NCERT Solutions for Class 9 Chapter 15 Improvement in Food Resources
1. What do we get from cereals, pulses, fruits and vegetables?
Solution:
Cereals are the source of carbohydrate and is main reason of energy.
Pulses provide protein for growth and development
Vegetables and fruits are loaded with minerals, vitamins, carbohydrates, proteins and fats for overall development.
2. How do biotic and abiotic factors affect crop production?
Solution:
2 major factors that affect the crop are:
- Biotic factors like insects, rodents, pests, and many more spread the disease and reduce crop production.
- Abiotic factors like humidity, temperature, moisture, wind, rain, flood and many more destroy the crop raised.
3. What are the desirable agronomic characteristics for crop improvement?
Solution:
The essential agronomic features required for crop improvement are:
- Profuse branching along with tallness in any fodder crop
- Dwarfness in any cereals.
4. What are macro-nutrients and why are they called macronutrients?
Solution:
Macro-nutrients are the fundamental elements that are used by plants in more quantity. Macro-nutrients needed by the plants are:
• Macro-nutrients as the constituent of protoplasm
• Phosphorus, Nitrogen, Sulphur are present in proteins
• Calcium is existing in cell wall
• Magnesium is significant component of chlorophyll
5. How do plants get nutrients?
Solution:
There are 16 basic essential nutrients required by the plants to grow. Carbon and Oxygen are supplied by water and the remaining nutrients are supplied through soil.
6. Compare the use of manure and fertilizers in maintaining soil fertility.
Solution:
- Manure improves the soil quality with added nutrients.
- Manure provides extra organic matter called humus to the soil and therefore increasing the water retention capacity of sandy soils and drainage in clayey soil.
- Manures reduces soil erosion.
- They provide food for soil friendly bacteria which are helpful in growing crops.
Effects of fertilizers are:
- Fertilizers make the soil to become too dry and powdered and rises rate of soil erosion.
- The organic matter decreases by decreasing the porosity of soil hence, the plant roots do not get oxygen properly.
- The nature of soil changes either to basic or acidic.
7. Which of the following conditions will give the most benefits? Why?
(a) Farmers use high-quality seeds, do not adopt irrigation or use fertilizers.
(b) Farmers use ordinary seeds, adopt irrigation and use fertilizer.
(c) Farmers use quality seeds, adopt irrigation, use fertilizer and use crop protection measures.
Solution:
Option (c) will give the most benefits because use of good quality seeds is not only sufficient until the soil is properly irrigated, enriched with fertilizers and protected from biotic factors.
8. Why should preventive measures and biological control methods be preferred for protecting crops?
Solution:
Over exposure of chemicals leads to environmental problems hence, biological methods are preferred for protecting crops from pathogens, insects and rodents along with increasing the production. Since chemicals are harmful for plants and also for the animals which feed on it, hence bio-pesticides are used as the safe way of crop protection.
9. What factors may be responsible for losses of grains during storage?
Solution:
Biotic and Abiotic factors are responsible for loss of grains during storage like:
- Rodents
- Pests
- Insects
- Fungi
- Bacteria
- Sunlight
- Flood
- Rain
- Temperature
- Moisture
10. Which method is commonly used for improving cattle breeds and why?
Solution:
Cross breading is generally the best method adopted for improving the cattle breed quality. In this method, breeding is between two good cattle breed results in a new improved variety of cattle breed or offspring. While breeding, care is taken to have a good resultant with high yield having resistance to climatic conditions.
11. What management practices are common in dairy and poultry farming?
Solution:
- Well-designed Hygienic shelter for dairy animals and poultry birds.
- Good quality proper food and fodder are provided to dairy animals and poultry birds.
- Importance for animal health by prevention and cure of disease caused by bacteria, virus, or fungi.
- Sunlight feasible and airy ventilated shelter for animals
12. What are the differences between broilers and layers and in their management?
Solution:
Broilers:
The poultry bird raised for meat purpose is called broiler. Broilers feed on protein rich adequate fat food. The level of vitamins A and K is kept high in the poultry feeds.
Layers:
The egg laying poultry bird is called layer. The housing, environmental and nutritional requirements of broilers vary from those of egg layers. Layers require proper lightning and enough space.
13. Discuss the implications 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.”
Solution:
Poultry farming aims in raising domestic birds for egg and chicken meat purpose. These domestic birds feed on animal feeds which mainly consists of roughages for getting good quality feathers, egg, chicken and nutrient rich manure. For this reasons, it is said that, “poultry is India’s most efficient converter of low fibre food stuff into highly nutritious animal protein food”.
14. How are fish obtained?
Solution:
Fishes are obtained in two ways:
Capture fishing: obtaining fishes from natural resources
Culture Fishery: culturing of fishes in freshwater ecosystem like river, pond and lake also including marine.
15. What are the advantages of composite fish culture?
Solution:
Advantages of composite fish culture are:
- In a single fish pond, a combination of 5 or 6 types of fish species can be cultured since they do not compete for food among them.
- Food resource can be completely utilized
- Survival of the fish also increases
- More yield
