2nd PUC Biology Question Bank Chapter 9 Strategies For Enhancement in Food Production

Students can Download 2nd PUC Biology Chapter 9 Strategies For Enhancement in Food Production Questions and Answers, Notes Pdf, 2nd PUC Biology Question Bank with Answers helps you to revise the complete Karnataka State Board Syllabus and to clear all their doubts, score well in final exams.

Karnataka 2nd PUC Biology Question Bank Chapter 9 Strategies For Enhancement in Food Production

2nd PUC Biology Strategies For Enhancement in Food Production One Mark Questions and Answers

Question 1.
Define animal husbandry.
Answer:
It is the science of systematic breeding and raising of domesticated animals as per human requirement.

Question 2.
Define micro-propagation.
Ans.
The method of producing very large number of plants through tissue culture is known as micro-propagation.

Question 3.
What is SCP?
Answer:
Single Cell protein.

2nd PUC Biology Question Bank Chapter 9 Strategies For Enhancement in Food Production

Question 4.
Define apiculture?
Answer:
The maintenance of the hives of honey bees for the production of honey.

Question 5.
What is inbreeding depression?
Answer:
The continuous inbreeding especially close inbreeding may lead to reduced fertility and productivity. This is called inbreeding depression.

Question 6.
What is an explant?
Answer:
A small part or piece of plant is collected from the desired and disease free plant. These plant parts taken for culture are called explant.

Question 7.
What is somatic hybridization?
Answer:
The process of physical fusion of two different protoplasts of somatic cells of plants is called somatic hybridization.

Question 8.
What is callus?
Answer:
The explants in the culture tubes divide and redivide, producing undifferentiated mass of cells called callus.

Question 9.
A protoplast of tomato plant is fused with that of potato to form a new hybrid plant. Name the hybridization technique involved here.
Answer:
Somatic hybridzation.

Question 10.
What is totipotency?
Answer:
The capacity to generate a whole plant from any cell of an explant is called totipotency.

2nd PUC Biology Question Bank Chapter 9 Strategies For Enhancement in Food Production

Question 11.
Define aquaculture.
Answer:
The culturing of aquatic organisms in fresh water, brackish and marine environments is called aquaculture.

Question 12.
Mention any two common fresh water fishes.
Answer:
Catla and Rohu.

2nd PUC Biology Strategies For Enhancement in Food Production Two Marks Questions and Answers

Question 1.
Name two diseases caused by viruses in crop plants.
Answer:
The diseases are: Tobacco mosaic and turnip mosaic.

Question 2.
Find out the various components of the medium used for propagation of an explant in invitro are?
Answer:
The major components of the medium are :

  • H20
  • Agar-Agar
  • Sucrose
  • Inorganic salts
  • Vitamins
  • Amino acids
  • Growth hormones.

Question 3.
Give one example of the disease caused each by fungi, bacteria and viruses in crop plant.
Answer:

  • Fungal disease: Red rot of sugarcane, Brown rust of wheat.
  • Bacterial disease: Citrus canker, Black rot of crucifers.
  • Viral disease: Turnip mosaic, tobacco mosaic.

Question 4.
What is meant by the term ‘breed’? What are the objectives of animal breeding?
Answer:
A group of animals related by ancestry and similar in most characters like general appearance, features, size, etc., is termed as a breed. The main objective of animal breeding includes, increase in the production and improvement in the quality of animal produce (such as milk, egg, meat, wool, honey, wax, etc.)

2nd PUC Biology Question Bank Chapter 9 Strategies For Enhancement in Food Production

Question 5.
Explain what is meant by biofortification.
Answer:
A plant breeding programme that aims at the improved nutritional quality of a crop variety is called biofortification. It is the breeding of crops with higher levels of vitamins and minerals or higher protein and healthier fats. Such a breeding programme is the most practical approach to improve the health of people.

Question 6.
Which part of the plant is best suited for making virus free plants and why?
Answer:
The apical and axillary meristems are the best suited parts of a plant for the production of virus free plants. It is because viruses do not infect apical and axillary meristem due to the absence of reserve food in them.

Question 7.
What is the m&jor advantage of producing plants by micropropagation?
Answer:
Micropropagation enables us to get unlimited number of plants in a limited space and within short time, besides getting pathogen free plants through tissue culture technique.

Question 8.
List the various components of the medium used for propagation of an explant in invitro conditions?
Answer:
Water, inorganic salts, sucrose (as a source of carbon and energy) vitamins, amino acids and growth hormones (like auxins, cytokinins, etc.), It requires a gelling agent like agar-agar added to the liquid medium for its solidification.

Question 9.
What are the advantages of tissue culture?
Answer:
1. Micropropagation: The method of rapid vegetative propagation of desired plants is called micropropagation. Large number of medicinal, ornamental and forest plants can be produced through this technique.

2. Production of virus free plants: Virus free or disease free plants can be produced through meristem culture, as the apical meristems are devoid of virus.

3. Androgenic haploid plants: Haploid plants can be produced through anther or pollen culture. Diploid homozygous plants can be produced from the haploid plants by doubling the chromosome numbers.

4. Induction and selection of mutants: Mutations are induced in the cell cultures and the mutants are then, subjected to herbicides, toxins etc. The mutant cells that show resistance are selected and grown by tissue culture to raise the resistant varieties.

2nd PUC Biology Question Bank Chapter 9 Strategies For Enhancement in Food Production

Question 10.
What is germplasm collection? Mention its importance.
Answer:
The entire collection (of plants/seeds) having all the diverse alleles for all genes in a given 1 crop is called germplasm collection.

Collection and preservation of all the different wild varieties, species and relatives of the cultivated species (followed by their evaluation for their characteristics) is a pre-requisite for effective exploitation of natural genes available in the populations.

Question 11.
What is apiculture? How is it important in our lives?
Answer:
Apiculture is the maintenance of hives of honey bees for the commercial production of honey and wax. Apiculture is a low cost investment and highly profitable industry. It not only provides us honey and wax, but also increases pollination efficiency and improves the yield of the crops.

Question 12.
Discuss the role of fishery in enhancement of food production.
Answer:
Fishery is a kind of industry which is concerned with the catching, processing or selling of fish, shellfish (prawn and molluscs) or other aquatic animals such as crab, lobster, edible oyster, etc. A large section of the Indian population uses fish and many other aquatic animals as food.

These animals serve as a cheap source of animal protein that is easily digestible. Thus, fishery play significant role in enhancement of food production.

Question 13.
What happens if there is a continuous inbreeding? Discuss the strategy to overcome the problem associated with continuous inbreeding.
Answer:

  • The breeding strategy includes the identification of superior males and females of the same breed and mating them in pairs.
  • The progeny of such matings are evaluated and superior males and females are identified for further mating.
  • Inbreeding increases homozygosity and thus inbreeding is necessary for evolving pure line in any animal.
  • Inbreeding exposes the harmful recessive alleles, which become eliminated by selection.
  • Inbreeding also helps in the accumulation of superior genes and elimination of less desirable genes.
  • But, continued inbreeding causes inbreeding depression-that reduces vigour, fertility and even productivity.
  • Under such a situation, the selected animals of the breeding population are mated with unrelated superior animals of the same breed to restore fertility and yield.

2nd PUC Biology Question Bank Chapter 9 Strategies For Enhancement in Food Production

2nd PUC Biology Strategies For Enhancement in Food Production Three Marks Questions and Answers

Question 1.
List three categories of cattle on the basis of their utility. Give one example of each.
Answer:
(a) Milch breeds – Sahiwal
(b) Draught breeds – Hallikar
(c) Dual purpose breeds- Haryana.

Question 2.
Explain in brief the role of animal husbandry in human welfare.
Answer:
Animal husbandry deals with the feeding, breeding and raising of animal livestock for the purpose of obtaining meat and milk. It also includes poultry farming and fisheries. Since a long time, animals have been used by humans for getting products like milk, eggs, meat, wool, silk, honey etc.

We get animal protein from milk, meat and eggs. Fish also constitutes a cheap source of animal protein. Other useful products like wool, honey, wax leather and gelatin etc: are also obtained from animals. Also production of biogas and manure from dung of live stock animals.

Question 3.
Name the methods employed in animal breeding. According to you which of the methods is the best? Why?
Answer:
The methods employed in animal breeding are:

  • inbreeding,
  • out breeding (such as out crossing, cross-breeding and interspecific hybridization) and
  • controlled breeding (such as artificial insemination and multiple ovulation transfer). Controlled breeding is the best method of animal breeding as it ensures good quality progeny. It is also, economic as the semen obtained from a single bull can inseminate many cows housed at far off places.

2nd PUC Biology Question Bank Chapter 9 Strategies For Enhancement in Food Production

Question 4.
Differentiate out-crossing, cross-breeding and interspecific hybridisation.
Answer:
Outcrossing: Outcrossing is the practice of mating of animals of the same breed, but that have no common ancestors on either side of their pedigree upto 4-6 generations.

The offspring of outcrossing, is called an outcross.
A single outcross helps to overcome inbreeding depression.
It is the best breeding method for animals that are below average in productivity and growth rate.

Cross-breeding: It is a method of outbreeding in which superior males of one breed are mated with the superior females of another breed of the same species.
This helps in combining the desirable qualities of the two different breeds into the hybrid progeny.

The hybrid progeny may be directly used for commercial production or they may be subjected to some form of inbreeding and selection, to develop new stable breeds. One example of cross-breeding is Hisardale, a new breed of sheep developed by crossing Bikaneri ewes and Marino rams.

Interspecific hybridisation: It is a method of outbreeding in which male and female animals of two different species are crossed to combine the desirable features of both the parents into one,
e.g. Mule is produced by a cross between a male donkey and a female horse.

Question 5.
Brief note on
1. Inbreeding
2. outbreeding
3. cross breeding.
Answer:
1. Inbreeding:

  • The breeding strategy includes the identification of superior males and females of the same breed and mating them in pairs.
  • The progeny of such matings are evaluated and superior males and females are identified for further mating.
  • Inbreeding increases homozygosity and thus inbreeding is necessary for evolving pure line in any animal.
  • Inbreeding exposes the harmful recessive alleles, which become eliminated by selection.
  • Inbreeding also helps in the accumulation of superior genes and elimination of less desirable genes.
  • But, continued inbreeding causes inbreeding depression-that reduces vigour, fertility and even productivity.
  • Under such a situation, the selected animals of the breeding population are mated with unrelated superior animals of the same breed to restore fertility and yield.

2. outbreeding:

  • Outbreeding refers to the breeding of unrelated animals either of the same breed having no common ancestors for 4-6 generations (out crossing) or of different breeds (cross-breeding) or even different species (interspecific).
  • Outbreeding is of the following types

3. cross breeding:
It is a method of outbreeding in which superior males of one breed are mated with the superior females of another breed of the same species.

This helps in combining the desirable qualities of the two different breeds into the hybrid progeny.

The hybrid progeny may be directly used for commercial production or they may be subjected to some form of inbreeding and selection, to develop new stable breeds. One example of cross-breeding is Hisardale, a new breed of sheep developed by crossing Bikaneri ewes and Marino rams.

2nd PUC Biology Question Bank Chapter 9 Strategies For Enhancement in Food Production

Question 6.
a) What are single cell protein? Mention their significance,
b) Name any two organisms that are used as single cell protein.
Answer:

  • Single cell protein is one of the alternative sources of proteins for nutrition of humans and animals.
  • Microbes are being grown on an industrial scale as source of good protein.
  • Microbes can be grown easily on materials like waste water from potato processing plants (containing starch), straw, molasses, animal manure and even sewage, to produce large quantities and can serve as food, rich in protein, minerals, fats, carbohydrate and vitamins.

Note: It has been calculated that a 250 kg cow produces 200 g of protein per day whereas { 250 g of Methylophilns methylotrophus produces 25 tonnes of protein.

The advantages are that:

  1. SCPs are rich in proteins, minerals, vitamins and carbohydrates and low in fats.
  2. They can be easily grown with cheaper materials like wastewater from potato-processing plants, animal manure, molasses, etc.
  3. The use of waste materials (as culture medium) reduces pollution.
  4. They reduce the pressure on agriculture (for supply of pesticides, fertilizers, etc.) e.g., 250 g of Methylophilus methylotrophus bacterium has been used to produce 25 tonnes of proteins.

Question 7.
Define poultry. Mention the measures to be considered for successful poultry farm management.
Answer:
poultry farm management: Poultry is rearing of domesticated birds (fowl) for meat and eggs.
Poultry typically includes chicken and ducks and sometimes turkey and geese.

The important components of poultry farm management include :

  • Selection of disease-free and suitable breeds.
  • Proper feed and water for the birds.
  • Proper and safe farm conditions.
  • Hygiene and health care of the birds.

2nd PUC Biology Strategies For Enhancement in Food Production Five Marks Questions and Answers

Question 1.
Expand MOET with reference to animal breeding. Describe the process and use of it.
Answer:
Multiple ovulation and embryo transfer.
The steps in the method are as follows :

  • A cow is administered hormones (like FSH) to induce follicular maturation and super ovulation, i.e., production of 6-8 ova in one cycle.
  • The cow is mated with a selected bull or artificially inseminated.
  • The fertilised eggs at 8-32-celled stages are recovered and transferred to surrogate mothers.

This technology has been used for cattle, rabbits, mares, etc.
High milk-yielding breeds of females and high quality meat-yielding bulls have been bred ‘ successfully to increase the herd size within a short time.

2nd PUC Biology Question Bank Chapter 9 Strategies For Enhancement in Food Production

Question 2.
Give a brief account of tissue culture. Also give the advantages of micro propagation.
Answer:
Separation of cells or tissue from plants and growing them on a synthetic nutrient medium under aseptic conditions is called tissue culture.
It involves the following steps:

1. Selection of plant material: The part of the plant used for culture is known as explant. It is isolated from leaves, seeds, roots, buds, nodes etc.

2. Preparation of the culture medium: A suitable culture medium is essential for the growth of explants. A medium is prepared using several macro and micronutrients like sucrose, vitamins, minerals etc. Agar-agar is added as a solidifying agent.

Antibiotics are added to prevent the growth of microbes. Hormones like Auxins and cytokinins are added to promote growth. This medium is sterilised in culture tubes.
There are various nutrient media viz,
(a) M.S. medium
(b) Nitsch’s medium etc

3. Inoculation: It is the process of transfer of explants on to the sterilised culture medium. It is done in a special chamber called Lamina air flow table.

4. Callus formation: It is an undifferentiated mass of cells produced by the explant. It is formed within a short period after inoculation.

5. Organogenesis: It is the process of differentiation of cells in the callus into different ‘ tissues and organs. Root initiation occurs if auxin to cytokinin ratio is high and shoot can be initiated by increasing kinetin to auxin ratio. Embryoids thus obtained are called plantlets.

6. Hardening: Immediate exposure of plantlets obtained from tissue culture to direct sunlight, wind etc may kill them. Therefore they are grown in green houses for a brief period and then gradually transferred to their natural habitats. This is called hardening.

Advantages :
1. Micropropagation: The method of rapid vegetative propagation of desired plants is called micropropagation. Large number of medicinal, ornamental and forest plants can be produced through this technique.

2. Production of virus free plants: Virus free or disease free plants can be produced through meristem culture, as the apical meristems are devoid of viruses.

3. Androgenic haploid plants: Haploid plants can be produced through anther or pollen culture. Diploid homozygous plants can be produced from the haploid plants by doubling the chromosome number.

4. Induction and selection of mutants: Mutations are induced in the cell cultures, and the mutants are then subjected to herbicides, toxins etc. The mutant cells that show resistance are selected and grown by tissue culture to raise the resistant varieties.
2nd PUC Biology Question Bank Chapter 9 Strategies For Enhancement in Food Production 1

2nd PUC Biology Question Bank Chapter 9 Strategies For Enhancement in Food Production

Question 3.
Briefly describe the various steps involved in plant breeding.
Answer:
Plant breeding is the manipulation of plant species in order to create desired plant types that are better suited for cultivation, give better yields and are disease resistant.

1. Collection of variability: Collection and preservation of all the different wild varieties, species and closely related plants of the cultivated species is a pre-requisite for effective exploitation pf natural genes available in the populations. This collection constitutes the germplasm.

2. Evaluation and selection of parents:

  • The germplasm so collected is evaluated to identify plants with desirable characters.
  • The selected plants are multiplied and used in the process of hybridisation.
  • Pure lines are created (by repeated self-pollination) wherever possible and desirable.

3. Cross hybridisation of the selected parents:

  • It involves crossing of two plants which differ in one or more desirable characters to produce a hybrid having the characters of both the parents.
    This is a very time-consuming and tedious process.
  • Also, it is not necessary that the hybrids will combine the desirable characters.

4. Selection and testing of superior recombinants:

  • First the individuals with the desired combination of characters have to be selected from among the progeny of hybrids.
  • Such hybrids are superior to both of the parents (hybrid vigour/heterosis).
  • They are self-pollinated for several generations till they reach a state of homozygosity, so that there will be no segregation of characters in the progeny.

5. Testing, release and commercialisation of new cultivars:
(a) Evaluation:

  • The selected lines are evaluated for their yield and other agronomic traits, disease resistance, etc.
  • Evaluation is done by growing these plants in the research fields and recording their performance under ideal conditions of irrigation, application of fertilisers and other crop management practices.

(b) Testing:

  • The plants selected after evaluation are tested in the farmers’ fields for at least three growing seasons, at several locations in the country, representing different agroclimatic zones, where the crop is normally grown.
  • The material is evaluated in comparison to the best available local cultivar as a reference material.

(c) Release:

  • The material thus selected is certified and released as a variety.

Question 4.
Name any five hybrid varieties of crop plants which have been developed in India.
Answer:
2nd PUC Biology Question Bank Chapter 9 Strategies For Enhancement in Food Production 2

2nd PUC Biology Question Bank Chapter 9 Strategies For Enhancement in Food Production

Question 5.
Define breed. Describe different methods of animal breeding and mention their significance.
Answer:
Animal Breeding:
Animal breeding aims at:
Increasing the quantity of yield and improving the quality of the produce.
Note : Breed : A group of animals related by descent and similar in most characters like general appearence, features, size, configuration etc is known as a breed.
Rearing of breeds on scientific lines is called Breeding.

Breeding is of the following types :
(a) Inbreeding :

  • The breeding strategy includes the identification of superior males and females of the same breed and mating them in pairs.
  • The progeny of such matings are evaluated and superior males and females are identified for further mating.
  • Inbreeding increases homozygosity and thus inbreeding is necessary for evolving pure line in any animal.
  • Inbreeding exposes the harmful recessive alleles, which become eliminated by selection.
  • Inbreeding also helps in the accumulation of superior genes and elimination of less desirable genes.
  • But, continued inbreeding causes inbreeding depression-that reduces vigour, fertility and even productivity.
  • Under such a situation, the selected animals of the breeding population are mated with unrelated superior animals of the same breed to restore fertility and yield.

(b) Outbreeding:

  • Outbreeding refers to the breeding of unrelated animals either of the same breed having no common ancestors for 4-6 generations (out crossing) or of different breeds (cross – breeding) or even different species (inter – specific).
  • Outbreeding is of the following types :

1. Outcrossing: Outcrossing is the practice of mating of animals of the same breed, but that have no common ancestors on either side of their pedigree upto 4-6 generations.

The offspring of outcrossing, is called an outcross.
A single outcross helps to overcome inbreeding depression.
It is the best breeding method for animals that are below average in productivity and growth rate.

2. Cross-breeding: It is a method of outbreeding in which superior males of one breed are mated with the superior females of another breed of the same species.

This helps in combining the desirable qualities of the two different breeds into the hybrid progeny.
The hybrid progeny may be directly used for commercial production or they may be subjected to some form of inbreeding and selection, to develop new stable breeds. One example of cross-breeding is Hisardale, a new breed of sheep developed by crossing Bikaneri ewes and Marino rams.

3. Interspecific hybridisation: It is a method of outbreeding in which male and female animals of two different species are crossed to combine the desirable features of both the parents into one, e.g.. Mule is produced by a cross between a male donkey and a female horse.

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