Utility of such plants is due to:
(i) Rapid multiplication rate
(ii) To get uniformity in crop yield.
(iii) A better variety once developed, continues to remain with same characters without loosing vigour.

Animal husbandry:
(i) The ever increasing demand  for food from animals and animal products, both in terms of quality and quantity has been met by animal husbandry practies.
(ii) There has been a remarkable growth in the practicle of bee-keeping  and production of honey
(iii) Demand for aquatic foods, espectively fish and fish products has also been met by animal husbendry practices.

(a) Mutations can be induced by
(i) use of chemicals or
(ii) use of radiation like gamma radiation.
(b) After inducing mutations, there are two steps:
(i) Selection of plants that have describle character as a source for breeding and
(ii) Hybridisation of the selected plants.

Apis indica is the most common species.Advantages of keeping beehives in crop fields during floering season:
(i)Since it increases pollination efficiency,the yield of crop improves,
(ii) Honey collection also increases.

The method of breeding crops with higher levels of vitamins and minerals or higher protein and healthier fats is called biofortification. It is one the most important method for improving public health. During recent past, many varieties of crop plants such as rice, carrots, spinach, pumpkin, bathua have been developed which possess several times more nutritive value and vitamins as compared to existing varieties.

Totipotency is defined as the capacity of any cell to generate. the whole plant from it.Requirements:
(i) Explant
Any part of a plant taken out for growing a new plant in special nutrient medium, under sterile/ aseptic conditions.
(ii) Nutrient medium
The nutrient medium must provide a carbon source such as sucrose,

Blue revolution is a movement lanched to increase the production of fish.Freshwater fish: catla and Rohu. Marine water fish: Helsa and sardines.

Totipotency is the property by which each plant cell can grow into a new plant.
Advantages of micropropagation are as follows:
(i) By this method, thousands of plants can be raised in a short duration.
(ii) By culturing the meristems of even virus-infected plants, virus-free (healthy) plants can be raised.
(iii) Since the plants ar/ genetically identical, certain desirable characters can be continued through generations.
(iv) Through somatic hybridisation, hybrids which otherwise cannot be produced, can be raised.

(a) Multiple ovulation Embryo Transfer , (MOET) technology
(b) Steps in MOET technology:
1. A cow is administered hormones with FSH-like activity to induce follicular maturation and superovulation, i.e. instead of one egg, 6-8 eggs are produced per cycle.
2. The animal is either mated with an elite bull or artificially inseminated.
3. The fertilised eggs are recovered at the 8-32 celled stages, nonsurgically.
4. They are then transferred to surrogate mothers.
5. The genetic mother is available for and her round of superovulation.

Common diseases of fishes
1. Main infectious disease of fishes are:
(a) Viral Haemorrhagic Septicemia (VHS) and (b) Bacterial Infectious Pancreatic Necrosis (IPN).
2. Water-pollution caused disease of fishes are:
(a) Gill rot (Blackening of gills).
(b) Fin rot (Cutting down of fins).
(c) Dropsy (Swollen belly).
3. Fish-ectoparasites - e.g., fish lice - Argulus.
Control of fish-diseases
(i) Pollution of fish-farm should be avoided.
(ii) Regular monitoring of the level of oxygen, carbon dioxide and pH of the water of fish-form.
(iii) Argulus-fish lice can be controlled by adding 2.5 ml/litre of Malathion in the pond water.

Prevention of common diseases. Some of the imporatant steps for preventing animal diseases are:
1. The animal shelters should be spacious, airy and properly lighted.
2. The animal shelters should be cleaned regularly.
3. A good and nutritive feed and uncontaminated water should be provided to the animals.
4. Animals should be given regular bathing and grooming to avoid the infections.
5. The animals should be compulsorily vaccinated to immunise them against infectious diseases.
6. Lice, ticks and other external parasites of animals should be controlled by the use of insecticides.
7. The pests should not be allowed to enter their shelters.
8. Proper disposal of dead animals and animal wastes.
9. Hygienic handling of all animal products and by-products.

(A) Role of modern methods of breeding animals:
(i) By continued inbreeding, superior genes can be accumulated and less desirable genes can be eliminated by selection. It is also used to produce pure line.
(ii) By cross-breeding, good characters of different breeds can be combined to produce high yielding hybrid animals Examples 1.Karan Swiss breed of Switzerland and Sahiwal of India and gives about 3,500 litres of milk during its lactation period of 300 days.
2. High yielding layers of fowls e.g. IBL-80; B-77 and HH-260 are also cross-breeds out of which IBL-80 and B-77 breeds produce 200 eggs while HH-260 produces 260 eggs in a year.
3. Hissardale is a high wool and meat-yielding cross breed of sheep, while mules are more sturdier and stronger interspecific hybrids produced by a cross between male donkey and female horse (mare).
(iii) Multiple Ovulation-Embryo Transfer (MOET):
(iv) Artificial Insemination 
(B)Role of modern methods of plant breeding:
1. Green revolution.
2. Genetically modified crops.