15. Improvement in Food Resources Class 9 NCERT Exemplar Solutions Chapter 15 (CBSE Science)

CBSE Class 9 Science Chapter 15 : Improvement in Food Resources – NCERT Exemplar Questions with Answers

Chapter 15: Improvement in Food Resources

Multiple Choice Questions

1. Which one is an oil yielding plant among the following ?

(a) Lentil       (b) Sunflower     (c) Cauliflower     (d) Hibiscus

Answer: (b) Sunflower

[ Sunflower seeds contain a large amount of oil and are commonly used to produce edible sunflower oil, so it is an oil-yielding plant. ]

2. Which one is not a source of carbohydrate?

(a) Rice       (b) Millets       (c) Sorghum     (d) Gram

Answer: (d) Gram
[ Gram mainly provides protein, not carbohydrates, while rice, millets and sorghum are rich sources of carbohydrates.]

3. Find out the wrong statement from the following

(a) White revolution is meant for increase in milk production

(b) Blue revolution is meant for increase in fish production

(c) Increasing food production without compromising with environmental quality is called as sustainable agriculture

(d) None of the above

Answer:  (d) None of the above

[ All statements are correct: White revolution—milk, Blue revolution—fish production and sustainable agriculture means increasing food without harming the environment.]

4. To solve the food problem of the country, which among the following is necessary?

(a) Increased production and storage of food grains

(b) Easy access of people to the food grain

(c) People should have money to purchase the grains

(d) All of the above

Answer: (d) All of the above

[ Solving food problems needs higher production and storage, proper distribution and people must have enough money to buy food grains. ]

5. Find out the correct sentence

(i) Hybridisation means crossing between genetically dissimilar plants

(ii) Cross between two varieties is called as inter specific hybridisation

(iii) Introducing genes of desired character into a plant gives genetically modified crop

(iv) Cross between plants of two species is called as inter varietal hybridisation

(a) (i) and (iii)          (b) (ii) and (iv)          (c) (ii) and (iii)         (d) (iii) and (iv)

Answer: (a) (i) and (iii)

[ Hybridisation is crossing genetically dissimilar plants. Genetically modified crops are produced by introducing desired genes into plants.]

6. Weeds affect the crop plants by

(a) killing of plants in field before they grow

(b) dominating the plants to grow

(c) competing for various resources of crops (plants) causing low availability of nutrients

(d) all of the above.

Answer: (c) competing for various resources of crops (plants) causing low availability of nutrients.
[ Weeds compete with crop plants for nutrients, water, sunlight and space, reducing the availability of resources for crops. ]

7. Which one of the following species of honey bee is an Italian species?

(a) Apis dorsata      (b) Apis florae    (c) Apis cerana indica     (d) Apis mellifera

Answer:  (d) Apis mellifera

[ Apis mellifera is the Italian honey bee species. It is commonly used in beekeeping because it produces more honey and is less aggressive. ]

8. Find out the correct sentence about manure

(i) Manure contains large quantities of organic matter and small quantities of nutrients.

(ii) It increases the water holding capacity of sandy soil.

(iii) It helps in draining out of excess of water from clayey soil.

(iv) Its excessive use pollutes environment because it is made of animal excretory waste.

(a) (i) and (iii)      (b) (i) and (ii)       (c) (ii) and (iii)     (d) (iii) and (iv)

Answer:  (b) (i) and (ii)

[ Manure contains more organic matter with fewer nutrients and increases the water-holding capacity of sandy soil. Excess use does not cause pollution like chemical fertilisers.]

9. Cattle husbandry is done for the following purposes

(i) Milk Production       (ii) Agricultural work      (iii) Meat production     (iv) Egg production

(a) (i), (ii) and (iii)      (b) (ii), (iii) and (iv)          (c) (iii) and (iv)          (d) (i) and (iv)

Answer:  (a) (i), (ii) and (iii)

[ Cattle are reared for milk production, agricultural work like ploughing, and meat. Eggs are produced by poultry, not cattle. ]

10. Which of the following are Indian cattle?

(i) Bos indicus      (ii) Bos domestica      (iii) Bos bubalis     (iv) Bos vulgaris

(a) (i) and (iii)      (b) (i) and (ii)      (c) (ii) and (iii)      (d) (iii) and (iv)

Answer:  (a) (i) and (iii)

[ Bos indicus (Indian cow) and Bos bubalis (Indian buffalo) are common Indian cattle breeds used in agriculture and milk production. ]

11. Which of the following are exotic breeds?

(i) Brawn       (ii) Jersey        (iii) Brown Swiss    (iv) Jersey Swiss

(a) (i) and (iii)        (b) (ii) and (iii)          (c) (i) and (iv)         (d) (ii) and (iv)

Answer: (b) (ii) and (iii)

[ Jersey and Brown Swiss are exotic cattle breeds from foreign countries, commonly used for high milk production.]

12. Poultry farming is undertaken to raise following

(i) Egg production        (ii) Feather production        (iii) Chicken meat        (iv) Milk production

(a) (i) and (iii)             (b) (i) and (ii)        (c) (ii) and (iii)        (d) (iii) and (iv)

Answer: (a) (i) and (iii)

[ Poultry farming is mainly done for egg production and chicken meat. Milk production is from cattle, not poultry. ]

13. Poultry fowl are susceptible to the following pathogens

(a) Viruses       (b) Bacteria        (c) Fungi          (d) All of the above

Answer:  (d) All of the above

[ Poultry birds can be infected by viruses, bacteria and fungi, which cause different diseases affecting their health and production. ]

14. Which one of the following fishes is a surface feeder?

(a) Rohus       (b) Mrigals         (c) Common carps         (d) Catlas

Answer: (d) Catlas

[ Catla fish feeds mainly on food available at the surface of water, like plankton. Hence it is known as a surface feeder in composite fish culture.]

15. Animal husbandry is the scientific management of

(i) animal breeding      (ii) culture of animals     (iii) animal livestock    (iv) rearing of animals

(a) (i), (ii) and (iii)         (b) (ii), (iii) and (iv)     (c) (i), (ii) and (iv)          (d) (i), (iii) and (iv)

Answer: (d) (i), (iii) and (iv)

[ Animal husbandry means scientific management of animal breeding, livestock and rearing of animals for useful products like milk, eggs, meat and wool. ]

16. Which one of the following nutrients is not available in fertilizers?

(a) Nitrogen       (b) Phosphorus           (c) Iron             (d) Potassium

Answer: (c) Iron
[ Fertilisers mainly supply Nitrogen (N), Phosphorus (P) and Potassium (K) to plants. Iron is a micronutrient and is generally not provided by common fertilisers. ]

17. Preventive and control measures adopted for the storage of grains include

(a) strict cleaning      (b) proper disjoining      (c) fumigation        (d) all of the above

Answer:  (d) all of the above

[ Safe grain storage requires cleaning, proper drying and fumigation to prevent damage by insects, pests and microorganisms. ]

Short Answer Questions

18. Match the column A with the column B

      (A)                                      (B)

(a) Catla                                (i) Bottom feeders

(b) Rohu                                (ii) Surface feeders

(c) Mrigal                              (iii) Middle-zone feeders

(d) Fish farming                     (iv) Culture fishery

Answer: (a) Catla → (ii) Surface feeders

(b) Rohu → (iii) Middle-zone feeders

(c) Mrigal → (i) Bottom feeders

(d) Fish farming → (iv) Culture fishery

[ Catla feeds on zooplankton at the surface, Rohu in the middle zone, Mrigal at the bottom, and fish farming is called culture fishery (culturing fish in controlled water bodies).]

19. Fill in the blanks

(a) Pigeon pea is a good source of ———.

(b) Berseem is an important———crop.

(c) The crops which are grown in rainy season are called———crops.

(d) ———are rich in vitamins.

(e) ——— crop grows in winter season.

Answer: (a) Pigeon pea is a good source of protein.
(b) Berseem is an important fodder crop.
(c) The crops which are grown in rainy season are called kharif crops.
(d) vegetables (Fruits and vegetables) are rich in vitamins.
(e) Rabi crop grows in winter season.

20. What is a GM crop ? Name any one such crop which is grown in India.

Answer: A Genetically Modified (GM) crop is a plant whose genes are changed using genetic engineering to improve qualities like pest resistance or higher yield.  Example : Bt cotton.

21. List out some useful traits in improved crop?

Answer:  Some useful traits in improved crops are:

(i) Higher yield : increased production of crop per acre.

(ii) Improved quality : better nutritional value, for example protein quality in pulses, oil quality in oilseeds.

(iii) Biotic resistance : resistance to diseases, pests and insects caused by living organisms.

(iv) Abiotic resistance : resistance to drought, salinity, heat, cold and waterlogging.

(v) Change in maturity duration : shorter maturity period reduces cost of cultivation and makes the crop available early.

(vi) Wider adaptability : ability to grow in different environmental conditions and regions.

(vii) Desirable agronomic characteristics : tallness and profuse branching in fodder crops, dwarfness in cereals so that less nutrients are consumed.

22. Why is organic matter important for crop production?

Answer: Organic matter is important for crop production because it improves soil fertility and structure. It increases the water-holding capacity of soil, supplies nutrients to plants, and supports useful microorganisms. This helps plants grow better and produce higher yield.

23. Why is excess use of fertilizers detrimental for environment?

Answer: Excess fertilisers get washed away due to over-irrigation, causing water pollution. Continuous use reduces soil fertility, as organic matter is not replenished and beneficial microorganisms are harmed by the chemicals. Although fertilisers provide short-term benefits, they can cause long-term damage, making careful application with the proper dose and timing essential.

24. Give one word for the following

(a) Farming without the use of chemicals as fertilizers, herbicides and pesticides is known as ———.

(b) Growing of wheat and groundnut on the same field is called as ———.

(c) Planting soyabean and maize in alternate rows in the same field is called as ———.

(d) Growing different crops on a piece of land in pre-planned succession is known as———.

(e) Xanthium and Parthenium are commonly known as———.

(f) Causal organism of any disease is called as ———.

Answer: (a) Farming without the use of chemicals as fertilizers, herbicides and pesticides is known as organic farming .

(b) Growing of wheat and groundnut on the same field is called as mixed cropping .

(c) Planting soyabean and maize in alternate rows in the same field is called as intercropping .

(d) Growing different crops on a piece of land in pre-planned succession is known as crop rotation .

(e) Xanthium and Parthenium are commonly known as weeds .

(f) Causal organism of any disease is called as pathogen .

25. Match the following A and B

           (A)                                                                      (B)

(a) Cattle used for tilling and carting         (i) Milk producing female

(b) Indian breed of chicken                       (ii) Broiler

(c) Sahiwal, Red Sindhi                            (iii) Drought animals

(d) Milch                                                    (iv) Local breed of cattle

(e) Chicken better fed for obtaining            (v) Aseel meat

Answer:  (a) Cattle used for tilling and carting → (iii) Draught animals

(b) Indian breed of chicken → (v) Aseel

(c) Sahiwal, Red Sindhi → (iv) Local breed of cattle

(d) Milch → (i) Milk producing female

(e) Chicken better fed for obtaining → (ii) Broiler

26. If there is low rainfall in a village throughout the year, what measures will you suggest to the farmers for better cropping?

Answer: If a village has low rainfall, farmers should grow drought-resistant crops like millets and pulses, use rainwater harvesting techniques, apply mulching to retain soil moisture, adopt drip irrigation for efficient water use, and practise crop rotation to maintain soil fertility. These measures ensure better yields with less water.

27. Group the following and tabulate them as energy yielding, protein yielding, oil yielding and fodder crop.

Wheat, rice, berseem, maize, gram, oat, pigeon gram, sudan grass, lentil, soyabean, groundnut, castor and mustard.

Answer: The group of Crops is :

Energy Yielding Crops	Protein Yielding Crops	Oil Yielding Crops	Fodder Crops
wheat , rice , maize	gram,  pigeon gram and lentil	soyabean, groundnut, castor and mustard	berseem, oat and sudan grass

28. Define the term hybridization and photoperiod.

Answer: Hybridization is the process of crossing two genetically different plants to produce a new variety with desirable traits like higher yield, disease resistance, or better quality.
Photoperiod is the duration of light received by plants in a day, which affects their growth and flowering.

29. Fill in the blanks

(a) Photoperiod affect the————.

(b) Kharif crops are cultivated from————to————.

(c) Rabi crops are cultivated from————to————.

(d) Paddy, maize, green gram and black gram are————crops.

(e) Wheat, gram, pea, mustard are————crops.

Answer: (a) Photoperiod affects the flowering (of plants).
(b) Kharif crops are cultivated from June to October.
(c) Rabi crops are cultivated from November to April.
(d) Paddy, maize, green gram and black gram are kharif crops.
(e) Wheat, gram, pea, mustard are rabi crops.                                                             

30. Cultivation practices and crop yield are related to environmental condition. Explain.

Answer: Cultivation practices and crop yield depend on weather, soil quality and water availability. Unpredictable conditions like drought or floods affect growth, so crops that can tolerate diverse climates or high soil salinity are preferred for better yield.

31. Fill in the blanks

(a) A total of———nutrients are essential to plants.

(b) ———and———are supplied by air to plants.

(c) ———is supplied by water to plants.

(d) Soil supply———nutrients to plants.

(e) ———nutrients are required in large quantity and called as———.

(f) ——— nutrients are needed in small quantity for plants and are called ———.

Answer: (a) A total of 16 nutrients are essential to plants.

(b) Carbon and oxygen are supplied by air to plants.

(c) Hydrogen is supplied by water to plants.

(d) Soil supply 13 nutrients to plants.

(e) Six nutrients are required in large quantity and called as macronutrients.

(f) Seven nutrients are needed in small quantity for plants and are called micronutrients.

32. Differentiate between compost and vermicompost?

Answer: The difference between compost and vermicompost are :

Compost	Vermicompost
(i) Prepared by decomposing farm waste like cow dung, vegetable waste, straw, and weeds in pits.	(i) Prepared by using earthworms to decompose plant and animal waste.
(ii) Rich in organic matter and nutrients.	(ii) Rich in organic matter, nutrients and beneficial microbes.
(iii) Decomposition is natural and slower.	(iii) Decomposition is faster due to earthworm activity.
(iv) Does not involve living organisms in the process.	(iv) Earthworms play a key role in the process.

33. Arrange these statements in correct sequence of preparation of green manure.

(a) Green plants are decomposed in soil.

(b) Green plants are cultivated for preparing manure or crop plant parts are used.

(c) Plants are ploughed and mixed into the soil.

(d) After decomposition it becomes green manure.

Answer:  (b) → (c) → (a) → (d)

(b) Green plants are cultivated for preparing manure or crop plant parts are used.

(c) Plants are ploughed and mixed into the soil.

(a) Green plants are decomposed in soil.

(d) After decomposition it becomes green manure.

34. An Italian bee variety A. mellifera has been introduced in India for honey production. Write about its merits over other varieties.

Answer: Merits of Italian bee (A. mellifera) over other varieties are:

(i) High honey collection capacity, giving more yield.

(ii) Sting less, making them safer to handle.

(iii) Stay longer in a given beehive, ensuring stability.

(iv) Breed well, supporting larger colonies for commercial honey production.

35. In agricultural practices, higher input gives higher yield. Discuss how?

Answer: In agriculture, higher input like quality seeds, fertilisers, irrigation and pest control improves plant growth and health. Proper management of these resources increases crop productivity, reduces losses, and ensures better yield. However, inputs must be balanced and sustainable to avoid soil damage or environmental harm. 

Long Answer Questions

36. Discuss the role of hybridisation in crop improvement.

Answer: Hybridisation plays an important role in crop improvement by combining desirable traits of two different varieties of crops. It helps to produce crops with higher yield, better quality, disease resistance, pest resistance and improved adaptability to different environmental conditions. Thus, hybridisation increases agricultural productivity.

37. Define (i) Vermicompost     (ii) Green manure      (iii) Bio fertilizer

Answer:  (i) Vermicompost is organic manure prepared with the help of earthworms, which decompose plant and animal waste into nutrient-rich compost.

(ii) Green manure is the decomposed green plants or crop residues mixed into the soil to improve fertility and organic content.

(iii) Biofertilizers are microorganisms that enrich the soil by increasing the availability of nutrients like nitrogen and phosphorus to plants.

38. Discuss various methods for weed control.

Answer: Methods for Weed Control:

(i) Chemical method: Use herbicides to kill weeds, but overuse can harm crops, animals and the environment.

(ii) Mechanical method: Remove weeds manually or by ploughing to clear fields physically.

(iii) Preventive methods: Include timely sowing, proper seed bed preparation, intercropping, crop rotation, resistant varieties and summer ploughing to reduce weed growth naturally.

39. Differentiate between the following

(i) Capture fishery and Culture fishery      (ii) Mixed cropping and Inter cropping      (iii) Bee keeping and Poultry farming

Answer: (i) The difference between the Capture fishery and Culture fishery :

Capture Fishery	Culture Fishery
(i) Fish are caught from natural water bodies like rivers, lakes, and oceans.	(i) Fish are reared in artificial ponds or tanks under controlled conditions.
(ii) Yield depends on the natural availability of fish.	(ii) Yield is controlled and higher due to proper management.
(iii) Less human intervention in breeding and growth.	(iii)Requires management of breeding, feeding, and water quality.

(ii) The difference between the mixed cropping and intercropping are :

Mixed Cropping	Intercropping
(i) Two or more crops are grown together randomly on the same field.	(i) Two or more crops are grown in a planned pattern, usually in alternate rows.
(ii) Mainly reduces the risk of total crop failure.	(ii) Improves land use efficiency and helps control pests and weeds.
(iii) Crops do not follow a specific arrangement.	(iii) Crops are carefully arranged for better growth and yield.

(iii) The difference between the bee keeping and poultry farming are :

Bee Keeping (Apiculture)	Poultry Farming
(i) Rearing bees to obtain honey, wax, and other products.	(i) Rearing chickens, ducks, or turkeys for meat and eggs.
(ii) Requires beehives and flowering plants for bees to thrive.	(ii) Requires coops, feed, and water management for birds.
(iii) Bees are insects, less space needed per colony.	(iii) Birds are larger animals, need more space and care.
(iv) Focus on honey production and pollination.	(iv) Focus on food production (meat and eggs) for human consumption.

40. Give the merits and demerits of fish culture?

Answer:  Merits of fish culture:

(i) Provides a regular supply of high-quality protein food.

(ii) Generates income and employment opportunities.

(iii) Allows rearing of desired fish species in controlled conditions.

Demerits of fish culture:

(i) Risk of disease spread due to high population density.

(ii) Requires regular maintenance, feeding and investment.

(iii) Water quality management is difficult and costly.

41. What do you understand by composite fish culture?

Answer: Composite fish culture is a method of rearing multiple species of fish with different food habits together in the same pond. This ensures that all available food resources in the pond are utilized efficiently, leading to increased fish production. For example, Catla, Rohu and Mrigal are grown together.

42. Why bee keeping should be done in good pasturage?

Answer: Bee keeping should be done in good pasturage because it provides bees with abundant nectar and pollen. This ensures better honey production, proper nutrition for bees and stronger colonies. Good pasturage also helps in cross-pollination of nearby crops.

43. Write the modes by which insects affect the crop yield.

Answer: Insects affect crop yield in three ways:

(i) by cutting roots, stems and leaves,

(ii) by sucking cell sap from different parts of the plant, and

(iii) by boring into stems and fruits.

44. Discuss why pesticides are used in very accurate concentration and in very appropriate manner?

Answer: Pesticides are used in accurate concentrations and in an appropriate manner because:
(i) Higher concentrations can kill useful organisms like pollinators (bees) and soil microbes, and may also cause health hazards to humans and animals.
(ii) Lower concentrations may not kill pests, allowing them to develop resistance.
(iii) Proper usage prevents environmental pollution and biomagnification in food chains.

45. Name two types of animal feed and write their functions.

Answer:  Two types of animal feed are:
(i) Roughage: It provides fibre and bulk and helps in digestion and proper bowel movement.
(ii) Concentrates: They provide proteins, carbohydrates and fats for growth, milk production, and energy.

46. What would happen if poultry birds are larger in size and have no summer adaptation capacity? In order to get small sized poultry birds, having summer adaptability, what method will be employed?

Answer: If poultry birds are larger in size and have no summer adaptation capacity, they may suffer from heat stress, need more food and show low egg and meat production in summer. To obtain small-sized poultry birds with summer adaptability, cross-breeding between local and improved breeds will be employed.

47. Suggest some preventive measures for the diseases of poultry birds.

Answer: Preventive measures for diseases of poultry birds are:

(i) Maintain proper cleanliness in poultry houses to prevent the spread of germs.

(ii) Provide balanced and nutritious feed to keep birds healthy.

(iii) Give clean and fresh drinking water regularly.

(iv) Vaccinate the birds against common poultry diseases.

(v) Isolate sick birds from healthy ones to stop infection from spreading.

(vi) Ensure proper ventilation and space in the poultry farm.

48. Figure15.1 shows the two crop fields [Plots A and B] have been treated by manures and chemical fertilizers respectively, keeping other environmental factors same. Observe the graph and answer the following questions.

(i) Why does plot B show sudden increase and then gradual decrease in yield?

(ii) Why is the highest peak in plot A graph slightly delayed?

(ii) What is the reason for the different pattern of the two graphs?

  

                      Fig. 15.1

Answer: (i) Plot B (chemical fertilizers) shows a sudden yield increase because chemical fertilizers supply quick nutrients, but long-term overuse reduces soil fertility and yield.

(ii) The peak in Plot A (manure) is delayed because manure contains organic matter that soil microbes must decompose before nutrients are released.

(iii) Different patterns arise because chemical fertilisers give a quick, short-term nutrient supply, while manures release nutrients slowly and improve long-term soil fertility and structure.

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