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

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.

Column I (Biofortified crop)	Column II (Nutrient Enrichment)
(1) Maize	(a) Five times more iron
(2) Rice	(b) Twice the amount of lysine and tryptophan
(3) Wheat Atlas-66	(c) Enriched in vitamin A and minerals
(4) Carrots, spinach	(d) High protein content

Answer:

Column I (Biofortified crop)	Column II (Nutrient Enrichment)
(1) Maize	(b) Twice the amount of lysine and tryptophan
(2) Rice	(a) Five times more iron
(3) Wheat Atlas-66	(d) High protein content
(4) Carrots, spinach	(c) Enriched in vitamin A and minerals

Question 2.

Column I (Organic Acids]	Column II (Microbial source)
(1) Citric acid	(a) Rhizopus arrhizus
(2) Fumaric acid	(b) Acetobacter aceti
(3) Gluconic acid	(c) Aspergillus niger
(4) Acetic acid	(d) Aspergillus niger

Answer:

Column I (Organic Acids]	Column II (Microbial source)
(1) Citric acid	(c) Aspergillus niger
(2) Fumaric acid	(a) Rhizopus arrhizus
(3) Gluconic acid	(d) Aspergillus niger
(4) Acetic acid	(b) Acetobacter aceti

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

Column A (Biocontrol agents)	Column B (Host)
Microbial pesticide	————
Mycoherbicide	————
Insect as herbicide	————–
Bacterial herbicide	—————

Answer:

Column A (Biocontrol agents)	Column B (Host)
Microbial pesticide	Beavueria bassiana
Mycoherbicide	Alternaria crassa
Insect as herbicide	Cactoblastis cactorum
Bacterial herbicide	Agrobacterium spp.

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

Resistance to insects	Morphological characters
Jassids	————
Cereal leaf beetle	————
Stem borers	————–
Bollworms	—————

Answer:

Resistance to insects	Morphological characters
Jassids	Hairy leaves in cotton
Cereal leaf beetle	Hairy leaves in wheat
Stem borers	Solid stem in wheat
Bollworms	Nectar-less cotton having smooth leaves

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:

Callus Culture	Suspension culture
1. Solid nutrient medium is used in callus culture.	1. Liquid nutrient medium is used in suspension culture.
2. No shaker or agitator is needed.	2. Shaker or agitator is needed.
3. Cells of explants divide and redivide to form callus.	3. Callus is not formed.
4. Callus a mass of undifferentiated cells.	4. Suspension culture consists of single isolated cells or small groups of cells.
5. It shows slow growth.	5. It shows faster growth.

Question 2.
Outcrossing and Crossbreeding.
Answer:

Outcrossing	Crossbreeding
1. Breeding of animals of the same breed but having no common ancestors for 4 to 6 generations is known as outcrossing.	1. Breeding of superior male of one breed with superior female of another breed is known as crossbreeding.
2. Progeny is known as outeross.	2. Progeny is known as hybrid.
3. New breeds are not developed by outcrossing.	3. New breeds or hybrids are formed by crossbreeding.
4. An outcross helps to overcome inbreeding depression.	4. Hybrids are subjected to inbreeding and new stable breeds are developed by crossbreeding.

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

Inorganic fertilizers	Organic fertilizers / biofertilizers
1. They are non-renewable nutritional resources.	1. They are renewable nutritional resources.
2. Inorganic fertilizers are synthetic and are in the form of chemicals.	2. They are biological in origin.
3. They are mixtures of mineral salts of NPK in definite proportions.	3. Organic fertilizers are farmyard manure, green manure and compost. Whereas, bio fertilizers are live bacterial, cyanobacterial (mostly N<sub>2</sub> fixing) or fungal formulations which enhance the nutrient quality of soil.
4. Excessive use of inorganic fertilizers results in pollution of soil, groundwater and air.	4. They do not cause pollution.
5. They are not part of sustainable agriculture.	5. They are part of organic farming and sustainable agriculture.

Question 4.
Ectomycorrhizae and Endomycorrhizae.
Answer:

Ectomycorrhizae	Endomycorrhizae
1. Mycelium of ectomycorrhizal fungi form a sheath called mantle on the surface of roots.	1. Most of the endomycorrhizal hyphae penetrate in the root cortex.
2. Few hyphae form hartig-net in the intercellular spaces of root cortex.	2. Fungal hyphae do not produce hartig-net.
3. Arbuscles and vesicles are not formed.	3. Arbuscles and vesicles are formed.

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.

Crop	Variety	Resistant to disease
Wheat	————–	Leaf and stripe rust, Hill bunt
————-	Pusa swarnim	White rust
Cauliflower	————–	Black rot and Curl blight black rot
Chilli	Pusa sadabahar	—————

Answer:

Crop	Variety	Resistant to disease
Wheat	Himgiri	Leaf and stripe rust, Hill bunt
Brassica	Pusa swarnim	White rust
Cauliflower	Pusashubhra	Black rot and Curl blight black rot
Chilli	Pusa sadabahar	Chilli mosaic virus, Tobacco mosaic virus, leaf curl

Question 2.
Complete the table given below.

Crop	Variety	Insect pest
Brassica	Pusa Gaurav	————-
————-	Pusa sem 2 m Pusa sem 3	Jassids, aphids, fruit borer
Okra	————–	Shoot and fruit borer

Answer:

Crop	Variety	Insect pest
Brassica	Pusa Gaurav	Aphids
Flat bean	Pusa sem 2 m Pusa sem 3	Jassids, aphids, fruit borer
Okra	Pusa Sawani, Pusa A-4	Shoot and fruit borer

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.