Chapter 12: Improvement in Food Resources
Question with Answer
Page 141
Question 1.
What do we get from cereals, pulses, fruits and vegetables?
Answer:
-
Cereals provide carbohydrates, which give energy.
-
Pulses provide proteins, which are needed for growth and repair of the body.
-
Fruits and vegetables provide vitamins and minerals, which protect us from diseases and keep the body healthy.
Page 142
Question 1
How do biotic and abiotic factors affect crop production?
Answer:
-
Biotic factors such as insects, pests, diseases, weeds and pathogens damage crop plants and reduce their yield.
-
Abiotic factors such as drought, salinity, waterlogging, heat, cold and frost affect the growth and productivity of crops.
Thus, both biotic and abiotic factors reduce crop production by affecting plant health and growth.
Question 2
What are the desirable agronomic characteristics for crop improvements?
Answer:
Desirable agronomic characteristics for crop improvement include:
-
Tallness and profuse branching in fodder crops to obtain more biomass
-
Dwarfness in cereal crops so that less nutrients are used and lodging is prevented
These characteristics help in obtaining higher yield and better productivity.
Page 143
Question 1
What are macro-nutrients and why are they called macro-nutrients?
Answer:
Macro-nutrients are nutrients that are required by plants in large quantities for their growth and development.
They are called macro-nutrients because plants need them in comparatively large amounts.
Examples of macro-nutrients are nitrogen, phosphorus, potassium, calcium, magnesium and sulphur.
Question 2
How do plants get nutrients?
Answer:
Plants get nutrients in the following ways:
-
Carbon and oxygen are obtained from air.
-
Hydrogen is obtained from water.
-
Other nutrients are obtained from the soil in dissolved form through the roots.
These nutrients are then used by plants for growth and development.
Page 144
Question 1
Compare the use of manure and fertilizers in maintaining soil fertility.
Answer:
| Manure | Fertilizers |
|---|---|
| Manure is a natural substance obtained by the decomposition of plant and animal wastes |
Fertilizers are chemical substances manufactured in factories |
| It supplies nutrients in small quantities |
It supplies nutrients in large quantities |
| It adds organic matter to the soil |
It does not add organic matter to the soil |
|
It improves soil structure, water-holding capacity and aeration |
It does not improve soil structure |
| It increases soil fertility in the long term |
Continuous use may reduce soil fertility |
Page 145
Question 1
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.
Answer:
Option (c) will give the most benefits.
Explanation:
Quality seeds ensure better yield potential.
Irrigation supplies adequate water at different stages of crop growth.
Fertilizers provide essential nutrients required for healthy plant growth.
Crop protection measures protect crops from weeds, pests and diseases.
Thus, the combined use of quality seeds, irrigation, fertilizers and crop protection results in maximum yield and better crop production.
Page 146
Question 1
Why should preventive measures and biological control methods be preferred for protecting crops?
Answer:
Preventive measures and biological control methods should be preferred because:
-
They do not cause environmental pollution.
-
They do not harm useful organisms present in the ecosystem.
-
They help in maintaining ecological balance.
-
They reduce the harmful effects caused by excessive use of chemical pesticides.
Question 2
What factors may be responsible for losses of grains during storage?
Answer:
Losses of grains during storage occur due to the following factors:
-
Biotic factors: insects, rodents, fungi, mites and bacteria
-
Abiotic factors: improper moisture and unsuitable temperature conditions
These factors lead to loss in weight, quality and germination capacity of stored grains.
Page 147
Question 1
Which method is commonly used for improving cattle breeds and why?
Answer:
The commonly used method for improving cattle breeds is cross-breeding.
Explanation:
Cross-breeding is done between indigenous breeds (which have good disease resistance) and exotic breeds (which have high milk yield and long lactation period).
This helps in obtaining cattle with both high milk production and disease resistance.
Page 148
Set – 1
Question 1
Discuss the implications of the following statement:
“It is interesting to note that poultry is India’s most efficient converter of low-fibre food stuff (which is unfit for human consumption) into highly nutritious animal protein food.”
Answer:
The statement highlights the importance and efficiency of poultry farming in food production.
Explanation:
-
Poultry birds can consume low-fibre agricultural by-products such as broken grains and crop residues, which are not suitable for direct human consumption.
-
These low-quality food materials are efficiently converted into high-quality animal protein in the form of eggs and meat.
-
Poultry farming requires less space, less time and lower investment compared to other animal husbandry practices.
-
It helps in reducing food wastage and provides a cheap and rich source of protein to humans.
-
Thus, poultry farming plays an important role in nutritional security and income generation.
Hence, poultry is an efficient system for converting low-value feed into nutritious food for humans.
Set – 2
Question 1
What management practices are common in dairy and poultry farming?
Answer:
The common management practices in both dairy and poultry farming are:
-
Proper housing and shelter
-
Balanced and nutritious feed
-
Cleanliness and sanitation
-
Prevention and control of diseases through vaccination
Question 2
What are the differences between broilers and layers and in their management?
Answer:
| Broilers | Layers |
|---|---|
| Raised for meat production | Raised for egg production |
| Require protein-rich diet with more fat |
Require balanced diet rich in vitamins and minerals |
| Short growth period | Longer rearing period |
| Management focuses on rapid growth |
Management focuses on egg laying capacity |
Page 150
Set – 1
Question 1
How are fish obtained?
Answer:
Fish are obtained in two ways:
-
Capture fishing: Fish are caught from natural water bodies such as seas, rivers, lakes and ponds.
-
Culture fishery (fish farming): Fish are bred and reared in controlled water bodies like ponds, tanks and reservoirs.
Question 2
What are the advantages of composite fish culture?
Answer:
The advantages of composite fish culture are:
-
Different species of fish having different food habits are grown together.
-
Fish use food from all levels of the pond (surface, middle and bottom).
-
There is no competition for food among fish species.
-
It results in higher fish yield from the same pond.
Set – 2
Question 1
What are the desirable characters of bee varieties suitable for honey production?
Answer:
Desirable characters of bee varieties suitable for honey production are:
-
High honey collection capacity
-
Less aggressive nature (sting less)
-
Ability to stay in the hive for long periods
-
Good breeding capacity
-
Resistance to diseases
These characteristics help in obtaining higher yield of honey.
Question 2
What is pasturage and how is it related to honey production?
Answer:
Pasturage refers to the availability of flowers from which bees collect nectar and pollen.
Relation to honey production:
-
The quantity of honey depends on the abundance of flowers available.
-
The quality and taste of honey depend on the type of flowers present in the pasturage.
Thus, good pasturage results in better quality and higher production of honey.