NCERT Solutions for Class 9 Science Chapter 15 Improvement In Food Resources

NCERT Solutions for Class 9 Science Chapter 15 Improvement In Food Resources


Class 9 Science NCERT Textbook Page 204

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

Answer:- We get carbohydrates which provide energy from cereals, proteins from pulses, and vitamins and minerals from fruits and vegetables.



Class 9 Science NCERT Textbook Page 205

Question:- 1. How do biotic and abiotic factors affect crop production?

Answer:- Insects, rodents, pests, and other biotic factors spread illness and reduce agricultural productivity.

Humidity, temperature, moisture, wind, rain, flood, and other abiotic factors all contribute to the destruction of the crop.


Question:- 2. What are the desirable agronomic characteristics for crop improvements?

Answer:- Tallness and profuse branching in any fodder crop and dwarfness in cereals are favourable agronomic qualities for crop improvement.




Class 9 Science NCERT Textbook Page 206

Question:- 1. What are macro-nutrients and why are they called macronutrients?

Answer:- Macronutrients are nutrients that are required in large amounts for plant growth and development. They are termed as macro-nutrients because they are required in huge quantities. Plants require six macronutrients: nitrogen, phosphorus, potassium, calcium, magnesium, and sulphur.


Question:- 2. How do plants get nutrients?

Answer:- Air, water, and soil are all sources of nutrients for plants. The plants requires 16 nutrients for growth . The main source of these nutrients is the soil. Thirteen of these nutrients can be found in the soil. Air and water provide the remaining three nutrients (carbon, oxygen, and hydrogen).




Class 9 Science NCERT Textbook Page 207

Question:- 1. Compare the use of manure and fertilizers in maintaining soil fertility.

Answer:- Effects of using manures on soil quality:

  1. The manures provide nutrients to the soil.
  2. They replenish the soil with organic matter (humus), restoring water retention capacity in sandy soils and drainage in clayey soils.
  3. Soil erosion is reduced when manures are used.
  4. They provide food for soil organisms, such as bacteria that are beneficial to the soil.

Effects of using fertilizers on soil quality:

  1. The soil gets powdery, dry, and the rate of soil erosion increases when fertilisers are used indefinitely.
  2. The usage of fertilisers reduces organic matter, which reduces soil porosity and prevents plant roots from receiving adequate oxygen.
  3. The soil becomes acidic or basic.




Class 9 Science NCERT Textbook Page 208

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:- (c) Farmers use quality seeds, adopt irrigation, use fertilizer and use crop protection measures.

It is not enough to use high-quality seeds unless they are properly irrigated, fertilised, and protected from biotic influences. As a result, option (c) will provide the most benefits.




Class 9 Science NCERT Textbook Page 209

Question:- 1. Why should preventive measures and biological control methods be preferred for protecting crops?

Answer:- Preventive measures and biological control methods are used for protecting crops and to eliminate diseases because they are easy, cost-effective,reduce pollution, and also increases productivity without harming soil quality.


Question:- 2. What factors may be responsible for losses of grains during storage?

Answer:- The following factors are responsible for grain losses during storage:

  1. Abiotic factors like moisture (present in food grains), humidity and temperature.
  2. Biotic factors like insects, rodents, birds, mites, bacteria and fungi.




Class 9 Science NCERT Textbook Page 210

Question:- 1. Which method is commonly used for improving cattle breeds and why?

Answer:- Crossbreeding is the most common approach for increasing the quality of cattle breeds. Because breeding two good cattle breeds leads in a new better variety of cattle breed or offspring.




Class 9 Science NCERT Textbook Page 211

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:- Poultry in India is the best converter of low fibre food stuff into highly nutritious animal protein food. In poultry farming, hens are raised to produce eggs and chicken. For this, they are given animal feeds in the form of roughage, which mainly consists of fibres. Thus, by feeding animals a fibre rich diet, the poultry gives highly nutritious food in the form of eggs and chicken.



Class 9 Science NCERT Textbook Page 211

Question:- 1. What management practices are common in dairy and poultry farming?

Answer:-  The most common management practices in dairy and poultry farming are following:-

  1. Well-designed Hygienic shelter.
  2. Good quality proper food and fodder are provided.
  3. protecting animal health by treating illnesses brought on by bacteria, viruses, or fungi.
  4. Sunlight feasible and airy ventilated shelter.



Question:- 2. What are the differences between broilers and layers and in their management?

Answer:- The hen that has been tamed to produce meat is known as a broiler. The hen that lays eggs is referred to as a layer.

Broilers have slightly different housing, dietary, and environmental needs than egg layers.

Broilers need a diet that is high in protein and has the right amount of fat. While layers need appropriate space and proper lighting, the amount of vitamins A and K is kept high in the chicken feed.




Class 9 Science NCERT Textbook Page 213

Question:- 1. How are fish obtained?

Answer:- There are two ways of obtaining fish. One is from natural resources, which is called capture fishing. The other method is cultural fishery, or fish farming.



Question:- 2. What are the advantages of composite fish culture?

Answer:- Fish can be cultivated in crop fields, especially rice, and intensive fish farming is possible since there is enough of water available throughout the crop-growing seasons. Both native and foreign fish species can be raised in this technique.




Class 9 Science NCERT Textbook Page 213

Question:- 1. What are the desirable characters of bee varieties suitable for honey production?

Answer:-  The desirable characters of bee varieties suitable for honey production are following:-

  1. The type of bee should be able to gather a significant quantity of honey.
  2. The bees need to remain in a particular beehive for a longer time.
  3. The bees should be able to reproduce successfully.
  4. The type of bee should be resistant to illness



Question:- 2. What is pasturage and how is it related to honey production?

Answer:- The flowers that are accessible to bees for nectar and pollen collection are referred to as pasturage. The taste of the honey will depend on the type of flowers that are available for pasturage.



Question:- 1. Explain any one method of crop production which ensures high yield.

Answer:- Intercropping is a technique for growing crops that guarantees a high yield. Growing two or more crops simultaneously is a common practise. in rows within the same field. A specific row pattern is followed when intercropping, such as one row of the main crop followed by two rows of the intercrop.

In intercropping, the interspaced area, light, nutrients, water, and air are used more effectively. Productivity per area unit rose as a result.


Question:- 2. Why are manure and fertilizers used in fields?

Answer:- In order to provide the necessary nutrients to the soil, manures and fertilizers are used in fields. Manure helps in adding organic matter and nutrients to the soil. This enhances the soil’s fertility and structure. On the other hand,  fertilizers guarantee that plants grow and develop in a healthy way. They are an excellent supplier of potassium, phosphate, and nitrogen. It is advised to employ a balanced combination of manures and fertilizers in the soil to achieve the best yield.


Question:- 3. What are the advantages of inter-cropping and crop rotation?

Answer:- Crop rotation and intercropping are both methods used to maximise the utilisation of limited land. Intercropping helps in limiting the spread of pests and illnesses across the entire field.

Crop rotation avoids soil depletion, reduces soil erosion, and increases soil fertility. It also increases soil fertility. Both of these methods reduce the need for fertilizers in field. They also helps in controlling weeds and the growth of pathogens and pests in crops.


Question:- 4. What is genetic manipulation? How is it useful in agricultural practices?

Answer:- Genetic manipulation is a process of incorporating desirable (genes) characters into crop varieties by hybridisation. Crossing between plants with different genetic compositions is known as hybridization.  This is done in order to produce varieties with desired traits, such as high producing kinds of maize and wheat and crops with plentiful branching for feed.

Genetic manipulation is useful in developing varieties which shows:

  1. Increased yield
  2. Better quality
  3. earlier and shorter maturation period
  4. Better adaptability to adverse environmental conditions
  5. Desirable characteristics


Question:- 5. How do storage grain losses occur?

Answer:- The storage grain losses occur due to the following reasons:-

  1. Abiotic factors like moisture (present in foodgrains), humidity (of air) and temperature.
  2. Biotic factors like insects, rodents, birds, mites and bacteria.


Question:- 6. How do good animal husbandry practices benefit farmers?

Answer:- Good animal husbandry practices are beneficial to the farmers in the following ways:


  1. breeding improvements for domesticated animals.
  2. raising the output of foods like milk, eggs, and meat.
  3. Use in agriculture for carting, irrigation and tilling
  4. Proper management of domestic animals in terms of shelter, feeding, care and protection against diseases. Which ultimately aids in the farmers’ improvement of their financial situation


Question:- 7. What are the benefits of cattle farming?

Answer:- Benefits of cattle farming are:

  1. Cattles are utilised in agriculture.
  2. creation of superior cattle
  3. purpose of milking and meat
  4. Cattle skin is utilised in the leather and wool industries.


Question:- 8. For increasing production, what is common in poultry, fisheries and bee-keeping?

Answer:- Cross breeding techniques are utilised in fisheries, beekeeping, and poultry to increase productivity. Along with these techniques, routine maintenance procedures help to increase production.


Question:- 9. How do you differentiate between capture fishing, mariculture and aquaculture?

Answer:- Capture fishing: It is a technique in which fishes are captured from various sources of natural resources like sea, rives, lake and pond.


Mariculture: Mariculture is the practise of raising fish in maritime environments for commercial purposes, including mullets, prawns, oysters, and bhetki.


Aquaculture: Fish are cultured in both fresh and salt water through aquaculture.