Plant and Animal Breeding–10th Science Notes and Question Bank

CHAPTER-19

Plant and Animal Breeding

Text Book Question and Answers

I. Answer the following

1. What are crop plants? How are they classified? Give two examples for each of them.

plants which are grown and cared in the fields to serve as food or as a source of any food product, and harvested seasonally are called crop plants

Food crops are classified into two types based on the season of cultivation or harvesting, namely;

(a) Kharif crops:- They are raised in rainy seasons and harvested at the end of monsoon season.

Ex:- Wheat

(b) Rabi Crops:- They are raised in winter season and harvested in the summer.

Ex:- Paddy.

2. What is hybridization? Mention it's different types.

The process of crossing of two plants which differ in on or more characters to produce hybrid is called hybridization.

The different types of hybridization are:-

a) Interrarietal hybridization

b) Interspecific hybridization

c) Intergenetic hybridization

3. What is polyploidy? What is it's importance.

The technique of increasing the number of chromosomes from diploid set to multiple set of chromosomes is called ployploidy.

Polyploid plants are bigger in size and show greater genetic variability.

4. What is induced mutation? How is it caused?

The technique of changing the genotype of plants is called induced mutation

It is caused by radiations or by certain chemicals.

5. What is tissue culture? what are its advantages?

The technique of growing an entire plant from a single cell or a tissue under aseptic laboratory conditions id called tissue culture.

Tissue culture Advantages are:-

a) Tissue culture is extensively used for large scale propagation of medicinal and ornamental plants.

b) Tissue culture is also used for propagating crop and forest plants

c) Tissue culture is also used for developing disease – free plants

d) Tissue culture is used particularly, for the extraction of many useful metabolites.

6. What are transgenic plants? What are their relative merits and demerits?

A specific gene responsible for a desired trait, is selected and introduced directly into the new plant variety. This is called genetic modification and such plants are called transgenic plants.

The socio – economic impacts and distributions of benefits from transgene has been stimulated on the merits and demerits of genetic engineering of crop plants and that serious damage can be done to the cellular tissue.

7. What is hydroponics? Make a list of its advantages.

A practice of growing plants in mineral nutrient solutions in water, without soil is called hydroponics

Advantages are:-

a) Soil is not required

b) Water requirement is very less

c) Yields are stable and high.

d) There will be no weeds to remove.

e) Plants grow much healthier.

8. What are the advantages of roof-top gardening? What precautions are necessary for this method?

Advantages:-

a) It increases access to safe outdoor green space.

b) It improves air quality due to increased absorption of carbon dioxide.

c) It becomes a source of reaction

d) It encourage urban food production

Precautions:-

a) Roof should be prevented from becoming leaky due to seepage of water

b) Roof should be able to bear the additional weight of plants and soil.

9. What is livestock? How are they grouped? Give an example for each

The term livestock is used to collectively describe animals domesticated by man for various uses.

On the basis of their utility, livestock can be grouped as follows:-

a) Milk yielding animals – Cow

b) Meat and egg yielding animals – Fowl

c) Animals for agriculture and transportation – Bullocks.

d) Wood and leather yielding animals – Sheep

e) Honey, Silk and lac yielding – Honey bee, Silk worm, Lac insect.

10. Mention the three kinds of breeds of cows in India with two examples for each.

a) Indigenous breeds – Sindhi, Sahiwal

b) Exotic breeds – Jersey, Holstein

c) Cross breeds – Karan Swiss, Karan fries

11. What are transgenic animals? Give two examples.

The animals containing foreign genes from different species are called transgenic animals.

Ex:- cattle, goat, sheep.

12. What are food additives? How are they classified?

The substances used to increase the shelf life and nature of food are called food additives.

They are classified as Natural additives, Manmade additives, Artificial additives, Antioxidants, Colorants, Flavour ants and sweeteners.

II. Name the following.

1. A chemical, used to induce polyploidy

Colchicine

2. Agents that cause genetic changes.

Matagenas

3. Technique used to obtain genetically modified plants.

Recombinant DNA Technology

4. Carrier gene used to transfer the desired gene into a new host cell.

Vector DNA

5. Substances used to improve the nature of food with an increase in it's shelf life.

Food Additives

6. Food additives used to prevent the spoilage of food.

Preservatives

7. Capacity of cell to differentiate into new organism.

Totipotency

III. Differentiate between.

1. KHARIF CROPS AND RABI CROPS

Kharif crops	Rabi crops
i. raised in rainy season	i. raised in winter
ii. Harvested at the end of monsoon	ii. Harvested in the summer

2. INTER SPECIFIC HYBRIDISATION AND INTERGENERIC HYBRIDISATION

Inter specific hybridization

Inter generic hybridization

i. Crossing is done between two related species

of same genus.

i. Crossing is done between two plants of

related genera.

3. MUTANT AND MUTAGEN

MUTANT	MUTAGEN
i. The plant produced as a result of mutation.	i. The chemical agent which induces a mutation.

4. HYDROPONICS AND AEROPONICS

HYDROPONICS

AEROPONICS

i. Growing plants in mineral nutrient

solution in water without soil.

i. Growing plants where the roots of a plant are

either continuously or discontinuously kept in

an environment saturated with fine drops of

mineral nutrients.

5. INBREEDING AND OUTCROSSING

INBREEDING

OUT CROSSING

i. Crossing of the male and female

individuals of same species, among same

breeds.

i. Crossing of superior male of one breed

with superior female of another breed

of same species.

6. ANTIOXIDANT AND COLOURANT

ANTIOXIDANT

COLOURANT

i. Prevent food from developing fowl

smell

i. Restore colour lost during processing

of food or add a new colour.

IV. Give reasons for the following.

1. Hydroponic and aeroponic methods are important for space research organizations.

Hydroponic and aeroponic methods are of significance for space research organizations, in developing special kinds of food are astronauts. It is because a mist is easier to handle in zero-gravity situations, than a liquid. Hence, these two fields are gaming significance in developing space foods.

2. Food additives are widely used in modern life.

Food additives play a major role in increasing the shelf life and nature of food.

3. Polyploids have both advantages and limitations.

Polyploid plants are bigger in size and show greater genetic variability but in these plants fertility is lower and growth is very slow. therefore it has both advantages and limitations.

4. Addition of artificial food additives should be minimized.

The usage of artificial food additives may cause health problems. Therefore addition of artificial food additives should be minimized.

ADDITIONAL QUESTIONS

I. Fill in the blanks:

1. Rabi crops are raised and harvested during the seasons winter and summer

2. Triticale is a new variety of plant produced by cross breeding of wheat plant and rye plant

3. Paddy is a cereal

4. Commonly used technique in plant breeding is hybridization

5. A good example for transgenic plant among the following

a. Bt cotton b. Silver cotton c. Money plant d. White sugar cane

II. Answer the following questions:

1. Classify the following crop plants under different crop types like- pulses,cereals, spices, beverages, oil crop Tea, sesame, jowar, Bengal gram, oats, cocoa, French beans,

cardamom, soya bean, cumins

Tea, cocoa – Beverages

Sesame, soya bean- oil crops

Bengal gram, French beans – pulses

Jowar, oats – cereals

Cardamom, cumin – Spices

2. What is the purpose of crossing two plants in conventional breeding?

The aim of crossing two closely related plants is to combine the favourable traits from both the plants and eliminate their unwanted traits.

3. What are qualitative improvements brought in the following ‘genetically modified plants?

a. Bt cotton

b. Golden rice

c. Water melon