Improvement in food resources

                                                          Class-IX                                                   Biology

1.    What do we get from cereals, pulses, fruits and vegetables?

Ans- Cereals provide carbohydrates.

         Pulses provide proteins.

         Fruits provide vitamins, minerals and sugars (glucose/fructose).

          Vegetables provide vitamins, minerals, fibers and carbohydrates.

2.    How do biotic and abiotic factors adverse affect crop production?

Ans- a. Biotic factors:

          i. Cattle, rodents and insects feed on standing crop and destroy either crop plants or their produce.

         ii. Nematodes, bacteria, viruses and fungi destroy crop by causing various diseases.

           b. Abiotic factors: Drought, water- logging, cold, frost, hailstorm, day length, acidity or alkalinity of soil, etc, influence growth and flowering in plants.

3.    What are desired agronomic characteristics for crop improvement?

Ans- Agronomic features:

a.     For cereals plants: short in height, profuse branching and short maturation period.

b.     For legume crops: Extensive branching for bearing more pods and more foliage.

c.      For fodder crops: tall plants with intensive branching, good foliage and juicy stem.

4.    What are macronutrients and why are they called macronutrients?

Ans- Macronutrients are essential inorganic elements required by plants in relatively large quantities for growth and reproduction. They are called macronutrients because they ate required in relatively large quantities,    e.g., Carbon, Hydrogen, Oxygen, nitrogen, phosphorus, potassium, calcium, etc.

5.    How do plants get nutrients?

Ans- Plant get nutrients from air, water and soil. Carbon and oxygen are obtained from air, hydrogen from water and remaining 13 essential elements Nitrogen , phosphorous, potassium, calcium, Magnesium , Sulphur, Iron, Manganese, Boron, zinc, copper, Molybdenum and chlorine from soil through absorption along with water.

6.    Compare the use of manure and fertilizers in maintaining soil fertility.

Ans- Manure contains organic substances. It is degraded and absorbed easily by plants. It increases and prolongs the fertility of soil without causing any harm. However, manure contains small quantity of minerals salts and is not nutrients –specific.

The chemical fertilizers, on the other hand, contain nutrients in considerable amount but improve the soil fertility for a short duration. Continuous use of fertilizers destroys the natural soil fertility potential and also degrades the environment.

7.    Why should preventive measures and biological control methods be preferred for protecting crops?

Ans- Both preventive and biological control methods are preferred for protecting crops because:

a.     They are environment friendly.   c. They are target- specific.

b.     They do not cause pollution.        d. They are harmless to other life forms.

8.    What factors may be responsible for loss of grains during storage?

Ans- Factor responsible for the loss of stored grains are both abiotic and biotic.

Abiotic factors include improper temperature of store house, humidity of air and high moisture content of the grains. Improper containers for storage also cause loss of grains.

Biotic factors include infestation of insects; infestation with mites, birds, rodents; diseases caused by microorganisms and enzymes action that occur within stored food grains.

9.    Which method is commonly used for improving cattle breeds and why?

Ans- Cattle breeds are improved by cross breeding between indigenous breed and exotic breeds. The indigenous breeds are hardy and resistant to several diseases, and exotic breeds have high- milk yield and longer lactation period. The progeny resulting from cross breeding contains the desirable traits of both the breeds.

10. Discuss the implication of the following statement:

“It is interesting to note that poultry is India’s most efficient converter of low fiber food stuff (which is unfit for human consumption) into highly nutritious animal protein food.”

Ans- The agriculture wastes produced during food processing, e.g. rice bran, fish meal, oil cakes are unfit for human consumption. These are utilized as poultry feed. Poultry birds effectively convert these substances into highly nutritious eggs and meat rich in animal protein.

11. What management practice is common in dairy and poultry farming?

Ans- The common management practices adopted in dairy and poultry farming are:

a.     Providing shelter, rich feed and clean drinking water.

b.     Maintain optimum temperature and good hygienic conditions in farmhouse and poultry farm.

c.      Providing health care and timely vaccination to farm animals.

12. What are the differences between broilers and layers and their management?

Ans- Broilers are young chickens of 6-10 weeks of age. They grow fast and are used as meat which is of good quality and good taste. The layers are sexually mature hens which are raised to lay eggs.

Management: Broilers are given protein – rich food with adequate amount of fat and vitamins. They are provided good space, adequate temperature and best of the hygiene. The layers are given comparatively poor quality of feed. Temperature regulation is not required but they are given plenty of light.

13. Explain any one method of crop production which ensures high yield.

Ans- To increases crop production, various agricultural practices like mixed cropping, intercropping, crop rotation hybridization, etc. are in use. If same crop is grown year after year, it creates deficiency of certain nutrients in the soil and soil loses its fertility. Crop rotation helps in restoring fertility. It involves growing different types of crops on the same piece of land in a specific succession. Crops chosen are such that when one withdraws nutrients from soil, the other crop replenishes them. If crop rotation is done properly, two or three crops can be grown in a year with good yield.

14. Why are manures and fertilizers used in fields?

Ans- Manures and fertilizers are added to enhance and enrich the soil with both organic and inorganic nutrients. Manures also provide porosity to the soil, increase its water retention and enhance activity of microorganisms.

15. What are the advantages of intercropping and crop rotation?

Ans- Intercropping:

1.     Intercropping ensures greater crop yield.

2.     It helps in better utilization of natural resources (land, water, nutrients and sunlight).

3.     It prevents soil erosion.

4.     Each crop can be harvested threshed and marketed separately at different times.

5.     Since different crops are sown in separate rows and mature at different times, there is no mixing of produce of these crops.

6.     Intercropping saves time and labor of the farmer.

Crop rotation:

1.     The soil fertility is maintained for longer period.

2.     The chemical nature of soil is not altered.

3.     It helps in weed and pest control through breaking the cycle by rotation of crop variety.

4.     Crop rotation saves a lot of nitrogen fertilizer and land is not left free of cultivation. As a result, 2-4 crops are raised per year. This increases income of farmers.

16. What is genetic manipulation? How is it useful in agricultural practices?

Ans- Genetic manipulation is transfer of one or more desirable genes from    one plant of same or other species or variety to another. The transfer of gene may be carried out by cross breeding, mutation breeding or recombinant DNA technology. Through genetic manipulation, high yielding and disease resistant crop varieties can be produced.

17. How do storage grains losses occur?

Ans- Losses of stored grains may occur due to a) high moisture content of grains and increased humidity in air provide suitable environment for the growth of microorganisms which in turn disintegrate the food grains . b) Insects pests and enzymatic activity also damages stored grains leading to their loss. c) Rodents, birds feed on grains. d) Weevils, Pulse borers, Khapra beetles also damage by boring or feeding on stored grains.

18. How do good animal husbandry practices benefit farmers?

Ans- Good animal husbandry practices benefit farmers by:

a.     Good hygiene protects cattle and other animals from infectious diseases.

b.     Clean and spacious shelter keeps animals healthy.

c.      Proper healthy diet enhances growth and yield of livestock.

d.     Segregation of sick animals protects other livestock.

e.     Vaccination prevents and protects young animal products like milk, eggs and meat.

f.       Prevents loss of livestock due to diseases.

19. What are the benefits of cattle farming?

Ans- a. farming of milk animal, such as cow, buffalo, goat and camel provide us with milk and milk byproducts like ghee, butter, paneer, etc. Use of exotic and hybrid varieties has resulted in White revolution.

        b. Farming of draught animals, such as bullocks provide animals for agricultural purposes, such as tilling, irrigation and transport of food grains.

        c. Growing fodder for cattle enriches soil.

        d. Organic waste generated by cattle farming can be used for manure.

        e. It provides extra income.

20. For increasing production, what is common in poultry, fisheries and bee-keeping?

Ans- The common features among poultry, fisheries and bee-keeping are:

a)     Good quality of breeds.

b)    Good, nutritious food.

c)     Proper clean, airy and well-lighted accommodation.

d)    Proper medical and health care to control diseases.

21. How do you differentiate capture fishing, mariculture and aquaculture?

Ans- Capture fishing

a.     In capture fishing, the fishes are collected from various natural sources such as rivers, ponds, lakes and seas.

b.     No seeding or rearing of fish is required.

  Mariculture

a.     In mariculture, the marine fishes, shellfishes and sea weeds are cultured in coastal water.

b.     Fish and other organisms are seeded and reared.

Aquaculture

a.     In aquaculture, economically important freshwater plants and animals, including fishes, are cultured in freshwater reservoirs.

b.     Fish and other organisms are seeded and reared.