characters (genotype and sex) of superior variety can be maintained for many generations.
5. The rare plant and endangered species are multiplied and conserved using this technique.
6. With the help of somatic hybrids (cybrids), new variety can be obtained in short time span.
7. Micropropagation is involved in commercial production of ornamental plants like v orchids, Chrysanthemum, Eucalyptus, etc. and fruit plants like banana, grapes, Citrus, etc.

Question 4.
Applications of tissue culture.
Answer:
Applications of tissue culture are as follows:

1. Production of healthy plants from diseased plants using apical meristems as explants.
2. Production of stress resistant plants.
3. Production of haploid plantlets by pollen culture.
4. Production of secondary metabolites such as alkaloids, enzymes, hormones, etc.
5. Multiplication of rare and endangered plants.
6. Production of somaclonal variants.
7. Use of micropropagation techniques to produce large number of genetically identical plants.
8. Protoplast culture
9. Tissue culture has applications in forestry, agriculture, horticulture, genetic engineering and physiology.

Question 5.
Single cell protein (SCP).
Answer:

1. Single-cell protein is a crude or a refined edible protein, extracted from pure microbial cultures or from dead or dried cell biomass.
2. Microorganisms like algae, fungi, yeast and bacteria with high protein content in their biomass, are grown using waste and inexpensive substrates.
3. Substrates used for growing microbial biomass are wood shavings, sawdust, corn cobs, paraffin, N-alkanes, sugar cane molasses, even human and animal wastes.
4. SCP is rich in proteins, vitamins, vitamin B complex, minerals and fats.
5. It can be used as fodder for achieving fattening of calves, pigs, in breeding fish and even in poultry and cattle farmimg.
6. Fungi like Aspergillus niger, Trichoderma viride, Saccharomyces cerevisiae, Candida utilis, algae like Spirulina spp, Chlorella pyrenoidosa, bacteria like Methylophilus, methylotrophus and Bacillus megasterium are used for the production of SCR

Question 6.
Advantages of Single Cell Protein.
Answer:

1. Microbes that are used as SCP have very high protein contents in their biomass – 43% to 85% (W/W basis).
2. SCP is a good source of vitamins, vitamin B complex, fats, amino acids, minerals, crude fibres, etc.
3. As microorganisms multiply fast, large quantity of biomass can be produced in a short duration.
4. The microbes can be grown using waste materials and inexpensive substrates. This decreases pollution.
5. The microbes can be genetically modified to vary the amino acid composition.
6. SCPs can be used as fodder for achieving fattening of calves, pigs, in breeding fish, poultry and cattle farming.

Question 7.
Inbreeding.
Answer:

1. Inbreeding is the mating of two closely related individuals of the same breed for 4 to 6 generations.
2. During inbreeding superior males and superior females of the same breed are identified. The superior males and superior females from this progeny are identified and used for further mating.
3. Due to inbreeding, homozygosity is increased and harmful recessive genes are exposed. Inbreeding is done when a pure line of an animal is expected.
4. Inbreeding helps in accumulation of superior genes and elimination of harmful or less desirable genes.
5. Continued inbreeding usually reduces fertility and productivity. This is called inbreeding depression.

Question 8.
Fish farming.
Answer:
Fish farming is the practice of culturing the edible and commercially important fish species in the ponds, lakes or reservoirs. Fish farming helps in boosting the productivity and the economy of the nation.

For maintaining a fish farm, following aspects are taken into consideration:

• selection of the site
• excavation of the pond
• managing hatchery
• nursery
• looking after rearing ponds and
• stocking ponds besides managing the water source, supplying fertilizer and supplementary feed, etc.

Question 9.
Microbes in industrial vitamin production.
Answer:
(1) Vitamins are nitrogenous organic compounds, required in minute quantities for normal growth and development of the body.

(2) The microbes are involved in the industrial production of vitamins like thiamine (vitamin B₁, riboflavin (vitamin B₂), pyridoxine, folic acid, pantothenic acid, biotin, vitamin B₁₂, ascorbic acid (Vitamin C), beta-carotene (provitamin A) and ergosterol (provitamin D).

(3) Examples of some vitamins produced by fermetaion using different microbial sources are-

• Vitamin B₂ – Neurospora gossypii, Eremothecium ashbyi
• Vitamin B₁₂ – Pseudomonas denitrijicans
• Vitamin C – Aspergillus niger

Question 10.
Industrial uses of enzymes.
Answer:

1. Enzymes are used to improve the quality of the fabrics in the textile industry.
2. In the pulp and paper industry, they are involved in biomechanical pulping and bleaching.
3. In food industry, enzymes are used in the fermentation processes to produce bread and alcoholic beverages such as wine and beer.
4. They are used in the extraction of carotenoids and olive oil.
5. Enzymes are also used in cosmetics, animal feed and agricultural industries.
6. Lipases are used to remove oil stains and to increase the brightness in detergent industry. They have superior cleaning properties.
7. Streptokinase is used as a ‘clot buster’ for clearing blood clots in the blood vessels in heart patients.

Question 11.
Microorganisms in sewage.
Answer:

1. Sewage contains pathogenic bacteria, viruses, fungi, protozoa which cause dysentery, cholera, typhoid, polio and infectious hepatitis, etc. It also contains nematodes and algae.
2. Their number and type of microorganisms in sewage depends on the composition and source of sewage.
3. Millions of bacteria per ml may be present in raw untreated sewage.
4. Bacteria in sewage include coliforms, fecal Streptococci, anaerobic spore forming bacilli and other bacteria found in the intestinal tract of humans.
5. The sewage also contains soil bacteria.
6. During sewage decomposition, initially aerobic and facultative anaerobic organisms predominate which are followed by strict anaerobic especially methogenic bacteria that produce methane (CH₄) and CO₂.

Question 12.
Rhizobia as a biofertilizer
Answer:

1. Rhizobia [Singular – Rhizobium) are rod¬shaped, motile, aerobic, gram negative, non- spore forming, nitrogen-fixing bacteria.
2. They contain Nod genes and Nif genes.
3. They live in symbiotic association with leguminous roots.
4. They form nodule on the roots of leguminous plants and multiply inside the nodule.
5. Nodules are the site of nitrogen fixation. They are pink in colour and contain enzyme nitrogenase and oxygen scavenger leghaemoglobin.
6. Rhizobia fix atmospheric nitrogen into organic forms, which can be used by plants as nutrients. The host plant in return provides food and water to the bacterium (Rhizobia).
7. Rhizobia are host specific e.g. leguminosarum is specific to pea R. phaseoli is specific to beans.
8. In a laboratory, pure cultures of specific Rhizobium species are raised which are used for the preparation of biofertilizer.

Question 13.
Azotobacter as a biofertilizer
Answer:

1. Azotobacter is a free living, nitrogen fixing, aerobic, non-photosynthetic, non-nodule forming bacterium.
2. It is associated with roots of grasses and certain plants.
3. It is used as a biofertilizer for non-leguminous plants like rice, cotton, vegetables, etc.

Question 14.
Azospirillumas as a biofertilizer
Answer:

1. Azospirillum acts as a biofertilizer for non- leguminous plants like cereals, millets, cotton, oilseed, etc.
2. It is a free living, aerobic nitrogen fixing bacterium associated with roots of corn, wheat and jo war.
3. It fixes the nitrogen (20-40 kg N/ha).

Question 15.
Anabaena as a biofertilizer
Answer:

1. Anabaena is a cyanobacterial biofertilizer.
2. It is multicellular, filamentous nitrogen fixing organism that exits as plankton.
3. It can fix nitrogen both in free living conditions as well as by forming symbiotic associations.
4. Anabaena forms symbiotic relationship with Azolla, Anthoceros and Cycas.
5. It is found in dorsal leaf lobe in Azolla, thallus of Anthoceros and in coralloid roots of Cycas.
6. It has specialized colourless cells known as heterocysts.
7. Heterocysts are the sites for nitrogen fixation.

Question 16.
Benefits of Biofertilizers.
Answer:

1. Biofertilizers increase soil fertility.
2. They are low cost and can be used by marginal farmers.
3. They do not cause pollution.
4. BGA secret growth promoting substances, organic acids, proteins and vitamins.
5. Azotobacter supplies nitrogen and antibiotics in the soil.
6. Use of biofertilizers improves physico-chemical properties of soil-like texture, structure, pH, water holding capacity of soil by providing nutrients and organic matter.
7. The use of chemical fertilizers gets reduced and the pollution also becomes less.

Short Answer Questions

Question 1.
What are the objectives of plant breeding?
Answer:
Objectives of plant breeding are as follows:

1. To increase crop yield,
2. To improve quality of produce.
3. To increase tolerance to environmental stresses.
4. To develop varieties of plants resistant to pathogens and insect pest.
5. To alter the life span.

Question 2.
What are the different types of hybridization in plants?
Answer:
The different types of hybridization in plants are as follows:

1. Intravarietal : It is the hybridization between plants of same variety.
2. Intervarietal : It is the hybridization between two varieties of the same species.
3. Interspecific : It is the hybridization between two species of the same genus.
4. Intergeneric : It is the hybridization between two genera of the same family.
5. Wide/distant crosses : These are the crosses between distantly related parental plants.

Question 3.
How aseptic conditions are maintained in tissue culture?
Answer:

1. Glassware is sterilized by using detergents and hot air oven.
2. Nutrient medium is autoclaved under constant pressure of 15 lb/sq inch, continuously for 20 minutes to sterilize it.
3. Explant is treated with 20% ethyl alcohol and 0.1% HgCl₂.
4. Sterilization of inoculation chamber (Laminar air flow) is done using UV ray tube for 1 hour before actual inoculation of explant on the sterilized nutrient medium.

Question 4.
What are the objectives of biofortification ?
Answer:
Objectives of biofortification are as follows:

1. Improvement in protein content and quality.
2. Improvement in oil content and quality.
3. Improvement in vitamin content.
4. Improvement in micronutrient content and quality.
5. To overcome the problem of malnutrition.

Question 5.
What are the objectives of animal breeding?
Answer:
Objectives of animal breeding are as follows:

1. To increase the yield of animals.
2. To improve the production of milk, quality of milk product, quality of meat or maximum yield of eggs per year, etc.
3. To develop breeds with desirable characters.

Question 6.
What is artificial insemination? What are its advantages?
Answer:

1. Artificial insemination is the technique used for controlled breeding experiments.
2. Superior males of a particular commercial breed are selected.
3. Semen from such superior males is collected and injected into the genital tract of female.
4. This insemination is either done immediately or semen is frozen and used later on.
5. In frozen semen, sperms can remain alive for long duration. They are also convenient for transport.
6. Artificial insemination is preferred as it is easy and helpful to overcome several problems of normal mating.

Question 7.
What is Multiple Ovulation Embryo Transfer (MOET) technology? Where is it used?
OR
Explain the technique of multiple ovulation embryo transfer (MOET) in animal breeding.
Answer:

1. Multiple Ovulation Embryo Transfer (MOET) technology is used to increase chances of successful production of hybrids.
2. In this technique, cow is administered with Follicle Stimulating Hormone (FSH) which induces follicular maturation and then the super ovulation is brought about.
3. By such technique in each cycle, 6 to 8 eggs mature simultaneously.
4. The cow is then either mated with a superior bull or she is artificially inseminated.
5. The blastocysts at 8 to 32 cell stage are recovered non-surgically and transferred to surrogate mothers.
6. The genetic mother who gave the egg is then again subjected to another round of super ovulation.
7. This technology is used for cattle, sheep, rabbits, buffaloes, etc.
8. The MOET is used to produce high milk yielding breeds of female and high quality meat yielding bulls with lean meat containing less lipids. It helps in increasing favourable herd size in a short period.

Question 8.
As a dairy owner what measures will you adopt to improve the quality of milk?
Answer:

1. In order to improve the quality of milk, following measures should be taken at every stage of dairy farming:
2. Good breeds having high yielding potential should be selected.
3. The breeds selected should be suitable for the local climatic conditions.
4. The breeds selected should have proper resistance to diseases.
5. Cattles should be well looked after with proper care.
6. The feed should be of suitable quality and quantity. Feed includes silage made from legumes, grasses, maize and jowar. Silage should be supplemented with oilcakes, minerals, vitamins and salts.
7. Utmost care should be taken about cleanliness and hygiene of the cattle as well as the handlers who handle the cattle.
8. This is especially important during milking, storage and transport of milk and its products. Mechanized processes should be adopted as far as possible as they reduce chance of direct contact of produce with the handlers.
9. The shed must be clean and well maintained. Similarly the dairy should be spacious with adequate facilities for feeding, watering and light.
10. Help of veterinary doctor should be sought from time to time for the identification of health problems, diseases and rectification.
11. Transportation of milk, processing, marketing and distribution play a vital role in dairy industry. If all the above care is taken then the quality of milk will surely improve.

Question 9.
Explain in short the poultry management.
Answer:
For the management of poultry, following aspects are to be taken care of:

1. Selection of proper and disease free breed, suitable and safe farm conditions.
2. Proper feeding practice and the quality of feed and water.
3. Hygiene and health care of the birds.
4. Management of layers is done by selecting high yielding chicken. Their farms are kept clean, dry and well ventilated. They are given proper feed at proper times. Other aspects such as debeaking, etc. are also taken care of.
5. In the farm, importance is given to infrastructure such as proper and adequate lighting, placing waterer at places, looking after sanitation, culling and vaccination.
6. Management of broiler similarly includes selection of breed, housing, temperature, ventilation, lighting, observing the floor space and broiler feed.

Question 10.
What is apiculture? What is its importance?
Answer:

1. Apiculture is artificial rearing of honey bees to obtain various bee products.
2. Various products such as honey, wax, pollen, bee venom, propolis (bee glue) royal jelly, etc. are obtained from this cottage industry. Honey is an important item as ayurvedic medicine and in food due to its nutritional value.
3. Bees also help in the cross pollination of various crops. Hence in pastures, wild shrubs, fruit orchards and cultivated crops, honeybees play an important role as pollinators.
4. Bee keeping in crop fields increases the productivity of both honey and the crop.
5. Apiculture itself is a means for employment for rural youth. It is an age old cottage industry which can be done along with agriculture.

Question 11.
What are the requirements of bee keeping?
Answer:

1. Bee keeping requires bee hive boxes which consist of comb foundation sheets.
2. In addition, the bee veil, smoker, bee brush, gloves, gumshoes, uncapping knives, swarm net, queen excluder, overall hive tool, etc. are required.
3. Bee keeping requires familiarity with the habits of bees, selection of suitable location, catching and hiving of swarms, management of hives during different seasons, handling and collection of honey, bee wax and other products.
4. Successful bee keeping also requires periodic inspection for cleanliness of hive boxes, activity of bees and queen, condition of brood, provision of water.

Question 12.
What are the main divisions of fishery?
Answer:

1. Fishery can be capture fishery and culture fishery.
2. Three main divisions of capture fishery are : Inland fishery, estuarine fishery and marine fishery.
3. Inland fishery : It is culturing and capturing of from fresh water bodies. It is carried out on about 40 to 50 lakh acres of fresh water bodies such as rivers, ponds, lakes and dams.
4. Marine fishery : It includes capturing fish from sea water. India has a coastline of about 7500 km.
   Estuarine fishery : It includes capture of fish from estuaries.
5. Culture fishery is either of polyculture or of monoculture type. In polyculture, different species are cultured simultaneously at the same time in the same pond. In monoculture, only a single species is cultured.

Question 13.
Can “fishery” be a sustainable job option?
Answer:

1. Fishery can never be a job. It is a livelihood or can be an occupation.
2. Fish is a renewable resource. If managed properly, it can be a sustainable resource.
3. The sustainability is dependent upon the availability of fishes and other edible organisms. But due to climate change, pollution and overexploitation of fish resources, these are depleting rapidly, it is estimated by the scientists that by 2050, no fish will be left in the seas.
4. However, if aquaculture is done to raise fishes, partly it can be sustaining. But there . are many environmental regulations that can hamper the business of aquaculture.

Question 14.
Describe sericulture in brief.
Answer:

1. Sericulture is the practice of rearing silkworms for the production of silk.
2. The silkworm (Bombyx mort) is reared for obtaining best quality of silk called mulberry silk. Tussar silk and Eri silk are other varieties of silk which are inferior to the mulberry silk.
3. Larvae of silkworm are fed on the mulberry leaves. Quality and quantity of silk depends on the quality of mulberry leaves.
4. These larvae are reared, developed and well looked after by the skilful labour keeping a constant watch.
5. Silkworm larvae may be infected by protozoans, viruses and fungi. Ants, crows, birds, and other predators are ready to attack these insects, hence the cages of these larvae must be managed to prevent predators attack.
6. Silk is obtained from the cocoon of the silkworm.
7. Sericulture is an age old practice and can be started with low investment and small space. It requires scientific knowledge and skill. Disabled, older and handicapped people also can practise it.

Question 15.
What are the different stages found in the life cycle of silkworm?
Answer:

1. Stages of development in the life cycle of silkworm are egg, larva, pupa and adult.
2. The larva is the silkworm caterpillar.
3. The adult (imago) stage is the silkworm moth.

Question 16.
Describe the process of cocoon formation.
Answer:

1. The eggs of silkworm hatch into larvae.
2. The larvae develop into a caterpillar.
3. Caterpillar feeds on fresh mulberry leaves.
4. After its growth and moulting, the silkworm secretes a silk fibre to form cocoon.
5. The silk is a continuous filament comprising fibroin protein, secreted from salivary glands of silkworm and a gum called sericin, which cements the filaments.
6. The silk solidifies when it contacts the air.
7. The silkworm spins approximately one mile of filament and completely encloses itself in a cocoon in about two or three days.

Question 17.
Which process is involved in silk production from cocoon?
Answer:

1. The silk is a continuous filament comprising fibroin protein, secreted from salivary glands of silkworm and a gum ailed sericin.
2. To remove the sericin, which cements,the filaments, cocoons are placed in hot water.
3. It frees the silk filaments and readies them for reeling. This is known as the degumming process.
4. The sillworm pupa gets killed in hot water.
5. Single filaments are combined to form thread.
6. The threads are plied to form yarn.
7. After drying, the raw silk is packed according to quality.

Question 18.
Give the economic importance of lac.
OR
State the economic importance of ‘lac culture’.
Answer:
Lac is used for the following purposes:

1. For making bangles.
2. For making different types of toys.
3. It is used in wood works.
4. Polish is made from lac.
5. Inks can be prepared from lac.
6. Lac is largely used for silvering mirrors.

Question 19.
Tribal people from India have a great contribution in production of lac. But it needs certain trees. Name at least two such trees which give food yield of lac. How is lac purified?
Answer:

1. Like her, peepal, palas, kusum, babul, etc. are used for feeding lac insects during the practice of lac culture.
2. Natural lac is contaminated and hence it is washed and purified. This helps to obtain shellac in pure form.

Question 20.
Give an account of alcoholic beverages.
Answer:

1. Alcoholic beverages are the products of alcoholic fermentation of particular substrates.
2. Tubular tower fermenters are used to produce alcoholic beverages on a large scale.
3. Beer is produced from barley by fermentation. For the production of beer, strains of Saccharomyces cerevisiae are used.
4. Wine is prepared from grapes.
5. Whisky is prepared by fermenting mixed grains of wheat, barley and corn followed by the distillation of the products of fermentation.
6. Liquors like beer, wine are produced without distillation.
7. Whisky, rum and brandy are distilled alcoholic beverages.
8. Toddy is prepared by fermenting the sugar sap extracted from palms and coconut palms.
9. Fenny is fermented by fleshy pedicels of cashew fruits.

Question 21.
Industrial production of which substances involves fermentation by microbes? What is the nature of these substances and which factors determine the synthesis of specific products?
Answer:

1. During fermentation of substrates, various useful products like alcoholic beverages, organic acids, vitamins, growth hormones, enzymes, antibiotics and other molecules of medical significance are produced.
2. They are secondary metabolites produced during idio phase and are not required for their growth.
3. A specific secondary metabolite is produced depending on the type of microorganism and the type of substrate.

Question 22.
Can antibiotics kill viruses?
Answer:

1. Antibiotics work by targeting cell wall or other metabolic pathways in bacteria.
2. But viruses do not have cell walls and they do not carry out any metabolic reaction when outside the host.
3. Hence, antibiotics cannot kill viruses.

Question 23.
What are gibberellins? Give the applications of gibberellins.
Answer:
Gibberellins are growth hormones produced by higher plants and fungi.

Applications of gibberellins are as follows:

1. Gibberellins induce parthenocarpy in fruits like pear and apple.
2. Gibberellins promote growth by stem elongation.
3. They break the dormancy of seeds.
4. They induce flowering in long day plants in short day conditions.
5. They are used to enlarge the size of grapes.

Question 24.
What is sewage? Describe its composition.
Answer:

1. Sewage is the waste matter carried off on drainage.
2. Composition of sewage varies depending upon its industrial source, e.g. textile, chemicals, pharmaceuticals, dairy, canning, brewing, meat packing, tannery, oil refineries and meat industries, etc.
3. Sewage consists of human excreta, animal dung, household waste, slaughter house waste, dissolved organic matter, algae, nematodes, pathogenic bacteria, viruses and protozoa, discharged waste water from hospitals, industries (contains toxic dissolved organic and inorganic chemicals), tannery and pharmaceutical waste, etc.
4. Bacteria in sewage include coliforms, fecal Streptococci, anaerobic spore forming bacilli and other bacteria found in human intestinal tract.
5. Sewage consists of about water (99.5% to 99.9%) and inorganic and organic matter (0.1 to 0.5%) in suspended and soluble form.

Question 25.
State whether BOD will be high or low
(a) in water after primary treatment
(b) in water after secondary treatment.
Answer:
(a) After primary treatment, the primary effluent present in the primary sedimentation tank, still contains large amount of dissolved organic matter. Hence, the BOD is high.

(b) Secondary treatment is a biological treatment. Primary effluent is passed into aeration tank, where aerobic bacteria and fungi form flocks and consume the major part of organic matter in the effluents. Hence, the BOD is reduced.

Question 26.
Enlist the advantages of biogas.
Answer:
Advantages of biogas are as follows:

1. Biogas is a cheap, safe, non-conventional and renewable source of energy.
2. It can be easily generated, stored and transported.
3. Biogas burns with a blue flame without producing smoke.
4. Biogas is of great help in improving ‘ the sanitation of the surrounding.
5. Biogas is an eco-friendly gas. It does not cause pollution and imbalance of the environment.
6. Leftover sludge can be used as fertilizer.
7. It is used as domestic and industrial fuel. Biogas can be used for domestic lighting, street lighting, cooking, small scale industries, etc.

Question 27.
Explain how Bacillus thuringiensis acts as a bio-control agent.
Answer:

1. Bacillus thuringiensis (Bt) is an effective biocontrol agent against butterfly, caterpillars.
2. Dried spores of Bacillus thuringiensis are mixed with water and sprayed onto vulnerable plants such as Brassicas and fruit trees.
3. When insect larvae eat the leaves, they get killed by the toxin (cry protein) released in their gut by bacteria.

Question 28.
Explain how Trichoderma acts as a bio-control agent.
Answer:

1. Trichoderma is an effective biocontrol agent against soil borne fungal plant pathogens.
2. It is a free-living fungus found in the root ecosystem (rhizosphere).
3. It produces substances like viridin, gliotoxin, gliovirin, etc. that inhibit the soil borne pathogens which infect root and rhizomes to cause rot disease.

Question 29.
What are bioherbicides? Give any two examples.
Answer:

1. Bacteria, fungi and insects which kill the dicot herbs which acts as weeds in the fields of monocot cereal crops, are known as bioherbicides.
2. Pseudomonas spp. and Xanthomonas spp. kill several weeds.
3. Fungus Alternaria crassa controls water hyacinth.

Question 30.
What is composting? Which microorganisms are found in active compost?
Answer:

1. Composting is a natural process in which organic matter is converted into a dark rich compost or humus.
2. During composting, microorganisms break down organic matter into compost.
3. Microorganisms found in active compost are bacteria, fungi, actinobacteria, protozoa and rotifers.

Question 31.
What are cyanobacteria? Give any two examples cyanobacteria as biofertilizers.
Answer:

1. Cyanobacteria are aerobic, photosynthetic, N₂ fixing microorganisms.
2. They are aquatic or terrestrial.
3. They may be free-living or symbiotic.
4. They may be heterocystous or non- heterocystous. Heterocyst is the site of nitrogen fixation.
5. e.g. Free living cyanobacteria are Anabaena, Nostoc, Tolypothrix, Plectonema, Oscillatoria.
6. Anabaena and Nostoc have symbiotic relationship with lichens.
7. Anabaena is also symbiotically associated with Azolla and Cycas.

Chart based or table based questions

Question 1.
Complete the table given below.

Answer:

Question 2.
Complete the table given below.

Answer:

Diagram based questions

Question 1.
a. Identify A and B in the following diagram.
b. What is organogenesis?
c. What is meant by hardening?

a. A : Explant, B : Callus

b. When auxins are provided to callus in more quantity compared to cytokinins, it gives rise to roots (rhizogenesis) and when cytokinins are provided in more quantity, there is development of shoot (caulogenesis). This induction of organ formation in callus by providing growth hormones in proper proportion is known as organogenesis.

c. Plantlets produced in tissue culture laboratory are transferred to polythene bags containing sterilized soil and are kept on low light and high humidity conditions for suitable period of time. This is known as hardening.

Question 2.
a. Identify honey bees A, B and C in the given diagram.
b. They belong to which species?

a. A : Worker honey bee, B : Queen honey bee, C : Drone of honey bee
b. They belong to species Apis mellifera.

Question 3.
Identify A, B, C and D in the given diagram.

Answer:
A : Honey super
B : Queen excluder
C : Hive bodies
D : Entrance reducer

Question 4.
Identify fish A, B, C and D in the given diagram.

Answer:
A : Rohu fish,
B : Mrigal fish,
C : Grass carp and
D : Silver carp

Question 5.
a. Identify A, B and C in the given diagram.
b. The given diagram represent life cycle of _____

a. A : Mature caterpillar, B : Cocoon and C : Adult female
b. Silk moth (Bombyx mori)

Question 6.
a. Identify stages A and B in the given diagram.
b. Larvae are also called …………..
c. The diagram represent life cycle of ……………

Answer:
a. A : Hatching, B : Pupa
b. Crawlers
c. Lac insect

Question 7.
Draw a labelled diagram of Tubular tower fermenter.
Answer:

Question 8.
Draw a labelled diagram of biogas plant.
Answer:

Question 9.
a. Identify A in the given diagram.
b. Name the bacteria which form ‘A’ in roots of leguminous plants.

Answer:
a. A : Root nodules
b. Rhizobia form root nodules in leguminous plants.

Question 10.
Draw a labelled diagram of T.S. of root nodule.
Answer:

Question 11.
Identify and describe the plant in the given diagram.

Answer:
The plant in the given diagram is Azolla.
Azolla is an aquatic fern that has symbiotic association with nitrogen fixing cyanobacterium Anabaena.
It propagates vegetatively and spreads in rice fields very rapidly.
It has a floating rhizome with small overlapping bilobed leaves and roots.
Azolla provides habitat to Anabaena.
The leaf shows dorsal and ventral lobe.
7. Anabaena filaments are present in the aerenchyma of dorsal lobe.

Question 12.
a. Identify A, B and C in the given diagram.
b. Name the plant which has symbiotic relationship with ‘A’.

Answer:
a. A : Anabaena, B : Photosynthetic zone. C : Dorsal lobe.
b. Azolla m

Long Answer Questions

Question 1.
Explain concept of outbreeding and its types.
Answer:
(1) Outbreeding involves breeding of two unrelated animals.
(2) It is of three types, viz. outcrossing, cross-breeding and interspecific hybridization.

(3) Outcrossing:

• Outcrossing involves mating of animals of same breed, which do not have a common ancestors on either side of mating partners up to 4 to 6 generations.
• The progeny obtained from such mating is called an outcross.
• Outcrossing is done to overcome inbreeding depression.

(4) Crossbreeding:

• In crossbreeding superior males of one breed are mated with superior females of another breed.
• New animal breeds of desirable characters are developed by this method.
• Example : Hisardale breed of sheep is developed in Punjab by crossing Bikaneri ewes and Marino rams.

(5) Interspecific hybridization:

• It involves breeding of animals of two different but related species.
• It is used to produce animals with desirable characters from both the parents.
• e.g. Mule is a breed obtained from horse and donkey.
• It may not be always successful.

Question 2.
Which dairy products are prepared using microorganisms? How?
Answer:

1. Dairy products prepared using microorganisms are curds, yogurt, butter milk and cheese.
2. The starter or inoculum used in preparation of dairy products contains millions of lactic acid bacteria (LAB).
3. Curd is prepared by inoculating milk with Lactobacillus acidophilus. It ferments lactose sugar of milk into lactic acid. Lactic acid causes coagulation and partial digestion of milk protein casein. Thus, milk is changed into curd. It also checks growth of disease causing microbes.
4. Yogurt is produced by curdling milk with the help of Streptococcus thermophilus and Lactobacillus bulgaricus.
5. Buttermilk is the acidulated liquid left after churning of butter from curd, is called buttermilk.
6. During the preparation of cheese, the milk is coagulated with LAB. The curd formed is filtered and whey is separated. The solid mass is then ripened with growth of mould that develops flavour in it. Characteristic texture, flavour and taste of cheese are developed by different specific microbes.

The ‘Roquefort cheese is ripened by blue green mold Penicillium roquejortii. Camembert cheese is ripened by blue-green mold P. camembertii. The large holes in Swiss cheese are developed due to production of a large amount of CO₂ by a bacterium known as Propionibacterium shermanii.

Question 3.
What are biofertilizers? Explain what are the different types of biofertilizers with suitable examples.
Answer:

1. Biofertilizers are commercial ready to use live bacterial, cyanobacterial or fungal formulations.
2. When they are applied to plants, in soil or in composting pits, soil fertility increases. Biofertilizers are cost effective and eco-friendly.

Types of biofertilizers as follows:
1. Bacterial biofertilizers:

• Nitrogen fixing bacterial biofertilizers : They convert atmospheric nitrogen into compounds of nitrogen like ammonia, nitrites and nitrates. The nitrogen fixing bacteria Rhizobium forms symbiotic association with roots of leguminous plants. Free living nitrogen fixing bacteria are Azotobacter and Azospirillum.
• Phosphate solubilizing biofertilizers : They are the bacteria which solubilize the insoluble inorganic phosphate compound, e. g. Pseudomonas striata, Bacillus polymyxa, Agrobacterium, Microccocus, Aspergillus spp., etc.
• Bacteria are also involved in composting.

2. Cyanobacterial biofertilizers:

• They are nitrogen fixing biofertilizers.
• Heterocysts are the site of nitrogen fixation.
• Free living cyanobacteria are Anabaena, Nostoc, Tolypothrix, Plectonema, Oscillatoria.
• Anabaena and Nostoc have symbiotic relationship with lichens
• Anabaena is also symbiotically associated with Azolla and Cycas.

3. Fungal biofertilizers:

• Fungal biofertilizers are mycorrhizae which form symbiotic association with roots of higher plants. There may be ectomycorrhiza and endomycorrhiza (VAM).
• Ectomycorrhizae increase the absorptive surface area of rots and increase uptake of water and nutrients.
• Plants with endomycorrhizae grow well even in less irrigated lands.

4. Microbes involved in composting:
During composting, microorganisms break down organic matter into compost. E.g. bacteria, fungi, actinobacteria, protozoa and rotifers.

Question 4.
Describe in details different types of mycorrhizae.
Answer:
Mycorrhizae are fungi that form symbiotic association with the roots of higher plants in humid forests.
There are two types as follows:
(1) Ectomycorrhizae:

• Mycelium of these fungi form mantle on the surface of the roots.
• Due to this absorptive surface area of roots increases and uptake of water and nutrients (N, P Ca and K) improves.
• The plant vigour, growth and yield increase.
• Some hyphae may penetrate into the root and form hartig-net in ‘the intercellular spaces of root cortex.

(2) Endomycorrhizae:

• Fugal hypahe of endomycorrhizae penetrate the root cortex and form branched arbuscules intracellularly. They also form vesicles mostly in the intercellular spaces.
• Hence, they are called Vesiculo Arbuscular Mycorrhizae (VAM). Nowadays they are described as AM fungi.
• The plants associated with VAM grow luxuriantly in less irrigated lands.
• VAM increase the productivity of field.

Balbharti Maharashtra State Board 12th Biology Important Questions Chapter 10 Human Health and Diseases Important Questions and Answers.

Maharashtra State Board 12th Biology Important Questions Chapter 10 Human Health and Diseases

Multiple Choice Questions

Question 1.
The infectious stage of Plasmodium is …………………
(a) trophozoite
(b) sporozoite
(c) cryptozoite
(d) metacercaria
Answer:
(b) sporozoite

Question 2.
After birth, antibodies are transferred from mother to infant through …………………
(a) colostrum
(b) placenta
(c) blood
(d) tissue fluid
Answer:
(a) colostrum

Question 3.
Which cells give rise to T-lymphocytes?
(a) Thymocytes
(b) Bone marrow cells
(c) Erythrocytes
(d) Leucocytes
Answer:
(a) Thymocytes

Question 4.
Where is antigen D is present?
(a) On Rhesus factor
(b) On the surface of RBCs
(c) On A-antigen
(d) On AB-antigen
Answer:
(b) On the surface of RBCs

Question 5.
Erythroblastosis foetalis is caused when mother is …………………
(a) Rh +ve
(b) with antibody ‘a’
(c) Rh -ve
(d) with antibody ‘b’
Answer:
(c) Rh -ve

Question 6.
Which of the following is NOT a parasitic vector insect?
(a) Mosquito
(b) Housefly
(c) Honey bee
(d) Head louse
Answer:
(c) Honey bee

Question 7.
Which is the proper sequence in the developmental stages of Plasmodium?
(a) Merozoites → Sporozoite → Trophozoites → Schizonts
(b) Trophozoites → Merozoites → Sporozoite → Schizonts
(c) Sporozoite → Merozoites → Trophozoites → Schizonts
(d) Schizonts → Merozoites → Sporozoite → Trophozoites.
Answer:
(c) Sporozoite → Merozoites → Trophozoites → Schizonts

Question 8.
There is no vaccination on this disease till today.
(a) Typhoid
(b) Tuberculosis
(c) Polio
(d) AIDS
Answer:
(d) AIDS

Question 9.
Charas, hashish, ganja are obtained from …………………
(a) Papaver somnijerum
(b) Erythroxylum coca
(c) Atropa belladorta
(d) Cannabis sativa
Answer:
(d) Cannabis sativa

Question 10.
………………. Plant is used to obtain cocaine alkaloid.
(a) Marijuana
(b) Papaver somntferum
(c) Cannabis sativa
(d) Coca
Answer:
(d) Coca

Question 11.
………………… fish is released in the waterbody to prevent the spread of Malaria and Filaria.
(a) Pomfret
(b) Tilapia
(c) Gambusia
(d) Gold fish
Answer:
(c) Gambusia

Question 12.
The carcinogen that can cause vaginal cancer is …………………
(a) Vinyl chloride
(b) Diethylstilboestrol
(c) Mustard gas
(d) Cadmium oxide
Answer:
(b) Diethylstilboestrol

Question 13.
Prostate cancer can be caused due to exposure to …………………
(a) cadmium oxide
(b) mustard gas
(c) asbestos
(d) Nickel and chromium compounds
Answer:
(a) cadmium oxide

Question 14.
Choose the correct definition of health …………………
(a) Health is not contracting any disorder or disease.
(b) State of complete physical, mental and social well-being.
(c) Health is complete absence of any disease.
(d) Health is feeling good all the time.
Answer:
(b) State of complete physical, mental and social well-being

Question 15.
The interval between infection and appearance of disease symptoms is called …………………
(a) inoculation
(b) penetration
(c) infection period
(d) incubation period
Answer:
(d) incubation period

Question 16.
What is injected in vaccination ?
(a) Half killed pathogen
(b) Dead pathogens
(c) Live pathogens
(d) Readymade antibodies
Answer:
(a) Half killed pathogen

Question 17.
Who among the following is considered as father of immunology ?
(a) Ferdinand Kohn
(b) Robert Koch
(c) Louis Pasteur
(d) Edward Jenner
Answer:
(d) Edward Jenner

Question 18.
Who coined the term antibiotics ?
(a) Charles Darwin
(b) Louis Pasteur
(c) Alexander Fleming
(d) Selman Waksman
Answer:
(d) Selman Waksman

Question 19.
Who coined the term antibody?
(a) Selman Waksman
(b) Alexander Fleming
(c) Paul Ehrlich
(d) Edward Jenner
Answer:
(c) Paul Ehrlich

Question 20.
Widal test is used for the diagnosis of …………………
(a) Malaria
(b) Typhoid
(c) Diabetes mellitus
(d) HIV/AIDS
Answer:
(b) Typhoid

Question 21.
Which bacterial genus out of the following is the common pathogen causing pneumonia ?
(a) Streptococcus sps
(b) Lactobacillus sps
(c) Pseudomonas sps
(d) Salmonella sps
Answer:
(a) Streptococcus sps

Question 22.
Given below are some statements. Which among them are symptoms of pneumonia ?
(i) Greenish, yellow sputum coughed out.
(ii) Hepatomegaly and hypoglycemia.
(iii) High fever with shaking chills.
(iv) Thickening of skin and underlying tissues.
(v) Stabbing chest pain with shortness of breath.
(vi) Mood swings and joint pains along with nausea and vomiting.
(a) (i), (ii), (iii), (iv)
(b) (i), (iii), (v), (vi)
(c) (i), (ii), (iv), (vi)
(d) (ii), (iii), (iv), (v)
Answer:
(b) (i), (hi), (v), (vi)

Question 23.
Which of the following is not the common way to prevent common cold ?
(a) Using hand sanitizers
(b) Blowing nose in open
(c) Staying away from people suffering from cold
(d) Sipping warm water
Answer:
(b) Blowing nose in open

Question 24.
Common cold is not cured by antibiotics because it is …………………
(a) caused by a virus
(b) caused by a Gram-positive bacterium
(c) caused by a Gram-negative bacterium
(d) not an infectious disease
Answer:
(a) caused by a virus

Question 25.
Motile zygote of Plasmodium occurs in …………………
(a) gut of female Anopheles
(b) salivary glands of Anopheles
(c) Human RBCs
(d) Human liver
Answer:
(a) gut of female Anopheles

Question 26.
Haemozoin is …………………
(a) a precursor of haemoglobin
(b) a toxin from Streptococcus
(c) a toxin from Plasmodium
(d) a toxin from Hemophilus
Answer:
(c) a toxin from Plasmodium

Question 27.
Vaccination against malaria is not possible because …………………
(a) they produce antibodies and antitoxins
(b) they do not produce antibodies and antitoxins
(c) antibodies resistant to vaccines are produced
(d) none of these
Answer:
(b) they do not produce antibodies and antitoxins

Question 28.
The active form of Entamoeba histolytica feeds upon …………………
(a) blood only
(b) erythrocytes, mucosa and submucosa of colon
(c) mucosa and submucosa of colon only
(d) food in intestine
Answer:
(b) erythrocytes, mucosa and submucosa of colon

Question 29.
Eating unwashed and raw green leafy vegetables grown along the railway tracks in Mumbai may cause …………………
(a) malaria
(b) influenza
(c) amoebic colitis
(d) ringworm
Answer:
(c) amoebic colitis

Question 30.
Which method of water purification can terminate amoebae ?
(a) Chlorination
(b) Sedimentation
(c) Filtration
(d) Boiling
Answer:
(d) Boiling

Question 31.
Which of the following measures should be taken to control amoebic dysentery ?
(A) Using insecticidal sprays to kill flies.
(B) Not allowing stagnant water to be accumulated over a long time.
(C) To avoid eating uncovered food.
(D) Drinking only boiled water.
(E) Eating plenty of fruits.
(a) (A) (C) (D)
(b) (A) (B) (D)
(c) (B) (C) (E)
(d) (A) (B) (E)
Answer:
(a) (A) (C) (D)

Question 32.
Which of the following should be avoided for endemic spread of amoebiasis ?
(a) Cleaning bathroom taps and toilet seats with disinfectants.
(b) Washing hands and using hand sanitizers.
(c) Proper sewage disposal and treatment.
(d) Eating uncovered roadside food.
Answer:
(d) Eating uncovered roadside food.

Question 33.
Name the disease in which the genital organs are grossly affected due to infective helminth.
(a) Ascariasis
(b) Ring worm
(c) Scabies
(d) Filariasis
Answer:
(d) Filariasis

Question 34.
Find the odd organism:
(a) Wuchereria bancrofti
(b) Brugia malayi
(c) Brugia timori
(d) Ascaris lumbricoides
Answer:
(d) Ascaris lumhricoides

Question 35.
When is hydrocele formed in a man ?
(a) When testis are not functioning properly.
(b) When scrotum is infected with filarial worms.
(c) When testis are injured due to accident.
(d) When there is water accumulation in testis.
Answer:
(b) When scrotum is infected with filarial worms

Question 36.
Which medicine is used for eradicating microfilariae from endemic areas ?
(a) Diethyle carbamacine
(b) Mebendazole
(c) Albendazole
(d) Rimfampcin
Answer:
(a) Diethyle carbamacine

Question 37.
Which of the following fungi are causative organisms of ringworm ?
(a) Microsporum
(b) Candida
(c) Thrush
(d) Tinea pedis
Answer:
(a) Microsporum

Question 38.
On which material present on the outer skin surfaces of the human body does the fungus causing infections feed on ?
(a) Melanin
(b) Keratin
(c) Lignin
(d) Suberin
Answer:
(b) Keratin

Question 39.
Which of the following statements is correct ?
(a) Fungus grows well on dry skin.
(b) Fungus cannot survive on the outside of the hair shafts.
(c) Fungus thrives well on the warm and moist skin.
(d) Nails can never show fungal infections.
Answer:
(c) Fungus thrives well on the warm and moist skin.

Question 40.
Which of the following pair is viral diseases ?
(a) Common cold, AIDS
(b) Dysentery, Common cold
(c) Typhoid, Tuberculosis
(d) Ringworm, AIDS
Answer:
(a) Common cold, AIDS

Question 41.
Which one of the following glands is often referred in relation with AIDS ?
(a) Thymus
(b) Adrenal
(c) Thyroid
(d) Pancreas
Answer:
(a) Thymus

Question 42.
The first patient of AIDS was detected in India in …………………
(a) 1980
(b) 1986
(c) 1990
(d) 1996
Answer:
(b) 1986

Question 43.
Why is it said that for AIDS prevention is the only cure ?
(a) AIDS does not have any cure, once it is contracted.
(b) By prevention AIDS cannot be cured.
(c) AIDS can be cured by proper medication and vaccination.
(d) Only prevention helps as there is no cure for AIDS.
Answer:
(d) Only prevention helps as there is no cure for AIDS.

Question 44.
After a person is detected to be having AIDS by ELISA test, which is the next confirmatory test ?
(a) Western blot
(b) Southern blot
(c) PCR
(d) Northern blot
Answer:
(a) Western blot

Question 45.
What is full form of ELISA ?
(a) Enzyme Linked Inductive Assay
(b) Enzyme Linked Iron Sorbent Assay
(c) Enzyme Linked Immunosorbent Assay
(d) None of the above
Answer:
(c) Enzyme Linked Immunosorbent Assay

Question 46.
The possible ways of transmission of AIDS are …………………
(A) Intimate sexual contact
(B) Hugging and kissing
(C) Blood transfusion without properly checking it
(D) Eating from the same plate
(E) Sharing bed linen
(F) Transplacental infection from infected mother
(G) Sharing same tattoo gun and syringes
(a) (A), (C), (F), (G)
(b) (B), (D), (E), (G)
(c) (C), (D), (E), (F)
(d) (A), (B), (C), (D)
Answer:
(a) (A), (C), (F), (G)

Question 47.
Which one of the following statements is correct ?
(a) Benign tumours show the property of metastasis.
(b) Heroin accelerates body functions.
(c) Malignant tumours may exhibit metastasis.
(d) Patients who have undergone surgery are given cannabinoids to relieve pain.
Answer:
(c) Malignant tumours may exhibit metastasis.

Question 48.
Heroin or smack is chemically …………………
(a) diclofenac
(b) diacetyl morphine
(c) benzodiazepine
(d) amphetamines
Answer:
(b) diacetyl morphine

Question 49.
Ecstasy is a drug that is used in most of the Rev parties which is chemically a derivative of …………………
(a) Barbiturates
(b) Amphetamines
(c) Catecholamine
(d) Morphine
Answer:
(b) Amphetamines

Question 50.
From which plant is charas obtained?
(a) Cannabis sativa
(b) Erythroxylum coca
(c) Papaver somniferum
(d) Atropa belladonna
Answer:
(a) Cannabis sativa

Question 51.
Opium is obtained from the latex of the unripe fruits of …………………
(a) Cannabis sativa
(b) Thea siensis
(c) Papaver somniferum
(d) Erythroxylon coca
Answer:
(c) Papaver somniferum

Question 52.
Use of Cannabis products results in …………………
(a) depressed brain activity and feeling of calmness
(b) suppressed brain function and relief of pain
(c) stimulation of nervous system, increased alertness and activity
(d) alteration in perception, thoughts and feelings
Answer:
(d) alteration in perception, thoughts and feelings

Question 53.
Marijuana, ganja and LSD are …………………
(a) narcotics
(b) stimulants
(c) hallucinogens
(d) all of these
Answer:
(c) hallucinogens

Question 54.
What is the source of LSD ?
(a) Poppy seeds
(b) Datura plant
(c) Sugar
(d) Claviceps purpurea
Answer:
(d) Claviceps purpurea

Question 55.
Narcotics are …………………
(a) amphetamines and caffeine
(b) morphine and heroine
(c) LSD and cocaine
(d) barbiturates and benzodiazepine
Answer:
(b) morphine and heroine

Question 56.
Which is an incorrectly matched pair ?
(a) LSD – Ergot fungus
(b) Heroin – Opium
(c) Amphetamines – Depressant
(d) Benzodiazepine – Calmpose tablets
Answer:
(c) Amphetamines – Depressant

Question 57.
Choose the incorrect statement
(a) The excessive use of anabolic steroids cause severe acne.
(b) In both the sexes there is increased aggressiveness and mood swings, due to steroids.
(c) In females, anabolic steroids cause breast enlargement.
(d) In males, anabolic steroids cause enlargement of prostate gland.
Answer:
(c) In females, anabolic steroids cause breast enlargement.

Question 58.
Who are the first ones to note the danger signs of drug or alcohol abuse in the adolescents ?
(a) Alert parents and teachers
(b) Neighbours
(c) Relatives
(d) Doctors
Answer:
(a) Alert parents and teachers

Question 59.
Who can give professional help for the deaddiction?
(a) Highly qualified psychiatrist
(b) Parents
(c) Teachers
(d) Friends
Answer:
(a) Highly qualified psychiatrist

Match the columns

Question 1.

Answer:

Question 2.

Answer:

Classify the following to form Column B as per the category given in Column A

Question 1.
Benzyl penicillin, Chloromycetin, Mebendazole, Levamisole, Pyrimethamine Ampicillin, Ty21a vaccine, Sulfadoxine.

Answer:

Question 2.
Lung cancer, Pituitary, Spleen, Skin cancer, Cancer of adipose tissue, lymph nodes, Adrenal, Bone tumour.

Answer:

Very Short Answer Questions

Question 1.
By which process T-cells and B-cells are produced?
Answer:
T-cells and B-cells are produced from the stem cells called haemocytoblasts, in bone marrow of adults and in liver of the foetus, by the process of haematopoiesis and in the bone marrow in adult.

Question 2.
What is a hinge?
Answer:
Hinge is the region of Y-shaped structure, holding arms and stem of antibody where four polypeptide chains of antibody are held together by disulfide bonds (-s-s-) to form a ‘Y’-shaped structure.

Question 3.
What is epitope?
Answer:
Epitope is antigenic determinant, which is present on antigens.

Question 4.
What is paratope?
Answer:
Paratope is antigen binding site that is present on the antibodies.

Question 5.
Which antigen is present in Rh +ve person?
Answer:
Antigen D is present in Rh +ve person.

Question 6.
Give the role of flushing action of lachrymal secretions.
Answer:
The conjunctiva is freed from foreign particles by the flushing action of lachrymal secretions.

Question 7.
What happens when lachrymal secretion is absent in eyes?
Answer:
Eyes become susceptible to infection when lachrymal secretion is absent.

Question 8.
In tears which antibacterial substance is present?
Answer:
Lysozyme is the antibacterial substance present in the tears.

Question 9.
Which kind of immunity is provided by vaccination?
Answer:
Artificial acquired active and passive immunity is provided by vaccination.

Question 10.
Who was Edward Jenner?
Answer:
Edward Jenner was the British scientist who developed cowpox vaccine for the protection against small pox virus.

Question 11.
Mrunmayi is called universal blood acceptor. What is her blood group?
Answer:
Blood group of Mrunmayi is AB.

Question 12.
What are antigens?
Answer:
Different foreign substances that invade the body and are capable of stimulating an immune response are called antigens.

Question 13.
In which animal Rh factor was discovered at first?
Answer:
Rh factor was first discovered in Rhesus monkey for the first time.

Question 14.
What is elephantiasis?
Answer:
Elephantiasis is one of the symptoms of lymphatic filariasis, in which there is thickening of skin and underlying tissues due to presence of malarial parasite.

Question 15.
What is dermatophytosis ?
Answer:
Dermatophytosis is a clinical condition in which fungal infection of skin occur in humans, pets and cattle which is commonly called as ringworm.

Question 16.
What is sporozoite?
Answer:
Sporozoite is a developmental stage of Plasmodium produced by rupture of oocyst. Sporozoite can enter the bloodstream in human body and then infect hepatocytes or liver cells, where they multiply into merozoites.

Question 17.
Why does male mosquito not spread Malaria?
Answer:
Male mosquito feed only on plant sap and not blood of human beings; therefore it does not spread Malaria.

Question 18.
Where does Plasmodium reproduce asexually?
Answer:
Plasmodium reproduce asexually in the liver cells and red blood cells of infected human being.

Question 19.
Where does Plasmodium reproduce sexually?
Answer:
Plasmodium undergoes sexual reproduction by the process of fertilization and development in the intestine of mosquito.

Question 20.
Which fish can be used for mosquito control?
Answer:
Gambusia fish can be used for mosquito control.

Question 21.
What is arthralgia?
Answer:
Arthralgia means joint pains.

Question 22.
What do you mean by hepatomegaly?
Answer:
Hepatomegaly means enlargement of liver.

Question 23.
Which organism yields LSD?
Answer:
Ergot fungus, Claviceps purpurea yield LSD.

Question 24.
Enlist various types of barriers which prevent entry of foreign agents into the body.
Answer:

1. Epithelial surface
2. Antimicrobial substances in blood and tissues
3. Cellular factors in innate immunity
4. Fever
5. Acute phase proteins (APPs).

Question 25.
Which is the gastro-intestinal disease by which 15% Indian population is affected?
Answer:
Amoebiasis or amoebic dysentery is the gastro-intestinal disease by which 15% Indian population is affected.

Question 26.
What are the anti-helminthic drugs which are used in treatment of Ascariasis?
Answer:
Anti-helminthic drugs like Piperazine, Mebendazole, Levamisole, Pyrantel are used against Ascaris lumbricoidies.

Question 27.
Which are the diseases that can be avoided by eradication of mosquitoes in your area?
Answer:
Malaria, dengue, chikungunya and filariasis or elephantiasis can be avoided by eradication of mosquitoes.

Define the following

Question 1.
Serology
Answer:
A branch of immunology which deals with the study of antigen-antibody interactions is called serology.

Question 2.
Hygiene
Answer:
Hygiene is the science of health, which aims at preserving, maintaining and improving the health of an individual or the community as a whole.

Question 3.
Disease
Answer:
Disease is a condition of disrupted or deranged functioning of one or more organs or systems of the body caused due to infection, detective diet or heredity.

Question 4.
Immune system
Answer:
The system which protects us from various infectious agents is called immune system.

Question 5.
Resistance
Answer:
Resistance is an ability to ward off damage or disease through our defence mechanism.

Question 6.
Immunity
Answer:
The immunity is defined as the general ability of a body to recognize and neutralize or destroy and eliminate foreign substances or resist a particular infection or disease.

Question 7.
Antibody
Answer:
The protective chemicals produced by immune cells in response to antigens is called antibodies.

Question 8.
Opsonisation
Answer:
The process of coating of bacteria to facilitate their subsequent phagocytosis by macrophages is called opsonisation.

Question 9.
Pathogen
Answer:
Pathogen are living agents such as viruses, ricketssia, bacteria, fungi, protozoans, helminth and certain insect larvae which are capable of causing diseases.

Question 10.
Parasite
Answer:
An organism that lives in or on another organism called host and takes its nourishment from it (host) is called parasite.

Question 11.
Pathogenicity
Answer:
The ability of an organism to enter a host and cause a disease is called pathogenicity.

Question 12.
Infectious disease
Answer:
The disease which is transmitted from infected person to another healthy person either directly or indirectly is called infectious disease or communicable disease.

Question 13.
Non-infectious disease
Answer:
The disease that cannot be transmitted from one infected person to another healthy person, either directly or indirectly is called non infectious or non-communicable disease.

Question 14.
Innate immunity
Answer:
Innate immunity is defined as the resistance to infections that an individual possesses due to his or her genetic make-up and thus it is inborn defence mechanism present naturally in the body.

Question 15.
Acquired immunity
Answer:
The resistance developed during lifetime is called acquired immunity.

Question 16.
APP proteins
Answer:
APP proteins or acute phase proteins are certain collection of plasma proteins which are suddenly increased by the infection caused after injury.

Question 17.
Incubation period
Answer:
Incubation period is the time interval from the invasion of a pathogen to the development of clinical manifestations or symptoms.

Name the following

Question 1.
Name the cell that produces lymphokines.
Answer:
Helper T-cells

Question 2.
Blood group systems in human beings.
Answer:
ABO, Rh, Duffy, Kidd, Lewis, P MNS, Bombay blood group.

Question 3.
Types of sarcoma.
Answer:

1. Osteosarcoma (bone)
2. Myosarcoma (muscle)
3. Chondrosarcoma (cartilage)
4. Liposarcoma (adipose tissue)

Question 4.
Therapies used for treatment of cancer.
Answer:

1. Chemotherapy
2. Radiotherapy
3. Surgery
4. Immunotherapy
5. Supportive therapy

Question 5.
Name the term for the transmission of HIV from pregnant mother to foetus.
Answer:
Transplacental.

Question 6.
Factors that maintain good health.
Answer:

1. Balanced diet
2. Personal hygiene
3. Regular exercise
4. Right attitude of mind
5. Good habits.

Question 7.
Two examples of ascaricides.
Answer:
Mebendazole and Albendazole, etc.

Question 8.
Two vaccines for typhoid.
Answer:

1. Oral Ty21a
2. Injectable Typhoid polysaccharide vaccine or Typhium vi/ Typherix.

Question 9.
Parasites causing lymphatic filariasis.
Answer:

1. Wuchereria bancrojti
2. Brugiamalayi
3. Brugia timori.

Question 10.
Parasites causing Subcutaneous Filariasis.
Answer:

1. Loa loa
2. Mansonella spp.

Question 11.
Name the scientists who discovered AB blood group?
Answer:
Decastallo and Sturti

Distinguish between the following

Question 1.
Inborn immunity and acquired immunity.
Answer:

Question 2.
Communicable and non-communicable diseases.
Answer:

Question 3.
Ascariasis and Filariasis.
Answer:

Short answer questions

Question 1.
Despite constant exposure to variety of pathogens, why do most of us remain healthy?
Answer:

1. All human beings are exposed to various foreign bodies, including infectious agents like bacteria, viruses, etc. which are called pathogens.
2. But human body can resist almost all types of these pathogens.
3. For this purpose, there is immune system which protects us from various infectious agents.
4. There is resistance and prevention of the damage or disease, through our defence mechanisms.
5. Thus, despite constant exposure to variety of pathogens, most of us remain healthy.

Question 2.
What are the unique features of acquired immunity?
Answer:
Following are the unique features of acquired immunity:

1. Specificity : Production of specific antibody or T-lymphocyte against a particular antigen/ pathogen is called specificity.
2. Diversity : Ability to recognize vast variety of diverse pathogens or foreign molecules by immunity is called diversity.
3. Discrimination between self and non¬self : Acquired immunity can differentiate between own body cells (self) and foreign (non-self) molecules.
4. Memory : The first immune response upon encounter of a specific foreign agent and its elimination is retained as a memory. This results in quicker and stronger immune response when the same pathogen is encountered again.

Question 3.
Describe the polypeptide chains seen in the structure of an antibody.
Answer:

1. There are four polypeptide chains which make the antibody.
2. There are two heavy or H-chains and two light or L-chains.
3. Each chain has two distinct regions, the variable region and the constant region.
4. Variable regions carry the antigen binding site or paratope.
5. This part of antibody recognizes and bindsto the specific antigen to form an antigen- antibody complex.

Question 4.
Which are the antimicrobial substances in blood and tissues?
Answer:

1. There are more than 30 serum proteins, circulating in the blood in an inactive state, which forms the complement system.
2. ‘Complement cascade’ is activated by presence of pathogens and thus they eliminate pathogens.
3. Cells which are affected by viruses secrete interferons which are a class of cytokines. These soluble proteins attack the pathogens.
4. Some leucocytes stimulate other cells to protect themselves from viral infection.

Question 5.
Is developing fever a bad sign or a good action? Explain.
Answer:

1. Fever is the innate immunity mechanism. When there is fever, the body rises.
2. This is in response to infection in a natural way.
3. Developing fever is a natural defence mechanism.
4. Fever helps to accelerate the physiological processes by which the invading pathogens are destroyed.
5. Fever stimulates the production of interferon and helps in recovery from viral infections.
6. Taking all these points into consideration, getting fever is a good action that innate immunity is working properly, however, entry of pathogen in the body causing illness is a bad sign.

Question 6.
With the help of a chart explain the compatibility of human blood groups.
Answer:
Different types of blood groups:

1. Person with blood group A can donate blood to persons having blood group A or AB and receive blood from A or O.
2. Person with blood group B can donate blood to persons having blood group B or AB and receive blood from B or O.
3. Person with blood group O can donate blood to all the persons having blood group either A, B, AB or O, because blood group O is universal donor. But can receive blood only from person having blood group O.
4. Person with blood group AB can donate blood to only AB but can receive blood from all the persons having blood group either, A, B, O or AB because AB is universal recipient.

Question 7.
The blood group of Krutika is O Rh +ve. What would be the possible blood groups of her parents?
Answer:

1. Krutika has O blood group, therefore her genotype is I°I°.
2. Her parents can be of following combinations.
3. They may be having blood group A or B with heterozygous genotype respectively, i.e. IAI° and IBI°. If both of them are heterozygous, having either A or B blood group, Krutika can be of O type.
4. Other possibility is both the parents have to be O.
5. For being Rh positive, her at least one parent should be Rh positive. Rh negative is a recessive phenotype and hence needs double dose of these genes.

Question 8.
Can a person with blood group O Rh+ve donate blood to a patient with blood group O Rh-ve? Why?
Answer:
No. blood group O may be common to both donor and recipient but their Rh factor is different. A person with RH+ve blood cannot donate to a patient with Rh-ve blood group. In Rh+ve blood there is antigen D. This antigen D when enters the body of recipient, there are production of anti-RH antibodies in his or her body. These anitibodies with cause agglutination of the Rh +ve blood which will be given to the patient. This agglutination will cause clots inside the vital organ of the recipient and the death may follow.

Question 9.
Why do we suffer from common cold repetitively in our life, but other viral diseases like Influenza or Small pox only once?
Answer:
Influenza infection causes production of antibodies in our body, once the virus attacks us. Therefore, second encounter with the virus may not cause effect. But in case of common cold, large number of different virus families are responsible for developing infection of common cold. Many a times different allergens are also inducing agents for common cold. Thus we may suffer from common cold again and again.

Question 10.
What are the symptoms of pneumonia?
Answer:

1. Main symptoms of infectious pneumonia are cough producing greenish or yellow sputum or phlegm and a high fever with chills.
2. Shortness of breath, stabbing chest pain, coughing up blood, headaches, sweaty and clammy skin, loss of appetite, fatigue, blueness of the skin, nausea, vomiting, mood swings and joint pains or muscle aches are some other symptoms.

Question 11.
What is the diagnosis and treatment of filariasis? How can we control this disease ?
Answer:
I. Diagnosis and Treatment : For the patient, diethyl-carbamazine citrate is the drug used for twice a day for three weeks. Thereafter for five days every six months the same treatment is repeated. This becomes effective against filarial worms.

II. Prevention and Control:

1. Mosquito eradication should be done for controlling filariasis.
2. In the areas with mosquitoes, avoid mosquito bite by using mosquito nets and insect repellents.

Question 12.
What are the signs and symptoms of filariasis?
Answer:
Signs and symptoms of filariasis:

1. As the lymphatic drainage does not take place, there is oedema with thickening of skin and underlying tissue.
2. Extremities like legs, arms, breasts, scrotum, etc. are affected by nematode causing lymphatic filariasis, i. e. Wuchereria bancrofti.
3. Lymph vessels and lymph nodes are enlarged and swollen.
4. Elephantiasis is seen in which limbs are swollen like legs of elephant.
5. Lymphoedema, i.e. accumulation of lymph fluid is seen in tissue causing swelling.
6. Hydrocele condition develops in which testis are enlarged due to accumulation of lymphatic fluid in testis.

Question 13.
What are the various ways in which mosquitoes can be eradicated from any area?
Answer:
Eradication of mosquitoes:

1. Removal of all stagnant water pools around the houses.
2. If such water bodies are there, they should be sprayed with insecticides.
3. But better option which is eco-friendly is releasing mosquito eating fish like Gambusia or Tilapia.
4. Use of mosquito repellent plants like Citronella. Use of coils and repellent creams.
5. Fumigation of the area to kill the mosquito.
6. Aedes sps. breed in man-made containers, especially plastic and cement tanks. Care should therefore be taken to dispose such containers properly. Water should not be accumulated in them.

Question 14.
What precautions will you take if you are travelling in an area which has lot of mosquitoes?
Answer:

1. Avoiding areas where mosquitoes are in more concentration.
2. Carrying mosquito repellent creams or coils.
3. Use of mosquito nets and other fumigation devices.
4. Wearing full clothing in light colours.
5. Staying indoors when mosquitoes are swarming, especially in the evening.
6. Taking anti-malarial pills as a precautionary measure.

Question 15.
Deaddiction may be difficult but not impossible. Collect information about NGOs, working in the field of deaddiction.
Answer:
There are many NGOs that work in the field of deaddiction. In different cities, there are different organizations. Even the central Government has started helpline number 1800-11-0031 for those drug and alcohol addicts who need help to come out of these addictions. Muktangan in Pune is one such reputed organization which does the great work in the field of deaddiction.

Question 16.
What are the most common warning signs of drug and alcohol abuse among youth ?
Answer:
The most warning signs of addictions are as follows:

1. Drop in academic performance, absenteeism from school or college.
2. No interest in personal hygiene and hobbies.
3. Withdrawal from the society, increased tendency of isolation and depression.
4. Aggressive and rebellious behaviour resulting into strained relationships with family and friends.
5. Fatigue and change in sleeping and eating habits.
6. Fluctuations in weight, appetite, deteriorating health, etc.

Question 17.
What are the preventive measures for malaria?
Answer:
Preventive measures of malaria :

1. Transmission of malarial parasite can be reduced by preventing mosquito bites. Therefore, mosquitoes should be controlled or totally eradicated.
2. This can be done by using of mosquito nets and insect repellents.
3. Mosquito control measures such as spraying insecticides inside houses and draining stagnant water where mosquitoes lay their eggs.
4. The mosquito larvae can be eradicated by releasing Gambusia fish which can feed upon these larvae.
5. Vaccine against malaria is also under preparation.

Question 18.
How does Entamoeba histolytica causes amoebiosis ?
Answer:

1. Amoebiosis is spread through ingestion of the cyst form of Entamoeba histolytica. This is a commensal organism.
2. Cyst is a semi-dormant and hardy structure found in faeces of infected person.
3. Non-encysted amoebae are called trophozoites. The trophozoites die quickly after leaving the body but may also be present in faeces.
4. Trophozoites are rarely the source of new infections.
5. The infection may remain asymptomatic for many days as Amoeba can remain latent in the gastrointestinal tract.

Question 19.
Describe the signs and symptoms of amoebiasis.
Answer:
Amoebiasis shows following common symptoms:

1. Diarrhoea, flatulence, stool with mucus and abdominal pains (cramps) are common.
2. Stool sticky with mucus and blood.
3. Amoebae form cysts in the liver, in such case there is hepatomegaly, i.e. enlargement of liver.
4. Liver shows amoebic liver abscess accompanied with fever and pain in right side of the abdomen.

Question 20.
How can amoebiasis be prevented?
Answer:
Prevention of amoebiasis is to be done at two levels, viz. at home and at endemic level.
1. Prevention of the spread of amoebiasis at the home level:

• Washing hands with soap and water after using the toilet or changing a baby’s diaper and before handling and eating food.
• Cleaning bathrooms and toilets properly with germicides.
• Avoiding raw vegetables when in endemic areas where they are grown in soil fertilized by human faeces.
• Boiling and purifying the drinking water.

2. Prevention of the spread of amoebiasis at endemic level:

• Avoiding consumption of street foods especially in public places.
• Following good sanitary practice, as well as using proper sewage disposal or treatment.
• E. histolytica cysts are usually resistant to chlorination; therefore sedimentation and filtration of water supplies are necessary to reduce the incidence of infection.
• Avoiding shared towels or face washers.

Question 21.
Describe the symptoms of ascariasis.
Answer:

1. After infection by Ascaris lumbricoides, there is appearance of eggs in stools in 60 – 70 days.
2. In larval ascariasis, symptoms are seen in 4-16 days after infection.
3. The final symptoms are gastrointestinal discomfort, colic and vomiting, fever and appearance of live worms in faeces.
4. Some patients may have pulmonary symptoms. Inflammation of alveolar walls is seen. This is known as pneumonitis.
5. Some may show neurological disorders during migration of the larvae.
6. Loss of appetite which reflects in weight loss.
7. A bolus of worms may obstruct the intestine.
8. Larvae that migrate may also cause eosinophilia, i.e. increase in number of eosinophils.

Question 22.
What are the preventive measures against ascariasis?
Answer:

1. Prevention of ascariasis can be done by adopting the following measures :
2. Use of proper toilet facilities.
3. Safe disposal of excreta.
4. Protection of food from dirt and soil.
5. Washing of vegetables before cooking and avoiding eating raw, unwashed vegetables and fruits.
6. Hand washing and use of safe food. Observing personal hygiene.
7. Use of pharmaceutical drugs such as Mebendazole and Albendazole can kill Ascaris.

Question 23.
Discuss the clinical manifestation of AIDS.
Answer:
There are four stages of clinical manifestations or symptoms of AIDS.

1. Stage I : This is initial infection with the virus and formation of antibodies, usually 2-8 weeks after initial infection.
2. Stage II : In this stage the person is asymptomatic carrier. Incubation takes place with a period ranging for 6 months to 10 years.
3. Stage III : This is called AIDS related complex (ARC). In this stage, one or more of the following clinical signs are seen. E.g. Recurrent fever for longer than one month, fatigue, unexplained diarrhoea, night sweats, shortness of breath, loss of more than 10 per cent body weight, etc.
4. Stage IV : This is the end stage in which patient shows full blown AIDS. Thus it is called the end stage of HIV infection. Life threatening opportunistic infections (like pneumonia, tuberculosis, Kaposi sarcoma, etc.) are easily caught during this period.

Question 24.
Through which modes HIV infection does not spread?
Answer:

1. HIV does not spread through casual contact such as hugging, etc.
2. Insect bite such as mosquito bites does not transmit HIV.
3. Participation in sports is not the mode by which HIV transmits.
4. Contact between articles used by AIDS patient, a hand shake with him or her does not transmit HIV
5. HIV infections do not occur through swimming pool or by sharing clothes, utensils, etc.

Question 25.
Write about laboratory diagnosis and treatment of AIDS.
Answer:
I. Laboratory diagnosis :

1. There are two tests for diagnosis of AIDS.
2. First test is ELISA (Enzyme-Linked Immunosorbent Assay) which is used to detect the HIV antibodies.
3. The second confirmatory test is Western Blot, which is used to weed out any false positive results. It is a highly specific test.
4. It is based on detecting specific antibody to viral core protein and envelope glycoprotein.

II. Treatment of AIDS:

1. AIDS cannot be cured.
2. Antiretroviral drugs are used to reduce the viral load and prolong the life of HIV patient. E.g. Antiretroviral therapy (ART) uses drugs such as TDF (tenofovir), EFV (Efavirenz), Lamivudine (3TC), etc.

Question 26.
Describe the structure of HIV with a suitable diagram.
Answer:

1. Human Immunodeficiency Virus or HIV is spherical and 100 to 140 nm in diameter.
2. It has centrally located two ss RNA molecules along with reverse transcriptase enzymes.
3. There are coverings of two layers of proteins. The outer layer formed by matrix protein (pi7) while in inner layer is of capsid protein (p24).
4. An additional layer of lipids is seen over the matrix protein layers. This layer is impregnated with glycoprotein GP120 and GP41.
   

Question 27.
What are the modes of transmission of HIV or AIDS?
Answer:
The transmission of HIV occurs through following routes:

1. Sexual relations, mainly unsafe sexual contact including oral, vaginal and anal sex.
2. Through blood and blood products either by blood transfusions or sharing needles and syringes.
3. Transplacental From pregnant mother to her foetus through placenta. Nursing mother can also transmit HIV to her baby through lactation.
4. Spreading the virus is very rare in case of accidental needle injury, artificial insemination with infected donated semen and transplantation with infected organs.
5. HIV is seen in urine, tears, saliva, breast milk and vaginal secretions but unless these body fluids enter the injuries and wounds, transmission is not easy.

Question 28.
What are the measures of prevention and control of AIDS ?
Answer:

1. Preventive measures : AIDS has no cure, hence prevention is the best choice. The
   following steps help in preventing this dreadful disease.
2. High risk group people should be educated about HIV transmission. They should never donate blood.
3. Use of disposable needles and syringes should be done with proper disposal.
4. Risky sexual habits should be avoided.
5. Tooth brushes, razors, other articles that can become contaminated with blood should not be shared.
6. Blood should be screened before receiving it.
7. Routine screening of blood and semen donors, organ donors (kidney, liver, lung, cornea), and patients undergoing haemodialysis must be done.
8. Pregnant women or those women who are contemplating pregnancy should be regularly screened.

Question 29.
Explain the ill-effects of opioids and cannabinoids on health.
OR
What are harmful effects of drug abuse?
Answer:

1. Opioids bind to specific opioid receptors which are present in central nervous system and gastrointestinal tract. Some opioids e.g. heroin act like depressants and slow down all the body functions.
2. Cannabinoids have the capacity to interact with receptors present in the brain. Inhalation or ingestion of cannabinoids such as marijuana, hashish, charas and ganja have adverse effect on cardiovascular system.
3. Cannabinoid like LSD causes hallucinations.
4. All these substances are addictive and hence cause adverse effects on the body and health.

Question 30.
Give the adverse effects of opioids, cannabinoids and morphine on human health.
Answer:
1. Opioids:

• Opioids bind to specific opioid receptors present in the central nervous system and in gastrointestinal tract.
• They are depressants and slow down the body functions.

2. Cannabinoids:

• Cannabinoids interact with receptors in the brain.
• They affect cardiovascular system of the body.

3. Morphine:

• Morphine is an effective sedative and pain killer when used for medicinal purpose.
• When abused it affects physical, physiological and psychological functions.

Give reasons

Question 1.
Vaccines are safe.
Answer:
During their manufacture, vaccines are rigorously tested. Many rounds of study, examination and research are carried out before they are used for general public. Extensive research and evidences are gathered to check their safety. Sometimes, some vaccines produce side effects but these are rare and mild. Hence vaccines are considered to be safe.

Question 2.
Innate immunity is also known as non-specific immunity.
Answer:
Innate immunity is non-specific because it does not depend on previous exposure to foreign substances. It is inborn capacity of the body to resist the pathogen that causes the disease. It is natural immunity and hence it remains non-specific, trying to protect the body in case of any invasion of foreign body.

Question 3.
Vaccination is important for preventing pneumonia.
Answer:
Vaccinations for pneumonia are available against Haemophilus influenzae and Streptococcus pneumoniae. If given earlier in life, they reduce the chances of catching pneumococcal infections. The deaths can be prevented which are common due to lung infections. Since it is a common and chronic j disease for all age groups, for the prevention one must take vaccination.

Question 4.
Common cold is the most frequent ! infectious disease in humans.
Answer:
Common cold is caused by virus which is abundantly present in congested city environments. The upper respiratory tract is infected due to these rhinoviruses and corona viruses. Average adult contracts such infections 2 to 4 times in a year while children capture it 6 to 12 times in a year. Therefore, it is said to be the most frequent infectious disease of human beings.

Question 5.
Typhoid is food and water-borne disease.
Answer:
Typhoid is caused due to Salmonella typhi which isa Gram-negative bacterium, transmitted from a patient or carrier to another healthy person through contaminated food or water. Flying insects, mostly houseflies transmit the bacteria from faeces to the food. Poor hygienic habits and improper public sanitation system spreads typhoid. Therefore, it is said to be food and water-borne disease.

Question 6.
Malignant tumour is more dangerous than benign tumour.
Answer:
Malignant tumour cells can show metastasis and hence can spread far and wide in the body, affecting other healthy cells and tissues. They are difficult to cure by any therapy as one does not know exact location of the cancerous cells. They also produce variety of symptoms depending on their i location. On the contrary, benign tumours can be treated surgically. Since they are covered by a cyst like membrane, the cancerous cells do not spread from them. Thus malignant tumour can be lethal as against the benign tumour.

Question 7.
Prevention is better than cure for AIDS.
Answer:
Till this time, there is no preventive vaccination for AIDS. There is also no cure for AIDS. The medicines are also costly and may not give complete cure. The only way to remain away from AIDS is the complete awareness about it. Thus it should be prevented by not allowing HIV to enter our body. Once HIV finds the entrance, the cure is impossible. Therefore, it is said that prevention is better them cure for AIDS.

Write short notes

Question 1.
Cellular factors in innate immunity.
Answer:

1. Phagocytic cells ingest and destroy the pathogens.
2. This is natural defence against the invasion of pathogenic microorganisms and other foreign particles in blood and tissues.
3. Phagocytic cells are of two types, viz. microphages and macrophages. They can remove foreign particles that enter the body.
4. Natural killer (NK) cells is a class of lymphocytes which carry out important and non-specific defence against viral infections and tumours.

Question 2.
Acute phase proteins (APPs).
Answer:

1. Acute phase proteins are involved in innate immune mechanism.
2. When there is an infection or injury, it leads to a sudden increase in concentration of certain plasma proteins, which are called acute phase proteins or APPs.
3. These include C Reactive Protein (CRP), Mannose binding protein, Alpha-1-acid glycoprotein, Serum Amyloid P etc.
4. APPs enhance host resistance, prevent tissue injury and promote repair of inflammatory lesions.

Question 3.
Rh factor.
Answer:
Rh factor:

1. Rh factor is the term adapted from Rhesus monkey.
2. In rhesus monkey, there is antigen D on the surface of their RBCs.
3. Landsteiner and Wiener discovered this antigen and termed it as Rh factor.
4. Persons having Rh factor or D antigen are called Rh positive while those lacking D antigen or Rh factor are called Rh negative.

Question 4.
Erythroblastosis foetalis.
Answer:

1. Erythroblastosis foetalis is condition in which there is destruction of the erythrocytes of the foetus. It is the haemolytic disease of the newborn (HDN).
2. This is caused in foetus, if mother is Rh -ve and father is Rh +ve. Rh +ve is the dominant allele, the foetus becomes Rh +ve, when its father is RH +ve.
3. Rh +ve blood groups have D antigen which induces a strong immunogenic response when introduced into Rh -ve individuals.
4. During foetal life, there is connection between mother and foetus through placenta, therefore Rh +ve antigen D from the foetus enters maternal circulation.
5. This triggers formation of anti-Rh antibodies in mother. Subsequently Rh+ve foetus receives anti-Rh antibodies produced by mother.
6. This causes agglutination reaction resulting into haemolysis in foetus. In order to prevent HDN, Rh -ve mother is injected with the anti-Rh antibody during all her pregnancies if her husband is Rh +ve.

Question 5.
Common cold.
Answer:

1. The common cold (nasopharyngitis or rhinopharyngitis) is a viral infectious disease of the upper respiratory system. The causative organisms are rhinoviruses and coronaviruses.
2. Symptoms include cough, sore throat, runny nose and fever.
3. There is no known treatment, however, symptoms usually resolve spontaneously in 7 to 10 days.
4. The best prevention for the common cold is to stay away from infected people and places where infected individuals have been.
5. Hand washing with plain soap and water is recommended. Also alcohol-based hand sanitizers provide very little protection.

Question 6.
Life cycle of Plasmodium.
Answer:

1. Anopheles Female mosquito which is a carrier carries sporozoites. When it bites the human, these sporozoites enter human circulation.
2. Sporozoites undergo asexual reproduction through fission or schizogony in the liver cells or erythrocytes of the human.
3. It forms merozoites. The cells formed within erythrocytes function as gametocytes. They undergo gamogony.
4. Upon biting such person, the gametocytes enter into female Anopheles, fertilization occurs in its gut.
5. Diploid zygote transforms into oocyst. Oocyst forms large number of haploid sporozoites through meiosis (sporogony).
6. Sporozoites migrate to salivary glands and are ready to infect new human host.
7. Again Sporozoite → Merozoite → Trophozoite → Schizont sequence is carried on for plasmodial stages in human body.
8. The sexual life cycle of Plasmodium occurs in mosquito body which acts as a vector. While its asexual phase takes place in human body.

Question 7.
Pneumonia.
Answer:

1. Pneumonia is an inflammatory condition of alveoli in the lungs causing formation of fluid in the lungs. This condition is called consolidation and exudation.
2. Causes of pneumonia are infection due to bacteria, viruses, fungi or parasites, chemical burns or physical injury to the lungs.
3. Influenza virus, adenovirus, para influenza and Respiratory Syncytial Virus (RSV) are some viruses that can cause pneumonia. Bacteria like Streptococcus pneumoniae and fungal pathogens e.g. Pneumocystis jirovecii and Pneumocystis carinii can also spread infection of pneumonia. Chemical burns of physical injury to lungs also cause similar infection.
4. Main symptoms of infectious pneumonia are cough producing greenish or yellow sputum or phlegm and a high fever with chills.
5. Shortness of breath or dyspnea, stabbing chest pain, coughing up blood, headaches, sweaty and clammy skin, loss of appetite, fatigue, blueness of the skin, nausea, vomiting, mood swings and joint pains or muscle aches are some other symptoms.
6. Preventive vaccination against pneumonia is available. Medicines such as Benzyl penicillin, Ampicillin and Chloramphenicol are effective to prevent pneumonia.

Question 8.
Ringworm.
Answer:

1. Ringworm or Dermatophytosis is a clinical condition caused by Trichophyton and Microsporum fungal infection of the skin. This infection is seen in humans and pets.
2. Dermatophytes are the fungi that feed on keratin. Keratin is the material found in the outer layer of skin, hair and nails.
3. These fungi attack various parts of the body. Infections on the body forms enlarged raised red rings. These patches have intense itching. Infection on the skin of the feet may cause athlete’s foot and jock itch.
4. When the nails are infected it causes onychomycosis. During this the nails thicken, discolour and finally crumble and fall off.
5. Prevention of ringworm infection is to be done by avoiding sharing of clothing, sports equipment, towels or sheets. Clothes should be washed in hot water with fungicidal soap after suspected exposure to ringworm. One should not walk barefoot but use appropriate footwear.
6. Diagnosis of ringworm is done by physical examination and treatment is done with uses drugs like nystatin, fluconazole, itraconazole, etc.

Question 9.
Dengue.
Answer:

1. Dengue is a viral disease causing high fever. It is a painful, debilitating vector-borne disease.
2. There are four closely related dengue viruses that cause infection.
3. Vector of Dengue virus is female Aedes mosquito. The mosquito takes up the dengue virus when it sucks blood of a person suffering from dengue.
4. The spread of dengue is not directly from one person to another person.

Question 10.
Performance enhancers.
Answer:

1. Performance enhancers are certain drugs used by sportspersons to enhance their performance during competitions.
2. Narcotic analgesics, anabolic steroids, diuretics and certain hormones are misused by such sportspersons to increase muscle strength and bulk. It also promotes aggressiveness and improve overall performance.
3. Use of anabolic steroids cause side effects.
4. Females show masculinization, increased aggressiveness, mood swings, depression, abnormal menstrual cycles, excessive hair growth on the face and body, enlargement of clitoris, deepening of voice.
5. Males show acne, increased aggressiveness, mood swings, depression, and reduction of size of the testicles, decreased sperm production, kidney and liver dysfunction, breast enlargement, premature baldness, enlargement of the prostate gland.
6. These effects may be permanent with prolonged use. Using such drugs is illegal and punishable.

Chart Based Questions

Question 1.
Complete the chart of ABO blood group system and answer the questions given below:

Questions:
(i) Which blood group from the above table is called universal acceptor?
(ii) Which blood group from the above table is called universal donor?
Answer:

(i) Blood group AB is called universal acceptor.
(ii) Blood group O is called universal donor.

Question 2.
Complete the table

Answer:

Question 3.
Complete the following table

Answer:

Question 4.
Complete the following table:

Answer:

Diagram Based Questions

Question 1.
Label the given diagram
Img 7
Answer:

1. Antigen binding site.
2. Variable region of heavy chain
3. Varible region of light chain
4. Constant region of light chain
5. Constant region of heavy chain
6. Disulphide bond
7. Hinge
8. Light chain
9. Heavy chain

Question 2.
Observe the given diagram and answer the following questions:

(1) What is I and II in the above diagram?
Answer:
I is a virus which is trying to cause infection, II are two antigen molecules which are trying to attack the virus.

(2) What structures are responsible for antigen and antibody complex? Identify them in the above diagram.
Answer:
(a) is epitope which is antigen determinant and
(b) is a paratope which is part of the antibody. Epitope and paratope are specific to each other and hence they form a complex.

(3) What is the study of antigen-antibody interactions called?
Answer:
The study of antigen-antibody interactions is called serology.

Question 3.
Fill in the blanks after observing the diagram.

On the right side of the diagram, the stages of plasmodium are passed in the body of ……………….. Whereas on the left side of the diagram, those take place in the body of ………………, ………………. is the stage that is dormant in the liver of human host. From this ………………… and then ………………… is the stage in the erythrocytes, which rupture and gives rise to …………….. Microgamete and macrogamete fuse with each other to form …………………… which later gives rise to ookinete which forms ………………… This enters the salivary glands of mosquito …………………. phase of Plasmodium occurs in mosquito body, whereas …………………… phase is in human body.
Answer:
On the right side of the diagram, the stages of plasmodium are passed in the body of human. Whereas on the left side of the diagram, those take place in the body of mosquito. Hypnozoite is the stage that is dormant in the liver of human host. From this schizont and then merozoites Trophozoite is the stage in the erythrocytes, which rupture and gives rise to gamerocyte. Microgamete and macrogamete fuse with each other to form zygote which later gives rise to ookinete which forms sporozoites. This enters the salivary glands of mosquito. Sexual phase of Plasmodium occurs in mosquito body, whereas asexual phase is in human body.

Question 4.
Observe the given diagram and answer the following questions

(1) Enlist the stages of Entamoeba histolytica you see in the above diagram.
Answer:
Trophozoite, pre-cystic form, cyst, binucleate cyst, quadrinucleate cyst, Metacycstic amoeba, amoebulae are the different stage of Entamoeba histolytica that are seen in the above diagram.

(2) Where are these stages passed?
Answer:
These stages are passed in the lumen of intestine of the host human being.

(3) How does Entamoeba come out of the body of the host?
Answer:
Encysted Entamoeba pass out with the faecal matter of the host.

Question 5.
Observe the given diagram and answer the following questions:

(1) In life cycle of Ascaris at what stage do they enter the human body?
Answer:
When there is development of infective larva inside the egg of Ascaris, it enters the human body.

(2) How do they enter the human body and through which organ do they enter?
Answer:
Ascaris eggs are deposited in the faeces. They mix in the soil, if faeces is exposed in open. From there, it can enter into nearby water body or it may contaminate vegetables or other food stuffs. Such unhygienic food or unclean hands pass these eggs in the body of human through the mouth.

(3) What are the vital organs affected by the Ascaris during its development within the body of host human ?
Answer:
Ascaris can affect trachea, lungs, heart, brain and eyes too.

(4) In which organ do they copulate and produce fertilized eggs?
Answer:
Adult male and female copulate in the intestine of the host human.

Question 6.
Observe the given diagram and answer the following questions:

(1) In which host stage II is completed?
Answer:
Stage II is completed in human.

(2) What happens in step 1 and step 2?
Answer:
Humans are infected at step 1 when mosquito bites human and larvae enter blood stream. In step 2 adult Wuchereria worms are formed in lymphatics.

(3) Describe the events in step 3.
Answer:
Mosquito carries the blood as it bites the human in step 4 and ingests microfilariae in human blood. Later the microfilariae start growing in the midgut of mosquito.

(4) In which host stage I is completed?
Answer:
Stage I is completed in mosquito.

Question 7.
Sketch and label the diagram of pathogen that causes typhoid.
Answer:
Pathogen of typhoid is Salmonella typhi.

Question 8.
Sketch and label disease causing agents of pneumonia.
Answer:

Question 9.
Sketch and label benign and malignant tumours.
Answer:

Question 10.
Sketch and label structure of HIV.
Answer:

Long answer questions

Question 1.
Describe different ways in which epithelial surface offers the innate immunity.
Answer:

1. Skin and mucous covering, when intact protects the body against the invasion by pathogens. The healthy skin has bactericidal activity due to the salts present in drying sweat.
2. Sebaceous glands in the skin produce secretions and long chain of fatty acids. These are bactericidal and fungicidal.
3. Respiratory tract is provided with mucosa which prevents entry of microorganisms to a large extent.
4. The inhaled particles are arrested through hair in the nasal passage. The particles that pass beyond nasal passage are caught by mucus lining the epithelium. They are swept back to pharynx. Then they are either swallowed or coughed out.
5. The cough reflex is an important defence mechanism of respiratory tract.
6. There is saliva in the mouth which has inhibitory effect on microorganisms. Gastric secretions has acidity and hence microorganisms are destroyed in stomach.
7. The flushing action of urine eliminates bacteria from the urethra. Semen too has antibacterial substances, e.g. Spermine and zinc.

Question 2.
Explain ABO blood group system in human being with a suitable chart.
Answer:

1. In ABO system, the blood groups are determined by the antigen present on the surface of red blood cells.
2. The blood groups are of four types, viz. A. B, AB and O.
3. In person with blood group A there is antigen ‘A’ on the surface of their red blood cells (RBCs) and antibodies ‘b’ in their plasma.
4. In person with blood group B there is antigen ‘B’ on the surface of their red blood cells (RBCs) and antibodies ‘a’ in their plasma.
5. In person with blood group AB there are both antigens ‘A’ and ‘B’ on the surface of their RBCs and no antibodies in their plasma.
6. In person with blood group ‘O’ there are no antigens ‘A’ and ‘B’ on the surface of their RBCs but have both ‘a’ and ‘b’ antibodies in their plasma.
7. During blood transfusion compatibility of blood has to be taken into consideration.
8. Person with ‘O’ blood group is called universal donor while the person with ‘AB’ blood group is called universal recipient. Individuals with blood group O can donate blood to anyone, while those individuals with blood group AB can receive blood from any person.
   

Question 3.
What are the main causes of cancer?
Answer:
Causes of Cancer : Following carcinogenic factors are responsible for causing cancer.

1. Chemicals : Many induce development of cancer. E.g. nicotine, caffeine, polycyclic hydrocarbons and products of combustion of coal and oil. Sex hormone and steroids, if given or secreted in excess, can cause cancer. E.g. Breast cancer.
2. Radiation : Radiations such as X-rays, gamma-rays, cosmic rays, ultra-violet rays are carcinogenic.
3. Viruses : Virus possessing oncogenes (v-onc genes) are carcinogenic. E.g. EBV (Epstein-barr virus), HPV (Human papiloma virus) are oncogenic viruses.
4. Oncogenes : Cellular oncogenes (c-onc genes) or proto-oncogenes can cause cancer. They are present in normal cells but if activated they lead to oncogenic transformation of cells.
5. Addiction : Addictive substances like cigarette smoke, tobacco lead to cancer of mouth, lips and lungs. Alcohol can cause cancer of oesophagus, stomach, intestine and liver. Drugs like marijuana or anaerobic steroids can also cause cancer.

Question 4.
What are the different ways of treating cancer?
Answer:
Cancer treatment consists of combination of a number of therapies which are follows:
(1) Chemotherapy : Chemotherapy means giving certain anticancer drugs. These drugs check cell division by inhibiting DNA synthesis. But these are more toxic to cancerous cell than to normal cells. Chemotherapy shows side effects such as hair loss or anaemia.

(2) Radiotherapy : In addition to chemotherapy, radiations are given. The cancer cells are bombarded with the radiations from radioactive materials such as cobalt, iridium and iodine. The X-rays, gamma rays and charge particles are used to destroy the cancerous tissue or cells. They cause minimum damage to the surrounding normal tissue or cells.

(3) Surgery : Entire cancerous tissue or cells are removed surgically. E.g. breast tumour or uterine tumour. After removing the cancerous tissue, additionally other treatments are also given.

(4) Immunotherapy : For tackling with tumour, patients are given biological response modifiers such as a-interferon which activates their immune system to destroy the tumour.

(5) Supportive therapy : With supportive therapy, patient’s quality of life is increased. To treat symptoms of cancer and side effects of cancer treatments, this therapy is used. This therapy varies depending upon condition of individual patient.

Balbharti Maharashtra State Board 12th Biology Important Questions Chapter 9 Control and Co-ordination Important Questions and Answers.

Maharashtra State Board 12th Biology Important Questions Chapter 9 Control and Co-ordination

Multiple choice questions

Question 1.
The supporting cells that produce myelin sheath in the CNS are ……………….
(a) Oligodendrocytes
(b) Satellite cells
(c) Astrocytes
(d) Schwann cells
Answer:
(a) Oligodendrocytes

Question 2.
Human brain develops to its full size at an age of year/s.
(a) 1
(b) 6
(c) 12
(d) 18
Answer:
(b) 6

Question 3.
Telencephalon is the other name of ……………….
(a) pons varolii
(b) medulla oblongata
(c) cerebrum
(d) cerebellum
Answer:
(c) cerebrum

Question 4.
Olfactory tracts merge in olfactory area of lobe.
(a) Frontal
(b) Parietal
(c) Occipital
(d) Temporal
Answer:
(d) Temporal

Question 5.
………………. is the largest commissure of the human brain.
(a) Corpora striata
(b) Corpora quadrigemina
(c) Habencular commissure
(d) Corpus callosum
Answer:
(d) Corpus callosum

Question 6.
Grey matter of the brain shows large collection of ……………….
(a) dendrons
(b) cytons
(c) axons
(d) synapsis
Answer:
(b) cytons

Question 7.
Masses of grey matter in white matter of the cerebrum are called ……………….
(a) corpora striata
(b) corpus callosum
(c) paracoel
(d) basal ganglia
Answer:
(d) basal ganglia

Question 8.
Parietal and temporal lobes of cerebrum are separated by sulcus.
(a) lateral
(b) parieto occipital
(c) central
(d) median longitudinal
Answer:
(a) lateral

Question 9.
……………… area is motor speech area
(a) Acoustic
(b) Wernike’s
(c) Somato sensory
(d) Broca’s
Answer:
(d) Broca’s

Question 10.
Maxillary nerve is a branch of nerve.
(a) Occulomotor
(b) Trochlear
(c) Trigeminal
(d) Facial
Answer:
(c) Trigeminal

Question 11.
Spinal accessory is the cranial nerve.
(a) IV
(b) VI
(c) IX
(d) XI
Answer:
(d) XI

Question 12.
Rotation of eye ball is controlled by ……………….
(a) Optic nerve
(b) Pathetic nerve
(c) Auditory nerve
(d) Hypoglossal nerve
Answer:
(b) Pathetic nerve

Question 13.
The spinal nerves emerge out of vertebral column through ……………….
(a) intervertebral foramina
(b) neural canal
(c) central canal
(d) foramen magnum
Answer:
(a) intervertebral foramina

Question 14.
The neuro transmitter is removed by an enzyme called ……………….
(a) noradrenaline
(b) acetylcholine
(c) hyaluronidase
(d) cholinesterase
Answer:
(d) cholinesterase

Question 15.
The reflex action originates in ……………….
(a) sensory neuron
(b) motor neuron
(c) receptor organ
(d) effector organ
Answer:
(c) receptor organ

Question 16.
Cytons of neurons are located in dorsal root ganglion.
(a) afferent
(b) efferent
(c) adjustor
(d) association
Answer:
(a) afferent

Question 17.
Wall of carotid arteries contain ……………….
(a) thermoreceptors
(b) mechanoreceptors
(c) baroreceptors
(d) statoacoustic receptors
Answer:
(c) baroreceptors

Question 18.
The electronegativity inside the membrane is due to ……………….
(a) less anions than cations
(b) less cations than anions
(c) bicarbonates
(d) carbonates
Answer:
(b) less cations than anions

Question 19.
The neuro transmitters stimulate ……………….
(a) presynaptic membrane
(b) cyton
(c) axon terminals
(d) postsynaptic membrane
Answer:
(d) postsynaptic membrane

Question 20.
………………. is an extero-receptor.
(a) Thermoreceptor
(b) Baroreceptor
(c) Proprioreceptor
(d) Enteroreceptor
Answer:
(a) Thermoreceptor

Question 21.
The are described as windows for brain.
(a) sensory neurons
(b) motor neurons
(c) effectors
(d) sense organs
Answer:
(d) sense organs

Question 22.
Otolith organ is formed of ……………….
(a) cochlea and vestibule
(b) sacculus and utriculus
(c) semicircular canals
(d) ear ossicles
Answer:
(b) sacculus and utriculus

Question 23.
Olfactory bulbs are extensions of brain’s ……………….
(a) cerebrum
(b) limbic system
(c) RAS
(d) pons varolii
Answer:
(b) limbic system

Question 24.
Gustatory senses are noted by ……………….
(a) retina
(b) skin
(c) nose
(d) tongue
Answer:
(d) tongue

Question 25.
………………. is attached to the eardrum.
(a) Malleus
(b) Incus
(c) Stapes
(d) Cochlea
Answer:
(a) Malleus

Question 26.
Eustachian tube is present in ……………….
(a) external ear
(b) internal ear
(c) heart
(d) middle ear
Answer:
(d) middle ear

Question 27.
The internal ear is a fluid filled structure called ……………….
(a) cochlea
(b) vestibule
(c) labyrinth
(d) otolith
Answer:
(c) labyrinth

Question 28.
The space within cochlea is known as ……………….
(a) scala vestibule
(b) scala tympani
(c) aqueous chamber
(d) scala media
Answer:
(d) scala media

Question 29.
Thermoregulatory centre in the body is ……………….
(a) hypothalamus
(b) cerebellum
(c) spinal cord
(d) pituitary
Answer:
(a) hypothalamus

Question 30.
Which of the following is a sensory nerve?
(a) Vagus
(b) Auditory
(c) Facial
(d) Lumbar
Answer:
(b) Auditory

Question 31.
Chemical transmission in synapse occurs due to ……………….
(a) cholesterol
(b) ADH
(c) acetylcholine
(d) cholinesterase
Answer:
(c) acetylcholine

Question 32.
Voluntary muscular coordination is under the control of ……………….
(a) medulla
(b) pons
(c) hypothalamus
(d) cerebrum
Answer:
(d) cerebrum

Question 33.
All involuntary vital activities are under the control of ……………….
(a) medulla oblongata
(b) cerebellum
(c) cerebral hemispheres
(d) pons Varolii
Answer:
(a) medulla oblongata

Question 34.
Cerebellum is controlling centre for ……………….
(a) muscular strength
(b) memory
(c) equilibrium
(d) muscular coordination
Answer:
(c) equilibrium

Question 35.
Which receptors are present in the retina?
(a) Chemoreceptors
(b) Thermoreceptors
(c) Photoreceptors
(d) Baroreceptors
Answer:
(c) Photoreceptors

Question 36.
Breathing is controlled by ……………….
(a) trachea
(b) medulla oblongata
(c) lungs
(d) hypothalamus
Answer:
(b) medulla oblongata

Question 37.
Corpus callosum is a nerve fibre bridge which connects ……………….
(a) two cerebral hemispheres
(b) cerebrum and cerebellum
(c) cerebellum and medulla
(d) midbrain and hindbrain
Answer:
(a) two cerebral hemispheres

Question 38.
Centre for thirst and hunger are located in ……………….
(a) cerebrum
(b) cerebellum
(c) hypothalamus
(d) medulla
Answer:
(c) hypothalamus

Question 39.
Gyri in the brain are present in ……………….
(a) cerebral cortex
(b) olfactory lobes
(c) medulla oblongata
(d) hypothalamus
Answer:
(a) cerebral cortex

Question 40.
Which of the following is a structure of mesencephalon?
(a) Inferior colliculi
(b) Thalamus
(c) Cerebellum
(d) Pons varolii
Answer:
(a) Inferior colliculi

Question 41.
Third ventricle lies in ……………….
(a) midbrain
(b) forebrain
(c) cerebellum
(d) medulla oblongata
Answer:
(b) forebrain

Question 42.
Medulla oblongata encloses ……………….
(a) third ventricle
(b) fourth ventricle
(c) first ventricle
(d) second ventricle
Answer:
(b) fourth ventricle

Question 43.
Loss of memory may result from injury to the ……………….
(a) corpora quadrigemina
(b) pons varolii
(c) cerebellum
(d) cerebrum
Answer:
(d) cerebrum

Question 44.
Terminal non-nervous part of spinal cord is ……………….
(a) funiculus
(b) filum terminale
(c) cauda equina
(d) conus terminalis
Answer:
(b) filum terminale

Question 45.
Which part of the pituitary is neurohaemal organ?
(a) Pars distalis
(b) Infundibulum
(c) Pars nervosa
(d) Pars intermedia
Answer:
(c) Pars nervosa

Question 46.
Development of secondary sexual characteristics in female is under the control of ……………….
(a) growth hormone
(b) TSH
(c) estrogen
(d) progesterone
Answer:
(c) estrogen

Question 47.
Hypersecretion of STH in children causes ……………….
(a) cretinism
(b) gigantism
(c) dwarfism
(d) myxoedema
Answer:
(b) gigantism

Question 48.
Milk secretion in lactating woman is controlled by ……………….
(a) LH
(b) prolactin
(c) relaxin
(d) oestrogen
Answer:
(b) prolactin

Question 49.
ADH is secreted by
(a) adrenal gland
(b) thyroid
(c) hypothalamus
(d) pancreas
Answer:
(c) hypothalamus

Question 50.
BMR is increased by the administration of ……………….
(a) insulin
(b) GH
(c) thyroxine
(d) testosterone
Answer:
(c) thyroxine

Question 51.
The largest endocrine gland in the body is ……………….
(a) pituitary
(b) adrenal
(c) liver
(d) thyroid
Answer:
(d) thyroid

Question 52.
Diabetes insipidus is caused by the deficiency of ……………….
(a) calcitonin
(b) oxytocin
(c) atrial natriuretic factor
(d) vasopressin
Answer:
(d) vasopressin

Question 53.
Simple goitre is caused by the deficiency of ……………….
(a) TSH
(b) thyrocalcitonin
(c) thyroxine
(d) iodine
Answer:
(d) iodine

Question 54.
Exopthalmic goitre is also known as ……………….
(a) Grave’s disease
(b) Gull’s disease
(c) Simple goitre
(d) Cushing’s disease
Answer:
(a) Grave’s disease

Question 55.
Cushing’s syndrome is developed due to ……………….
(a) hyposecretion of ACTH
(b) hypersecretion of corticoids
(c) hyposecretion of thyroxine
(d) hypersecretion of thyroxine
Answer:
(b) hypersecretion of corticoids

Question 56.
Pituitary gland is under the control of ……………….
(a) thyroid
(b) adrenal
(c) pineal
(d) hypothalamus
Answer:
(d) hypothalamus

Question 57.
FSH is secreted by ……………….
(a) pituitary gland
(b) thyroid gland
(c) ovary
(d) adrenal gland
Answer:
(a) pituitary gland

Question 58.
ICSH stimulates ……………….
(a) ovary
(b) Leydig cells
(c) seminiferous tubules
(d) kidney
Answer:
(b) Leydig cells

Question 59.
Which of the following secrete LH ?
(a) Pituitary
(b) Thyroid
(c) Ovary
(d) Adrenal
Answer:
(a) pituitary

Question 60.
TSH regulates secretion.
(a) thyroxine
(b) MSH
(c) androgens
(d) insulin
Answer:
(a) thyroxine

Question 61.
Deficiency of thyroxine in adults cause ……………….
(a) cretinism
(b) myxoedema
(c) diabetes
(d) Cushing’s disease
Answer:
(b) myxoedema

Question 62.
Osmotic pressure and blood pressure are maintained by ……………….
(a) glucocorticoids
(b) aldosterone
(c) TRF
(d) MSH
Answer:
(b) aldosterone

Question 63.
Hormone secreted by corpus luteum is ……………….
(a) aldosterone
(b) progesterone
(c) testosterone
(d) cortisol
Answer:
(b) progesterone

Question 64.
………………. is also called hypophyseal stalk.
(a) Infundibulum
(b) Median eminence
(c) Pars intermedia
(d) Sphenoid bone
Answer:
(a) infundibulum

Question 65.
………………. is like a collar around hypophyseal stalk.
(a) Pars distalis
(b) Pars nervosa
(c) Pars intermedia
(d) Pars tuberalis
Answer:
(d) Pars tuberalis

Question 66.
Herring bodies are the parts of ……………….
(a) hypothalamo-hypophyseal tracts
(b) pituicytes
(c) hypothalamo-hypophyseal portal system
(d) pituitary cleft
Answer:
(a) hypothalamo-hypophyseal tracts

Question 67.
Corticotropin is the other name of ……………….
(a) ACTH
(b) STH
(c) Aldosterone
(d) ADH
Answer:
(a) ACTH

Question 68.
Adrenal failure leads to ……………….
(a) Acromegaly
(b) Simmond’s disease
(c) Midget
(d) Addison’s disease
Answer:
(d) Addison’s disease

Question 69.
Prolactin inhibiting factor is secreted by ……………….
(a) Hypophysis
(b) Hypothalamus
(c) Thyroid
(d) Mammary glands
Answer:
(b) Hypothalamus

Question 70.
Which one of the following is not applicable to prolactin ?
(a) Mammotropin
(b) Lactogenic hormone
(c) Somatotropin
(d) Luteotropin
Answer:
(c) Somatotropin

Question 71.
………………. is a gonadotropic hormone.
(a) STH
(b) LTH
(c) ACTH
(d) FSH
Answer:
(d) FSH

Question 72.
Rhythmic integrated contractions of jejunum are controlled by ……………….
(a) coherin
(b) insulin
(c) glucagon
(d) ADH
Answer:
(a) coherin

Question 73.
Thyroid gland is derived from of embryo.
(a) ectoderm
(b) mesoderm
(c) endoderm
(d) ecto-endoderm
Answer:
(c) endoderm

Question 74.
Deficiency of thyroxine in infants causes ……………….
(a) Cretinism
(b) Grave’s disease
(c) Myxoedema
(d) Exophthalmos
Answer:
(a) Cretinism .

Question 75.
………………. is a hypercalcemic hormone.
(a) PTH
(b) TCT
(c) Thyroxine
(d) ACTH
Answer:
(a) PTH

Question 76.
………………. is a middle layer of adrenal cortex.
(a) Zona fasciculata
(b) Zona pellicida
(c) Zona glomerulosa
(d) Zona reticularis
Answer:
(a) Zona fasciculata

Question 77.
Decrease in the blood calcium level is ……………….
(a) hyperglycemia
(b) hypercalcemia
(c) hypoglycemia
(d) hypocalcemia
Answer:
(d) hypocalcemia

Question 78.
………………. stimulates RBC production.
(a) Aldosterone
(b) Cortisol
(c) Epinephrine
(d) Parathormone
Answer:
(b) Cortisol

Question 79.
Chemicals which are released at the synaptic junction are called ……………….
(a) hormones
(b) neurotransmitters
(c) cerebrospinal fluid
(d) lymph
Answer:
(b) neurotransmitters

Question 80.
Potential difference across resting membrane is negatively charged. This is due to differential distribution of the following ions.
(a) Na⁺ and K⁺ ions
(b) Ca⁺⁺ and Cl^– ions
(c) Ca⁺⁺ and Mg⁺⁺ ions
(d) Mg⁺⁺ and Cl^– ions
Answer:
(a) Na⁺ and K⁺ ions

Question 81.
Which of the following is not involved in Knee-jerk reflex?
(a) Muscle spindle
(b) Motor neuron
(c) Brain
(d) Inter neurons
Answer:
(c) Brain

Question 82.
An area in the brain which is associated with strong emotions is ……………….
(a) Cerebral cortex
(b) Cerebellum
(c) Limbic system
(d) Medulla
Answer:
(c) Limbic system

Question 83.
Which is the vitamin present in Rhodopsin?
(a) Vitamin A
(b) Vitamin B
(c) Vitamin C
(d) Vitamin D
Answer:
(a) Vitamin A

Question 84.
Wax gland present in the ear canal is modified ……………….
(a) Sweat gland
(b) Vestibular gland
(c) Cowper’s gland
(d) Sebaceous gland
Answer:
(d) Sebaceous gland

Question 85.
The part of internal ear responsible for hearing is ……………….
(a) cochlea
(b) semicircular canal
(c) utriculus
(d) sacculus
Answer:
(a) cochlea

Question 86.
The organ of corti is a structure present in ……………….
(a) external ear
(b) middle ear
(c) semi circular canal
(d) cochlea
Answer:
(d) cochlea

Question 87.
Select the right match of endocrine gland and their hormones among the options given below.
A. Pineal i. Epinephrine
B. Thyroid ii. Melatonin
C. Ovary iii. Estrogen
D. Adrenal medulla iv. Tetraiodothyronine
(a) A-iv, B-ii, C-iii, D-i
(b) A-ii, B-iv, C-i, D-iii
(c) A-iv, B-ii, C-i, D-iii
(d) A-ii, B-iv, C-iii, D-i
Answer:
(d) A-ii, B-iv, C-iii, D-i

Question 88.
Listed below are the hormones of anterior pituitary origin. Tick the wrong entry.
(a) Growth hormone
(b) FSH
(c) Oxytocin
(d) ACTH
Answer:
(c) Oxytocin

Question 89.
Mary is about to face an interview. But during the first five minutes before the interview she experiences sweating, increased rate of heartbeat, respiration, etc. Which hormone is responsible for her restlessness?
(a) Estrogen and progesterone
(b) Oxytocin and vasopressin
(c) Adrenaline and noradrenaline
(d) Insulin and glucagon
Answer:
(c) Adrenaline and noradrenaline

Question 90.
The steroid responsible for balance of water and electrolytes in our body is ……………….
(a) Insulin
(b) Melatonin
(c) Testosterone
(d) Aldosterone
Answer:
(d) Aldosterone

Question 91.
Thymosin is responsible for ……………….
(a) raising the blood sugar level
(b) raising the blood calcium level
(c) increased production of T lymphocytes
(d) decrease in blood RBC
Answer:
(c) increased production of T lymphocytes

Question 92.
In the mechanism of action of a protein hormone, one of the second messengers is ……………….
(a) Cyclic AMP
(b) Insulin
(c) T₃
(d) Gastrin
Answer:
(a) Cyclic AMP

Question 93.
Leydig cells produce a group of hormones called ……………….
(a) androgens
(b) estrogen
(c) aldosterone
(d) gonadotropins
Answer:
(a) androgens

Question 94.
Corpus luteum secretes a hormone called ……………….
(a) prolactin
(b) progesterone
(c) aldosterone
(d) testosterone
Answer:
(b) progesterone

Question 95.
Cortisol is secreted from ……………….
(a) pancreas
(b) thyroid
(c) adrenal
(d) thymus
Answer:
(c) adrenal

Question 96.
A hormone responsible for normal sleep – wake cycle is ……………….
(a) epinephrine
(b) gastrin
(c) melatonin
(d) insulin
Answer:
(c) melatonin

Question 97.
Match the pairs and choose the correct answer among the following options.
A. Epinephrine
i. Increase in muscle growth
B. Testosterone
ii. Decrease in blood pressure
C. Glucagon
iii. Decrease in liver glycogen content
D. Atrial natriuretic factor
iv. Increase in heartbeat
(a) A-ii, B-i, C-iii, D-iv
(b) A-iv, B-i, C-iii, D-ii
(c) A-i, B-ii, C-iii, D-iv
(d) A-i, B-iv, C-ii, D-iii
Answer:
(b) A-iv, B-i, C-iii, D-ii

Question 98.
Blood calcium level is a resultant of how much dietary calcium is absorbed, how much calcium is lost in the urine, how much bone dissolves releasing calcium into the blood and how much calcium from blood enters tissues. Several factors play an important role in these processes. Mark the one which has no role.
(a) Vitamin D
(b) Parathyroid hormone
(c) Thyrocalcitonin
(d) Thymosin
Answer:
(d) Thymosin

Question 99.
All the following tissues in mammals except one consists of a central ‘medullary’ region surrounded by a cortical region. Mark the wrong entry.
(a) Ovary
(b) Adrenal
(c) Liver
(d) Kidney
Answer:
(c) Liver

Match the columns

Question 1.
Match the hormones with their source

Answer:

Question 2.
Match the layer of adrenal with its hormone.

Answer:

Question 3.
Match the disorder with the gland associated with it.

Answer:

Classify the following to form Column B as per the category given in Column A

Question 1.

Answer:

Question 2.
Types of nerves
Occulomotor, Facial, Optic, Vagus, Abducens, Vestibulocochlear

Answer:

Question 3.
Hormones
Estrogen, Glucagon, Epinephrine, Relaxin, Somatostatin, Nor-Adrenalin

Answer:

Question 4.
Disorders
Dwarfism, Myxoedema, Addison’s disease, Cushing’s disease, Gigantism, Goitre

Answer:

Very short answer questions

Question 1.
What is the need for the control and coordination in multicellular animals?
Answer:
Multicellular animals need control and coordination to maintain constancy of internal environment, i.e. homeostasis.

Question 2.
How do plants carry out control and coordination?
Answer:
Plants carry out control and coordination by sending chemical signals and bringing about various types of movements.

Question 3.
What is the type of nervous system of Earthworm?
Answer:
Earthworm is an annelid having ventral, ganglionated nervous system. It consists mainly of nerve ring, nerve cord and peripheral segmentally arranged nerves.

Question 4.
What kind of nervous system is seen in Hydra, earthworm and cockroach?
Answer:
In Hydra, the nervous system is in the form of nerve net, while in earthworm and cockroach the nervous system is ganglionated.

Question 5.
What is a gland?
Answer:
An organized collection of secretory epithelial cells capable of producing of some secretion is called a gland.

Question 6.
What do you mean by discrete endocrine glands ?
Answer:
The glands which are exclusively endocrine in function are discrete endocrine glands.

Question 7.
What is genu and splenium?
Answer:
Genu is anterior and splenium is posterior fold of corpus callosum.

Question 8.
Which is the largest basal nucleus of brain ?
Answer:
Corpus striatum is the largest basal nucleus of the brain.

Question 9.
What is EEG?
Answer:
EEG is electro encephalography. It is used to detect the electrical changes taking place in the brain.

Question 10.
Mention the major sulci present in the cerebral hemispheres.
Answer:
The sulci present in the cerebral hemisphere are – central sulcus, parieto-occipital sulcus and lateral sulcus.

Question 11.
What is the difference in ‘tract’ and ‘nerve’?
Answer:
A bundle of axons within CNS is called a ‘tract’ while the one outside the CNS is called ‘nerve’.

Question 12.
What is a choroid plexus? State its locations.
Answer:
Network of blood capillaries associated with the brain is called choroid plexus, which are anterior choroid plexus present on the roof of epithalamus and posterior choroid plexus located on the roof of medulla oblongata.

Question 13.
What is a synapse ?
Answer:
The interconnection between two neurons or neuron with motor organ is called synapse.

Question 14.
What is a polarised membrane?
Answer:
The cell membrane of a neuron at resting stage is called polarised membrane. In such membrane, the outer side of the cell membrane is more electropositive due to more Na⁺ ions.

Question 15.
What is summation effect?
Answer:
Many weak stimuli given in a quick succession may produce a response due to summation or additive effect of stimuli, which is known as summation effect.

Question 16.
What is synaptic delay?
Answer:
The time required for a nerve impulse to cross a synapse during transmission of a nerve impulse is called synaptic delay, which is about 0.3-0.5 milliseconds.

Question 17.
What is refractory period?
Answer:
The time interval between two consecutive nerve impulses is called refractory period, during which a nerve cannot be stimulated. Nerve is stimulated only after completion of this period.

Question 18.
What is a synaptic cleft?
Answer:
Small intercellular space between two successive neurons which is about 20¬30 nm in width, is called synaptic cleft.

Question 19.
What is synaptic transmission?
Answer:
The process by which the impulse from the pre-synaptic neuron is conducted to the post-synaptic neuron or cell is called synaptic transmission.

Question 20.
What is a pre-synaptic neuron?
Answer:
The neuron carrying an impulse to the synapse is the pre-synaptic neuron.

Question 21.
What is transmission terminal and generator region?
Answer:
The pre-synaptic membrane of a neuron is transmission terminal while the post- synaptic membrane is called generation region.

Question 22.
What is synaptic fatigue?
Answer:
The synaptic fatigue is the time lag or halting of the transmission of nerve impulse, temporarily at synapse due to exhaustion of its neurotransmitter.

Question 23.
What is the width of synaptic cleft?
Answer:
The width of synaptic cleft is about 20-30 nm.

Question 24.
How much is the resting potential of axon?
Answer:
The resting potential of axon is -70 mV.

Question 25.
How does Na⁺ – K⁺ pump work?
Answer:
During repolarisation of certain part of a nerve, Na⁺ – K⁺ Pump, pumps out 3 Na⁺ ions for every 2 K⁺ ions they pump into the cell.

Question 26.
What is blood-brain barrier?
Answer:
The barrier that keeps a check on passage of ions and large molecules from the blood to the brain tissue is called blood-brain barrier. Endothelial cells lining the blood capillaries help in this process along with the astrocytes.

Question 27.
Enlist meninges of human brain.
Answer:
Dura mater, arachnoid mater or membrane and pia mater are the meninges of human brain.

Question 28.
What is the source of CSF?
Answer:
CSF is secreted by the choroid plexuses of brain and ependymal cells lining the ventricles of brain and central canal of spinal cord.

Question 29.
What is the function of tympanic membrane?
Answer:
Tympanic membrane vibrates on receiving the sound waves and then transfers the vibrations to malleus, the first of the three ear ossicles.

Question 30.
Mention the role of semicircular canals in ear.
Answer:
Semicircular canals help in balancing the equilibrium of the body.

Question 31.
What is the cause for diabetes insipidus?
Answer:
Diabetes insipidus is caused by the deficiency of ADH.

Question 32.
Give role of Parathormone.
Answer:
Parathormone regulates the calcium balance in the body. It increases blood calcium level by increasing reabsorption of calcium from bones.

Question 33.
What is meningitis?
Answer:
Infection of meninges is called meningitis.

Question 34.
Where is general motor area located? What is the function of this area?
Answer:
General motor area is located on precentral gyrus of frontal lobe. It is concerned with all motor activities.

Question 35.
What is the role of Wernicke’s area?
Answer:
Wernicke’s area is the sensory speech area responsible for understanding and formulating written and spoken language.

Question 36.
What is the location of Wernicke’s area?
Answer:
Wernicke’s area is located in the area of contact between temporal, parietal and occipital lobes of cerebrum.

Question 37.
What is the role of Broca’s area?
Answer:
The role of Broca’s area which is the motor speech area that translates thoughts into speech and controls movement of tongue, lips and vocal cords.

Question 38.
What is the location of Broca’s area?
Answer:
Broca’s area is present in the frontal lobe of cerebrum.

Question 39.
Which areas are present in the post central gyrus?
Answer:
General sensory areas concerned with sensation of temperature, touch, pressure, pain and speech are present in the post central gyrus.

Question 40.
Which areas are located on temporal lobe?
Answer:
The areas concerned with sense of taste, sense of hearing and sense of smell are located on temporal lobe.

Question 41.
What is the main function of occipital lobe?
Answer:
Occipital lobe carries sensory visual area which is concerned with the sense of sight. Association visual area is concerned with perception, analysis and storing of information obtained by sight.

Question 42.
What is neuroendocrine system?
Answer:
Neuroendocrine system is an integrated and coordinated system consisting of nervous and endocrine system which brings about the coordination of the body.

Question 43.
What is the quantity of cerebrospinal fluid in adult human being?
Answer:
Cerebrospinal fluid is about 120 ml in adult human being.

Question 44.
How many neurons are present in the brain?
Answer:
There are about 30,000 million neurons in the brain.

Question 45.
Which part of the brain forms 80-85% of the brain?
Answer:
Cerebrum forms 80-85% of the brain.

Question 46.
Which sense is poorly developed in human beings and what is the reason for this?
Answer:
Sense of smell is poorly developed in human beings and it is due to less developed olfactory lobes.

Question 47.
Where are lateral ventricles situated and what is its roof called?
Answer:
Lateral ventricles are the cavities filled with cerebrospinal fluid, present inside the cerebrum and its roof is called pallium.

Question 48.
What is foramen of Monro?
Answer:
Foramen of Monro is a narrow opening that connects lateral ventricle present in cerebrum with third ventricle present in diencephalon.

Question 49.
What is the roof and floor of diencephalon called respectively?
Answer:
Roof of diencephalon is epithalamus and floor of diencephalon is hypothalamus.

Question 50.
Which hormones are produced from pineal gland? Name their functions.
Answer:
Serotonin and melatonin are hormones of pineal gland which are concerned with metabolic activities and regulation of biological rhythm respectively.

Question 51.
What is Habenular commissure?
Answer:
Habenular commissure connects the lateral walls of diencephalon or thalami with each other.

Question 52.
What structure is present on the anterior side of the hypothalamus?
Answer:
Optic chiasma or crossing of two optic nerves is seen on the anterior side of the hypothalamus.

Question 53.
Name the parts of corpora quadrigemina and give their functions.
Answer:
The upper two lobes of corpora quadrigemina are called superior colliculi which receive impulse from optic nerves while the lower two lobes are called inferior colliculi which receive auditory stimuli. Both colliculi control and coordinate head movements.

Question 54.
What is arbour vitae?
Answer:
Arbor vitae is white, branching tree-like processes of white matter that are sent into grey cortex of cerebellum.

Question 55.
Which cranial nerve is called a dentist nerve?
Answer:
Trigeminal, the Vth cranial nerve is called a dentist nerve.

Question 56.
What is central canal?
Answer:
Central canal is the narrow central cavity present inside the spinal cord.

Question 57.
Which cranial nerves originate from the midbrain?
Answer:
Cranial nerves (III) Occulomotor, (IV) Pathetic and (VI) Abducens originate from the midbrain.

Question 58.
What is the other name for the auditory cranial nerve?
Answer:
Vestibulocochlear.

Question 59.
What is the difference between unconditioned and conditioned reflexes?
Answer:
Unconditioned reflexes are inborn or hereditary and permanent while the conditioned reflexes are temporary, learnt or acquired during lifetime.

Question 60.
Give examples of unconditional reflexes.
Answer:
Blinking of eyes, withdrawing of hand upon pricking, suckling to breast by infant, swallowing, knee jerk, sneezing and coughing are some of the unconditional reflexes.

Question 61.
What do you mean by accommodation power of the lens?
Answer:
The ability of the lens by which the light ray from far and near objects is focused on the retina is called accommodation power of the lens. The lens makes fine adjustments to bring such sharp focus on retina.

Question 62.
Where is pituitary located?
Answer:
Pituitary is located inside a depression called sella turcica which is present in sphenoid bone of the skull.

Question 63.
What is the difference between Lorain dwarf and Frohlic dwarf?
Answer:
Lorain dwarf is mentally normal while Frohlic dwarf is mentally abnormal.

Question 64.
How is Simmond’s disease caused?
Answer:
Simmond’s disease is caused due to hyposecretion of GH during adulthood.

Question 65.
How is Addison’s disease caused?
Answer:
Addison’s disease is caused by the hyposecretion of ACTH that leads to adrenal failure.

Question 66.
How is Cushing’s disease caused?
Answer:
Hypersecretion of corticoids causes Cushing’s disease.

Question 67.
What is the main difference between diabetes mellitus and diabetes insipidus?
Answer:
Diabetes mellitus is caused due to deficiency of insulin while diabetes insipidus is caused due to deficiency of ADH.

Question 68.
Which cells secrete coherin? What is the function of coherin?
Answer:
Coherin is the hormone secreted by hypothalamic neurons that brings about prolonged, rhythmic integrated contractions of the jejunum.

Question 69.
What is the difference between Gull’s disease (Myxoedema) and Grave’s disease?
Answer:
Gull’s disease is caused due to hyposecretion of thyroxine while Grave’s disease is caused due to hypersecretion of thyroxine.

Question 70.
In which part thyroid gland stores its hormones?
Answer:
The lumen of thyroid follicles store the thyroid hormones in the form of thyroglobulins.

Question 71.
What are thymosins?
Answer:
Thymosins are hormones secreted by thymus gland which promote the production of antibodies.

Question 72.
Which hormone is secreted by the heart?
Answer:
Heart secretes ANF or Atrial Natriuretic Factor.

Name the following

Question 1.
Name the region consisting of nerve fibres that connects cerebrum and medulla oblongata.
Answer:
Pons Varolii.

Question 2.
Give the names of cranial nerve number VIth and VIIth.
Answer:
VTth cranial nerve is Abducens and Vllth cranial nerve is Facial.

Question 3.
Name the three sulci present on the cerebral hemispheres.
Answer:
Central sulcus, lateral sulcus and parieto¬occipital sulcus.

Question 4.
Name the band of nerve fibres that connect cerebrum, cerebellum and spinal cord.
Answer:
Crura cerebri.

Question 5.
Name the second largest part of the brain.
Answer:
Cerebellum.

Question 6.
Name the three branches of trigeminal nerve.
Answer:
Ophthalmic, Maxillary and Mandibular.

Question 7.
Name the nerve which arises from ventral side of medulla and supplies the tongue.
Answer:
Hypoglossal.

Question 8.
Name of emergency hormones secreted by sympathetic nervous system.
Answer:
Adrenaline and nor-adrenaline are the emergency hormones secreted by sympathetic nervous system.

Question 9.
Name the disorders caused by hyposecretion of thyroxine in children and adults.
Answer:

1. Hyposecretion of thyroxine in children : Cretinism.
2. Hyposecretion of thyroxine in adults : Myoxedema.

Question 10.
Name the dual exocrine as well as endocrine gland. Name the hormones secreted by it.
Answer:
Pancreas is the dual gland, exocrine as well as endocrine, it secretes hormones like insulin, glucagon and somatostatin.

Question 11.
Name the four peptide hormones secreted by endocrine cells of alimentary canal.
Answer:
Gastrin, secretin, cholecystokinin and GIPT or Gastric inhibitory peptide.

Question 12.
Name the disorder caused by the under secretion of thyroxine in children.
Answer:
Cretinism is the disorder seen in children due to under secretion of thyroxine.

Give functions of the following

Question 1.
Meninges and CSF.
Answer:
Functions of meninges:

1. Meninges give protection to the brain and the spinal cord.
2. They are also nutritive in function.
3. Cerebrospinal fluid acts as a shock absorber. It protects the brain from mechanical injuries and from desiccation.
4. It also maintains constant pressure inside and outside the CNS and regulates the temperature.

Functions of CSF:

1. CSF helps in exchange of nutrients and wastes between the blood and the brain tissue.
2. CSF supplies oxygen to the brain.

Question 2.
The functions of forebrain.
Answer:
(A) Functions of cerebrum:

1. The cerebrum controls the voluntary activities.
2. The cerebrum perceives various sensory stimuli received through vision, taste, smell, sound, touch, speech, etc.
3. It is the centre of memory, will-power, intelligence, reasoning and learning.
4. The cerebrum is the centre for emotions, thoughts and feelings, pain, pleasure, fear, fatigue, pressure, temperature, etc.
5. It is also the centre for micturition, defecation, weeping, laughing, etc

(B) Function of olfactory lobes: Sensation of smell.

(C) Functions of diencephalon:

1. Diencephalon acts as a relay centre for motor and sensory impulses between spinal cord, brainstem and various areas of cerebral cortex.
2. Diencephalon consists of epithalamus, thalami and hypothalamus. Therefore it acts as a centre for homeostasis and higher centre of autonomous nervous system.
3. Hypothalamic nuclei secrete neurohormones which influence the pituitary gland.
4. Diencephalon regulates heartbeats, blood pressure and water balance.
5. Anterior choroid plexus which is located in the diencephalon secretes cerebrospinal fluid.
6. Hypothalmic regions control many involuntary functions such as hunger, thirst, thermo-regulation, fear, anger, sleep, sexual desire, etc.

Question 3.
Write various functions of hindbrain.
Answer:
Functions of hindbrain:
(i) Cerebellum:

1. Cerebellum is a primary centre for the control of equilibrium, posture, balancing and orientation.
2. Neuromuscular activities are regulated by the cerebellum.
3. Coordination of walking, running, speaking, etc. is under the control of hindbrain.

(ii) Pons:

1. Activities of two cerebellar hemispheres are coordinated by pons.
2. Nerve fibres cross over in this area and thus the right side of the brain controls the left part of the body and vice versa.
3. Pons controls the consciousness of the brain.
4. Breathing centre is located in pons along with medulla.

(iii) Medulla oblongata:

1. Medulla oblongata controls all the involuntary activities such as heartbeats, respiration, vasomotor activities.
2. Peristalsis and reflex actions such as coughing, sneezing, swallowing, etc. are also under the control of medulla oblongata.
3. Medulla oblongata is essential for all the vital functions of the body.

Question 4.
Spinal cord.
Answer:
Functions of spinal cord:

1. Spinal cord is the main pathway for conduction of sensory and motor nerve impulses.
2. The sensory impulses travel from the body
   to the brain and the motor impulses travel from the brain to the body.
3. Spinal reflexes are controlled by spinal cord.
4. The spinal cord reduces the load on the brain by taking appropriate actions in a reflex way.

Question 5.
Pituitary gland.
Answer:
Functions of pituitary:

1. Pituitary secretes seven main hormones viz. ACTH, TSH. GH or STH, LTH or Prolactin, MSH and gonadotropins such as FSH, LH or ICSH.
2. These hormones are secreted upon receiving proper releasing factor from hypothalamus.
3. These hormones bring about many coordinating functions in the body. Almost all endocrine glands are under the control of these hormones.
4. The neurohypophysis part stores two hormones, viz. vasopressin and oxytocin which are secreted by hypothalamus.
5. Important functions such as growth and reproductive processes, pregnancy, childbirth, lactation, etc. are under the control of pituitary.
6. Neurohypophysis acts as a neurohaemal organ and stores the hormones for some time.

Question 6.
Functions of hormones secreted by the thyroid gland.
Answer:

1. Thyroxine is the main metabolic hormone in the body.
2. Thyroxine maintains basal metabolic rate (BMR) by increasing glucose oxidation. It brings about calorigenic effect by energy production.
3. It also controls normal protein synthesis.
4. The physical growth, development of gonads and development of mental faculties is under the control of thyroxine.
5. It controls tissue differentiation during metamorphosis particularly in amphibia.
6. Body weight, respiration rate, heart rate, blood pressure, temperature, digestion, etc. is regulated by thyroxine.
7. Another hormone of thyroid, i.e. calcitonin regulates calcium metabolism of the body.

Question 7.
Give significance of relaxin and inhibin.
Answer:
1. Relaxin : Relaxin relaxes the cervix of the pregnant female and ligaments of pelvic girdle during parturition.
2. Inhibin : Inhibin inhibits the FSH and GnRH production.

Question 8.
Enlist hormones secreted by GI tract and state their role.
Answer:
Gastrointestinal tract:
In the gastrointestinal mucosa, certain ells are endocrine in function. These cells produce hormones which play vital role in digestive processes and flow of digestive juices.

1. Gastrin : This hormone stimulates gastric glands to produce gastric juice.
2. Secretin : This hormone is responsible for secretion of pancreatic juice and bile from pancreas and liver.
3. Cholecystokinin CCK/Pancreozymin PZ : This hormone stimulates gall bladder to release bile and stimulates the pancreas to release its enzymes.
4. Entero-gastrone/Gastric inhibitory peptide (GIP) : It slows gastric contractions and inhibits the secretion of gastric juice.

Distinguish between the following

Question 1.
Electrical and chemical synapses:
Answer:

Question 2.
Sympathetic and parasympathetic nervous system.
Answer:

Question 3.
Unconditional reflexes and Conditional reflexes
Answer:

Question 4.
Epithalamus and hypothalamus.
Answer:

Question 5.
Dura mater and pia mater.
Answer:

Question 6.
Cerebrum and cerebellum
Answer:

Question 7.
Cranial nerves and Spinal nerves
Answer:

Question 8.
Extero and entero receptors.
Answer:

Question 9.
Adenohypophysis and neurohypophysis.
Answer:

Question 10.
FSH and LH
Answer:

Question 11.
Glucocorticoids and mineralcorticoids
Answer:

Give scientific reasons

Question 1.
Number of gyri is related to the degree of intelligence.
Answer:

1. Gyri are the ridges in the folds present on the cerebral cortex.
2. The number of folds increase the surface area of the cerebral cortex.
3. Cerebral cortex has sensory and motor areas such as Wernicke’s area, Broca’s area, etc. If the surface area is greater, the neurons in these areas are also more in number.
4. Greater the number of neurons greater is the intelligence.
5. The number of gyri therefore is said to be related to the degree of intelligence.

Question 2.
A drunken person cannot maintain balance of the body.
Answer:

1. Cerebellum is the primary centre for controlling equilibrium and balance of the body.
2. Alcohol has an adverse effect on the neurons of cerebellum.
3. Consciousness of brain is also controlled by cerebellum.
4. When a person is drunk, the alcohol in his or her blood affects the activities of cerebellum and hence the person cannot maintain the balance of the body.

Question 3.
We are able to understand the smell of the first showers of rain or the sudden changes in the climate.
Answer:

1. We are able to understand any smell because of our olfactory mucosa and olfactory lobes of the brain.
2. Volatile substances are received by the olfacto-receptors in the nose.
3. Nerve impulse generated are carried by olfactory nerve and transmitted to brain where the impulse is interpreted.
4. The characteristic earthy smell is due to a compound ‘geosmin’.
5. Geosmin is produced by some species of Streptomyces [ gram positive soil bacterium],
6. Similarly, sudden change in the climate is easily noticed in the form of temperature change in the surrounding.
7. This change is detected by caloreceptors of the skin. From these receptors the signal is transmitted to CNS where the change is perceived.

Question 4.
We are able to hear the chirping of the birds and recognize the sound of the bird.
Answer:

1. The phonoreceptors of the body receive the sound waves and transfer the nerve impulses to the auditory areas of the brain.
2. The interpretation, of the sound is a combined effort of sensory and association areas [auditory areas] of temporal lobes of the brain.
3. This is how we are able to hear the chirping of the birds and recognize the sound of the bird.

Question 5.
We can see and enjoy the beautiful colours of the nature after the sunrise.
Answer:

1. The light receptor are present in the retina of eyes.
2. These are photosensitive rod and cone cells. Cone cells are sensitive to bright light-and colours.
3. On receiving the light rays, these cells convert them into nerve impulses.
4. The cones are of three types, which contain their own characteristic photo-pigments that respond to red, green and blue lights.
5. Various combinations of these cones and their photo pigments produce sensation of different colours.
6. These impulses are carried to the visual cortex of the occipital lobe where the image is interpreted.
7. In this manner, we can see and enjoy the beautiful colours of the nature after the sunrise.