CBSE Class 12 Biology Strategies for Enhancement in Food Production Assignment Set 02

Question: …… is the agricultural practice of feeding, breeding and raising livestock. Choose the most appropriate word to fill
in the blank.
a) Animal husbandry
b) Cattle improvement
c) Both (a) and (b)
d) Cattle farming

Answer: a

Question: The process of fusion of protoplast of somatic cells obtained from different varieties or species of plant on a suitable
nutrient medium in vitro to develop a somatic hybrid is called
a) somatic hybridisation
b) cross hybridisation
c) intravarietal hybridisation
d) interspecific hybridisation

Answer: a

Question: Crustacean fishery is connected with exploitation of
a) oysters and crabs
b) mussels and squids
c) shell and cuttle fish
d) crabs and prawn

Answer: d

Question: Himgiri developed by hybridisation and selection for disease resistance against rust pathogens is a variety of
a) chilli
b) maize
c) sugarcane
d) wheat

Answer: d

Question: Choose the correct option.
a) More than 70% of the world livestock population is in India and China
b) The contribution of India and china to the world farm produce is about 25%
c) Important livestock of India are cattle and buffaloes
d) All of the above

Answer: d

Question: What measures should be taken for cattles, to realise the yield potential?
a) They have to be housed well
b) Feeding should be in scientific manner
c) Hygienic milking, storage and transport of milk
d) All of the above

Answer: d

Question: Which of the following is an aim of animal breeding?
a) Increasing the yield of animals
b) Improving the desirable qualities of the produce
c) Producing better looking animals
d) Both (a) and (b)

Answer: d

Question: The term ‘inbreeding’ refers to
a) mating of more closely related individuals within the same breed for 4-6 generations
b) mating of unrelated animals of the same breed
c) mating of animals within the same breed, but having no common ancestors up to 4-6 generations
d) superior males of one breed are mated with superior females of another breed

Answer: a

Question: A superior female, in the case of cattle is the …A… that produces more milk per lactation. On the other hand, a superior male is the …B…, which gives rise to …C… as compared to those of other males. Here, A to C refers to
a) A–cow, B–bull, C–superior progeny
b) A–buffalo, B–bull, C–inferior progeny
c) A–cow, B–bull, C–inferior progeny
d) A–cow, B–bull, C–normal progeny

Answer: a

Question: Suggest a way to overcome inbreeding depression.
a) Selected animals should be mated with related superior animals of different breed
b) Selected animals should be mated with unrelated superior animals of same breed
c) Selected animals should be mated with related superior animals of same breed
d) Selected animals should be mated with unrelated superior animals of different breed

Answer: b

Question: The practices concerned with the improvement in animal husbandry include
a) management of farm and farm animals
b) management of animals and plants at a same place
c) genetic engineering
d) None of the above

Answer: a

Question: When breeding is between the unrelated animals, including individuals of the same breed but having no common ancestors for 4-6 generations or between different breeds or different species, is called
a) outbreeding
b) inbreeding
c) controlled breeding
d) hybridisation

Answer: a

Question: During MOET at which of the following stages, embryo is transferred to surrogate mothers
a) Unfertilised ovules
b) 2-celled stage
c) Fertilised egg
d) 8-32 celled stage

Answer: d

Question: The technique of regeneration of whole plant from any part of a plant by allowing it to grow on a suitable culture under aseptic sterile conditions in vitro is called
a) tissue culture
b) plant culture
c) micropropagation
d) somatic hybridisation

Answer: a

Question: In which of the following techniques high milk giving breeds of females and high quality meat giving bulls have been bred successfully to increase herd size short time?
a) MOET
b) Artificial insemination
c) Interspecific hybridisation
d) Induced mutation

Answer: a

Question: Controlled breeding experiments are carried out using
a) interspecific hybridisation
b) artificial insemination
c) outcrossing
d) intraspecific hybridisation

Answer: b

Question: Which of the following given point is important for successful bee-keeping?
a) Knowledge of the nature and habits of bees
b) Selection of suitable location for keeping the beehives
c) Catching and hiving of swarms (group of bees) and their management during different seasons
d) All of the above

Answer: d

Question: Green revolution in India was possible due to
a) exploitation of high yielding varieties
b) intensive cultivation
c) better irrigation, fertilisers and pesticide facilities
d) All of the above

Answer: d

Question: In case of plant breeding, cross hybridisation is a time consuming and tedious process because
a) pre-existing genetic variability is collected from wild varieties, species and relatives of the cultivated crop species
b) it involves the selection of plants among the progeny of the hybrids with desired combination of characters
c) it involves emasculation and bagging techniques to transfer desired pollen grains to the stigma of desired plant
d) None of the above

Answer: c

Question: Which of the following is not a freshwater fishes?
a) catla
b) rohu
c) common carp
d) mackerel

Answer: d

Question: During selection and testing of superior recombinants, selected superior plants are self-pollinated for several generation. Why?
a) So that they reach a state of uniformity (homozygosity)
b) So that the characters will not segregate in the progeny
c) Both (a) and (b)
d) Selected superior plants are not self-pollinated but cross-pollinated

Answer: c

Question: Where Taichung Native-1 was developed?
a) Taraiva
b) Tokyo
c) Tallinn
d) Taiwan

Answer: d

Question: Which of the following points should be kept into consideration for management of poultry farm?
A. Selection of disease free and suitable breeds
B. Proper and safe farm conditions
C. Proper feed and water
D. Hygiene and healthcare
a) A,B,C
b) A,C,D
c) A,B,C,D
d) None of these

Answer: c

Question: Saccharum barberi and Saccharum officinarum are varieties of
a) sugarcane
b) maize
c) wheat
d) rice

Answer: a

Question: Method(s) of breeding plants for acquiring disease resistance is/are
a) conventional breeding techniques
b) mutation breeding
c) tissue culture
d) Both (a) and (b)

Answer: d

Question: The process by which genetic variations are created through changes in the base sequences within genes is
a) plant breeding
b) interspecific hybridisation
c) outcrossing
d) mutation

Answer: d

Question: To meet the demands of the society, in vitro production of a large number of plantlets in a short duration is practiced in floriculture and horticulture industry today. It is called
a) somatic hybridisation
b) micropropagation
c) hybridoma technology
d) somaclonal variation

Answer: b

27. Some released crop varieties bred by hybridisation and selection, for insect pest resistance are given in the table.
Fill up the blanks.

a) A–Pusa Karan, B–Flat bean, C–Bhindi
b) A–Pusa Gaurav, B–Flat bean, C–Okra
c) A–Pusa Shubhra, B–Wrinkled bean, C–Pea
d) A–Pusa Komal, B–Smooth bean, C–Bhindi

Answer: b

Question: Hidden hunger is best indicated as
a) inability of majority of people to buy enough fruits, vegetables, legumes, fish and meat and thus suffer from deficiency of vitamin, protein, etc.
b) people are unable to buy healthy drink item and thus suffer from deficiency
c) people are unable to buy junk food thus suffer from deficiency
d) All of the above

Answer: a

Question: Semidwarf variety of wheat was developed at
a) International Centre for Wheat and Maize Improvement Brazil
b) International Centre for Wheat and Maize Improvement Mexico
c) International Centre for Wheat and Rice Improvement Japan
d) International Centre for Wheat and Gram Improvement Mexico

Answer: b

Question: Single cell protein is an alternative protein source for animal and human nutrition formed from certain beneficial microorganisms like
a) Spirulina
b) Methylophilus methylotrophus
c) Both (a) and (b)
d) None of the above

Answer: c

Question: Somatic hybrids are produced by the fusion of …… .
a) protoplasts of two cells
b) cytoplasm of two cells
c) nucleus of two cells
d) DNA of two cells

Answer: a

Question: Pomato is a somatic hybrid of
a) potato and onion
b) potato and tomato
c) potato and brinjal
d) brinjal and tomato

Answer: b

Point to Remwmber

Apiculture : Rearing of honeybees for the production of honey, beewax, royal jelly and bee Venom.

Artificial insemination : Introduction of semen of good quality of male into the vagina of female.

Explant : A part of plant excised from its original location and used for tissue culture.

Germplasm Collection : The entire collection having all the diverse alleles for all the genes in the given organism.

Inbreeding depression : Continued close inbreeding decreases the fertility and productivity.

Inbreeding : Inbreeding refers to the mating of more closely related individuals within the same breed for 4-6 generations.

Out-breeding : Out-breeding is the breeding of the unrelated animals, which may be between individuals of the same breed (but having no common
ancestors), or between different breeds (cross breeding or different species (interspecific hybridisation).

Super Ovulation : Stimulation of good female animal by administering hormones to produce more eggs.

Mutation breeding : Mutation in plants in induced artificially through use of mutagens to obtain desirable characters. These plants (as a source) are used
in breeding.

Totipotency : The ability to generate a whole plant from any cell/explant.

Important Questions for NCERT Class 12 Biology Strategies for Enhancement in Food Production

I. ANIMAL HUSBANDARY

VSA (1 MARK)

Question 1. Why is inbreeding necessary in animal husbandry?
Answer: Inbreeding increases homozygosity and helps in evolving a pureline in any animal. It also helps in accumulation of superior genes and elimination of less desirable genes.
In simple words: Inbreeding makes animals genetically pure and helps develop superior breeds by grouping good genes together.

Exam Tip: Mention the keyword homozygosity to secure full marks.

Question 2. Name two fungal diseases of crop plants.
Answer: Two fungal diseases of crop plants are:
1. Brown rust of wheat
2. Late blight of potato
In simple words: Fungi cause diseases in crops, such as rust in wheat and blight in potatoes.

Exam Tip: Always specify the crop name along with the disease for clarity.

Question 3. Which product of apiculture is used in cosmetics and polishes?
Answer: Beeswax, a product obtained from apiculture (bee-keeping), is widely used in the preparation of cosmetics and polishes.
In simple words: Beeswax is used to make products like creams, lipsticks, and polishes.

Exam Tip: Remember that beeswax is secreted by the wax glands of worker bees.

Question 4. Semi-dwarf varieties of a crop plant were derived from IR-8. Name that crop.
Answer: Paddy (Rice)
In simple words: The IR-8 rice variety was used to develop semi-dwarf rice varieties.

Exam Tip: Mention both Paddy and Rice to be completely accurate.

Question 5. Write two qualities of Saccharum officinarum (Sugarcane) grown in South India.
Answer: The two qualities of Saccharum officinarum grown in South India are:
1. Thicker stems
2. Higher sugar content
In simple words: South Indian sugarcane has thicker stems and more sugar compared to North Indian varieties.

Exam Tip: Contrast this briefly with North Indian sugarcane (Saccharum barberi) which had poor sugar content and thinner stems for better conceptual understanding.

SA-II (2 MARKS)

Question 6. A new breed of sheep was developed in Punjab by crossing two different breeds of Sheep. Name the two breeds which were crossed and the new breed developed.
Answer: The new breed of sheep developed in Punjab is called Hisardale. It was produced by cross-breeding Bikaneri ewes and Marino rams.
In simple words: Hisardale sheep was created in Punjab by crossing Bikaneri ewes with Marino rams.

Question 7. Study the table given below and fill in the blanks marked A, B, C and D
 

Answer:
A = Leaf and stripe rust, hill bunt
B = Pusa swarnim (Karan rai)
C = Cowpea
D = Pusa Sadabahar
In simple words: The table lists disease-resistant crop varieties developed through breeding.

Exam Tip: Learn standard crop varieties and their specific disease resistance profiles given in NCERT table 9.1.

Question 8. Why are proteins synthesized from Spirulina called Single celled Proteins? What is the significance of such a protein?
Answer: Proteins synthesized from microorganisms like Spirulina are called Single Cell Protein (SCP) because they are obtained from unicellular microbes that serve as a source of mixed protein rich in essential amino acids.
Significance:
1. It provides a protein-rich diet for human consumption to help tackle malnutrition.
2. It is an alternative protein source for animal feed.
3. Microbes have an enormous growth rate, enabling rapid mass production of food.
In simple words: Spirulina protein is called Single Cell Protein because it comes from single-celled organisms, providing a fast and abundant source of nutrition.

Exam Tip: Highlight that SCP helps reduce environmental pollution while producing high-protein food using waste materials.

Question 9. Differentiate between inbreeding and outbreeding in animals.
Answer:
 

In simple words: Inbreeding is mating within close relatives of the same breed, whereas outbreeding is mating between unrelated animals.

Exam Tip: Use a tabular format for differentiation questions to score maximum marks.

Question 10. Observe the process of Somatic hybridisation given below and fill in the blanks. (i), (ii), (iii) and (iv)
Tomato Cell + Potato Cell → Cell wall digesting enzyme → (i) → Fusion → (ii) → Name of the process → (iii) → Name of the plants → (iv) → Term used to denote such plants.
Answer:
(i) Isolation of protoplasts of tomato cell and potato cell
(ii) Somatic hybridisation
(iii) Pomato
(iv) Somatic hybrid
In simple words: Protoplasts of tomato and potato are fused to form a somatic hybrid called pomato.

Exam Tip: Clearly mention the sequence from isolated protoplast to somatic hybrid generation.

SA I (3 MARKS)

Question 11. What is micropropagation? Why are plants produced by this technique called somaclones? Name any two food plants which are produced on commercial scale using this method.
Answer: The method of producing thousands of plants through tissue culture is called micropropagation.
Plants produced through micropropagation are genetically identical to the original plant from which they were grown because they are derived from somatic cells without meiosis or gametic fusion; hence, they are called somaclones.
Commercial food plants produced using this method: Tomato, banana, and apple.
In simple words: Micropropagation is rapid plant multiplication via tissue culture, and the resulting clones are genetically exact copies of the parent plant.

Question 12. What is mutation? Explain the significance of mutation in plant breeding. Give an example of a disease resistant variety of cultivated plant induced by mutation.
Answer: Mutation is a sudden inheritable change in the characters of an organism due to an alteration in the sequence of bases in its DNA/genes.
Significance in plant breeding:
1. It introduces new traits and variations not found in the parental type.
2. Mutagens like gamma radiations can be artificially applied to induce desirable characters.
3. Mutated plants can be directly used or crossed with other varieties to breed improved cultivars.
Example: Mung bean variety resistant to yellow mosaic virus and powdery mildew was developed through mutation breeding.
In simple words: Mutation creates new genetic traits that help breeders develop disease-resistant crop varieties.

Exam Tip: Quote the specific mung bean example for virus and mildew resistance.

Question 13. How can we improve the success rate of fertilisation during artificial insemination in animal husbandry programmes?
Answer: The success rate of fertilization during artificial insemination can be significantly improved by using Multiple Ovulation Embryo Transfer (MOET) technology.
Procedure:
1. A cow is administered hormones with FSH-like activity to induce follicular maturation and superovulation.
2. Instead of one egg, 6 to 8 eggs are produced per cycle.
3. The cow is either mated with an elite bull or artificially inseminated.
4. Fertilized eggs at the 8-32 celled stages are recovered non-surgically and transferred to surrogate mothers.
In simple words: MOET uses hormone treatment to make a cow produce multiple eggs at once, increasing the chances of successful breeding.

Exam Tip: Mention the hormone (FSH) and the embryonic stage (8-32 cells) for complete accuracy.

Question 14. Biofortification is the most practical means to improve public health. Justify the statement with examples.
Answer: Biofortification is the breeding of crops with higher levels of vitamins, minerals, higher protein, and healthier fat content. It directly targets improving public health and preventing hidden hunger.
Examples:
1. Maize hybrids developed with twice the amount of amino acids lysine and tryptophan.
2. Wheat variety Atlas 66, having a high protein content.
3. Rice variety having 5 times iron compared to normal amounts.
In simple words: Biofortification adds essential nutrients directly into staple crops to fight malnutrition and improve community health.

Exam Tip: List at least two specific crop examples with their nutrient enhancements (e.g., Atlas 66 wheat for protein).

Question 15. What is meant by germplasm collection? Describe its significance in plant breeding programmes.
Answer: Germplasm collection refers to the entire collection of plants or seeds having all the diverse alleles for all genes in a given crop and its related species.
Significance in plant breeding:
1. It serves as the reservoir of all genetic variability and traits available for a crop.
2. Plant breeders evaluate and select desirable alleles from the germplasm to transfer them into elite parents to create improved varieties.
In simple words: Germplasm collection is a stockroom of diverse plant genes used by breeders to select desirable characters for new crops.

Exam Tip: Use the term allele and genetic variability to score full marks.

Question 16. To which product do the following products relate: (a) Blue revolution (b) White revolution (c) Green revolution?
Answer:
(a) Blue revolution is related to Fish production (Aquaculture/Pisciculture).
(b) White revolution is related to Milk production.
(c) Green revolution is related to Crop production (food grain production).
In simple words: Blue is for fish, white is for milk, and green is for crops.

Exam Tip: Keep the answers precise and direct for matching questions.

LA-I (5 MARKS)

Question 17. Does apiculture offer multiple advantages to farmers? List its advantages, if it is located near a place of commercial flower cultivation. Name the most common species of bee which is reared in India.
Answer: Yes, apiculture offers multiple benefits to farmers. In addition to honey production, bees yield beeswax, which is widely used in industries for cosmetics and polishes.
Advantages when located near commercial flower cultivation:
1. Pollination: Bees act as efficient pollinators for many crop species, including commercial and flowering crops like sunflower, which significantly improves crop yield.
2. Increased Honey Yield: Access to abundant floral nectar enhances the quantity and quality of honey produced.
Most common species of bee reared in India: Apis indica.
In simple words: Beekeeping near flower farms boosts honey production and helps pollinate crops to increase food yields.

Exam Tip: Mention both economic products (honey, beeswax) and ecological benefits (pollination) to secure full credit.

Question 18. What is somatic hybridisation? Describe the various steps in producing somatic hybrids from protoplasts. Mention any two uses of somatic hybridisation.
Answer: Somatic hybridisation is the process of isolating protoplasts from somatic cells of two different varieties or species of plants and fusing them to obtain a hybrid protoplast, which can be grown to form a somatic hybrid.
Steps in producing somatic hybrids:
1. Isolation of cells and digestion of their cell walls using wall-digesting enzymes (pectinase and cellulase) to obtain naked protoplasts.
2. Fusion of protoplasts from selected parents is induced using agents such as polyethylene glycol (PEG) or electrical stimulation.
3. Culturing the resulting hybrid protoplast on a suitable nutrient medium to regenerate its cell wall.
4. The resulting cells undergo division to form plantlets (somatic hybrids).
Uses/Applications:
1. Creation of novel interspecific hybrids (somaclonal variations) that cannot be produced by normal sexual crossing (e.g., Pomato).
2. Raising allopolyploids and disease-resistant plant lines.
In simple words: Somatic hybridisation fuses plant cells without sexual reproduction to create unique hybrid plants with useful traits.

Exam Tip: List the specific enzymes (pectinase and cellulase) and fusion agent (PEG) as they are mandatory keywords for evaluation.