Maharashtra Board Class 12 Biology Important Questions Chapter 12 Biotechnology

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.

Column A	Column B
(1) Sir Edward Sharpey Schafer	(a) Chemically synthesized DNA sequence of insulin
(2) Hakura	(b) Discovery of insulin
(3) Gilbert and Villokomaroff	(c) PCR
(4) K. Mullis	(d) Insulin production using r-DNA technology

Answer:

Column A	Column B
(1) Sir Edward Sharpey Schafer	(b) Discovery of insulin
(2) Hakura	(a) Chemically synthesized DNA sequence of insulin
(3) Gilbert and Villokomaroff	(d) Insulin production using r-DNA technology
(4) K. Mullis	(c) PCR

Question 2.

Restriction enzyme	Recognition sequence
(1) Alu I	(a) 5′ G-A-A-T-T-C 3′ 3′ C-T-T-A-A-G 5’
(2) Bam HI	(b) 5′ G-T-C-G-A-C3′ 3′ C-A-G-C-T-G 5′
(3) Eco RI	(c) 5′ A-G-C-T 3′ 3′ T-C-G-A5′
(4) Hind II	(d) 5′ G-G-A-T-T-C 3′ 3′ C-C-T-A-A-G 5′

Answer:

Restriction enzyme	Recognition sequence
(1) Alu I	(c) 5′ A-G-C-T 3′ 3′ T-C-G-A5′
(2) Bam HI	(d) 5′ G-G-A-T-T-C 3′ 3′ C-C-T-A-A-G 5′
(3) Eco RI	(a) 5′ G-A-A-T-T-C 3′ 3′ C-T-T-A-A-G 5’
(4) Hind II	(b) 5′ G-T-C-G-A-C3′ 3′ C-A-G-C-T-G 5′

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.

Column A: (Transgenic animal)	Column B : (Application)
(a) Transgenic mice	——————
(b) Transgenic cattle	——————
(c) Pig clones	——————
(d) Transgenic fish	——————

Answer:

Column A: (Transgenic animal)	Column B : (Application)
(a) Transgenic mice	(ii) Cancer research
(b) Transgenic cattle	(iv) Supply of factor IX
(c) Pig clones	(i) Provide tissues for human transplants
(d) Transgenic fish	(iii) E. coli hygromycin resistant gene

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:

Old or classical biotechnology	Modem biotechnology
1. It is mainly based on fermentation technology.	1. It is based on genetic engineering and chemical engineering.
2. It does not involve alteration or modification of genetic material of organisms to develop specific Product.	2. It involves the alteration or modification of genetic material of organisms to develop specific product.
3. It does not involve the use of r-DNA technology, polymerase chain reaction (PCR), microarrays, cell culture and fusion, and bioprocessing to develop products.	3. It involves the use of r-DNA technology, polymerase chain reaction (PCR), microarrays, cell culture and fusion, and bioprocessing to develop specific products.
4. There is no ownership of old biotechnology.	4. It involves ownership of technology.
5. Examples : Preparation of curd, ghee, soma, vinegar, yogurt, cheese making, wine making, etc.	5. Examples : Transgenic organisms.

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

Genomic library	c-DNA library
1. It is a collection of clones that represent the complete genome of an organism.	1. It is a collection of clones containing c-DNAs inserted into suitable vectors like phages or plasmids.
2. DNA fragments to be cloned are obtained by cutting genomic DNA by restriction enzymes.	2. c-DNAs are produced by the process of reverse transcription, using complete m-RNA complement obtained from a tissue or an organism.

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

Germ line gene therapy	Somatic cell gene therapy
1. Germ line gene therapy involves modification of genome of germ cells like sperms, eggs, early embryos.	1. Somatic cell gene therapy involves modification of genome of somatic cells like bone marrow cells, hepatic cells, fibroblasts, endothelium, pulmonary epithelial cells, central nervous system and smooth muscle cells of wall of blood vessels.
2. It allows transmission of the modified genetic information to the next generation.	2. It does not allow transmission of the modified genetic information to the next generation.
3. Its application in human beings is not encouraged because of technical and ethical reasons.	3. It is a feasible option and clinical trials are carried out for treatment of various diseases.

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.

RE	Source	End products
Alu I	————-	Blunt ends
————	Bacillus amyloliquefaciens H	Sticky ends
Eco R I	————–	Sticky ends
Hind II	H. influenza Rd	————–

Answer:

RE	Source	End products
Alu I	Arthobacter luteus	Blunt ends
Bam H I	Bacillus amyloliquefaciens H	Sticky ends
Eco R I	E. coli Ry 13	Sticky ends
Hind II	H. influenza Rd	Blunt ends

Question 2.

Substance	Potential benefit	Crop	Transgene
Provitamin A	Anti-oxidant	————–	Phytoene synthase, Lycopene cyclase
Fructans	————–	Sugarbeet	—————-
Vitamin E	—————-	Canola	γ -tocopherol methyl transferase
Flavonoids	Anti-oxident	Tomato	————–
————–	Iron fortification	Rice	Ferritin, metallothioein, phytase

Answer:

Substance	Potential benefit	Crop	Transgene
Provitamin A	Anti-oxidant	Rice	Phytoene synthase, Lycopene cyclase
Fructans	Low calories	Sugarbeet	I – sucrose : sucrose fructosyl transferase
Vitamin E	Anti-oxidant	Canola	γ -tocopherol methyl transferase
Flavonoids	Anti-oxident	Tomato	Chalone isomerase
Iron	Iron fortification	Rice	Ferritin, metallothioein, phytase

Question 3.

Organization	Expand
OECD	——————
GEAC	——————
USDA	——————
USPTO	——————
CSIR	—————–

Answer:

Organization	Expand
OECD	Organization for Economic Cooperation and Development
GEAC	Genetic Engineering Approval Committee
USDA	US Department of Agriculture
USPTO	US Patent and Trademark Office
CSIR	Council of Scientific and Industrial Research

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.