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Improvement In Food Resources

Class 9th Science NCERT Exemplar Solution
Multiple Choice Questions
  1. Which one is an oil yielding plant among the following?A. Lentil B. Sunflower C.…
  2. Which one is not a source of carbohydrate?A. Rice B. Millets C. Sorghum D. Gram…
  3. Find out the wrong statement from the followingA. White revolution is meant for increase…
  4. To solve the food problem of the country, which among the following is necessary?A.…
  5. Find out the correct sentence (i) Hybridisation means crossing between genetically…
  6. Weeds affect the crop plants byA. killing of plants in field before they grow B.…
  7. Which one of the following species of honey bee is an Italian species?A. Apis dorsata B.…
  8. Find out the correct sentence about manure (i) Manure contains large quantities of organic…
  9. Cattle husbandry is done for the following purposes (i) Milk Production (ii) Agricultural…
  10. Which of the following are Indian cattle? (i) Bos indicus (ii) Bos domestica (iii) Bos…
  11. Which of the following are exotic breeds? (i) Brawn (ii) Jersey (iii) Brown Swiss (iv)…
  12. Poultry farming is undertaken to raise following (i) Egg production (ii) Feather…
  13. Poultry fowl are susceptible to the following pathogensA. Viruses B. Bacteria C. Fungi D.…
  14. Which one of the following fishes is a surface feeder?A. Rohus B. Mrigala C. Common carps…
  15. Animal husbandry is the scientific management of (i) animal breeding (ii) culture of…
  16. Which one of the following nutrients is not available in fertilizers?A. Nitrogen B.…
  17. Preventive and control measures adopted for the storage of grains includeA. strict…
Short Answer Type
  1. Match the column A with the column B (A) (B) (a) Catla (i) Bottom feeders (b) Rohu (ii)…
  2. (a) Pigeon pea is a good source of _______ (b) Berseem is an important ________ crop. (c)…
  3. What is a GM crop? Name any one such crop which is grown in India.…
  4. List out some useful traits in improved crop?
  5. Why is organic matter important for crop production?
  6. Why is excess use of fertilizers detrimental for environment?
  7. Give one word for the following (a) Farming without the use of chemicals as fertilizers,…
  8. Match the following A and B (A) (B) (a) Cattle used for tilling and carting (i) Milk…
  9. If there is low rainfall in a village throughout the year, what measures will you suggest…
  10. Group the following and tabulate them as energy yielding, protein yielding, oil yielding…
  11. Define the term hybridization and photoperiod.
  12. (a) Photoperiod affect the_____ (b) Kharif crops are cultivated from _____to______. (c)…
  13. Cultivation practices and crop yield are related to environmental condition. Explain.…
  14. Fill in the blanks: (a) A total of _____nutrients are essential to plants. (b) _____and…
  15. Differentiate between compost and vermicompost?
  16. Arrange these statements in correct sequence of preparation of green manure. (a) Green…
  17. An Italian bee variety A. mellifera has been introduced in India for honey production.…
  18. In agricultural practices, higher input gives higher yield. Discuss how?…
Long Answer Type
  1. Discuss the role of hybridisation in crop improvement.
  2. Define (i) Vermi compost (ii) Bio fertilizer (iii) Green manure
  3. Discuss various methods for weed control.
  4. Differentiate between the following (i) Capture fishery and Culture fishery (ii) Mixed…
  5. Give the merits and demerits of fish culture?
  6. What do you understand by composite fish culture?
  7. Why beekeeping should be done in good pasturage?
  8. Write the modes by which insects affect the crop yield.
  9. Discuss why pesticides are used in very accurate concentration and in very appropriate…
  10. Name two types of animal feed and write their functions.
  11. What would happen if poultry birds are larger in size and have no summer adaptation…
  12. Suggest some preventive measures for the diseases of poultry birds.…
  13. Figure 15.1 shows the two crop fields [Plots A and B] have been treated by manures and…
  14. Complete the crossword puzzle (Fig.15.2) Across 1. Oil yielding plant (9) 3. Crop grown in…

Multiple Choice Questions
Question 1.

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

B. Sunflower

C. Cauliflower

D. Hibiscus


Answer:

Sunflower oil is the non-volatile oil compressed from the seeds of sunflower (Helianthus annuus). Sunflower oil is commonly used in food as a frying oil, and in cosmetic formulations as an emollient.


Question 2.

Which one is not a source of carbohydrate?
A. Rice

B. Millets

C. Sorghum

D. Gram


Answer:

black gram, black lentil, It is one of the important pulse crop grown throughout India.


Generally it is consumed in the form of ‘Dal’. It contains protein (25%), carbohydrates (60%), fat (1.3%) and rich in phosphoric acid. It accounts 13 % total pulses area and 10 % total pulses production in India.


Question 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:

White revolution, blue revolution and sustainable agricultural activities have led to improvement in agricultural products.


Question 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:

All of the above


Question 5.

Find out the correct sentence

(i) Hybridisation means crossing between genetically dissimilar plants

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

(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 hybridization.
A. (i) and (iii)

B. (ii) and (iv)

C. (ii) and (iii)

D. (iii) and (iv)


Answer:

Hybridization and GMO Crops genetically modified crops have led to increase in the crop production by combining the best combinations desired in the crops.


Question 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:

Weeds take up space light and nutrients meant for the main crop. They deprive the main crop of essential nutrients and reduce its yield.


Question 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:

Honey bee is eusocial, creating colonies with a single fertile female (or "queen"), many sterile females or "workers", and small proportion of fertile males or "drones". It is one of the first domesticated insects, and is the primary species maintained by beekeepers to this day for both its honey and pollination services.


Question 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:

Manure is organic matter, mostly derived from animal feces except in the case of green manure, which can be used as organic fertilizer in agriculture. Manures contribute to the fertility of the soil by adding organic matter and nutrients, such as nitrogen, that are trapped by bacteria in the soil.


Question 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:

Cattle husbandry helps us in developing high yielding breeds of various domestic animals through cross breeding. Thus, animal husbandry increases the availability of various food products such as milk, eggs and meat, which are obtained from domestic animals.


Question 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:

Indian cattle (Bos indicus) and riverine buffalo (Bubalus bubalis) give a poor yield of milk but it has a high fat and protein percentage compared to taurine cattle.


Question 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:

Jersey cattle are a small breed of dairy cattle. It is popular for the high butterfat content of its milk and the lower maintenance costs attending its lower body weight.


Brown Swiss is a North American breed of dairy cattle. It derives from the Alpine Braunvieh. After the Holstein Friesian, it has the second-highest annual milk yield, over 9,000 kg. The Brown Swiss originated on the slopes of the Alps in Switzerland; because they were bred in this harsh climate, they are resistant to the heat, cold and many other common cattle problems.


Question 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:

Poultry farming. Poultry farming is the process of raising domesticated birds such as chickens, ducks, turkeys and geese for the purpose of farming meat or eggs for food. More than 50 billion chickens are raised annually as a source of food, for both their meat and their eggs.


Question 13.

Poultry fowl are susceptible to the following pathogens
A. Viruses

B. Bacteria

C. Fungi

D. All of the above


Answer:

An infectious disease is any disease caused by invasion of a host by a pathogen which subsequently grows and multiplies in the body. Infectious diseases are often contagious, which means they can be spread directly or indirectly from one living thing to another. These include Avian Encephalomyelitis, Avian Influenza, Avian Tuberculosis, Chicken Anaemia Virus Infection (or CAV), Chlamydiosis, Egg Drop Syndrome (or EDS), Fowl Cholera (or Pasteurellosis), Fowl Pox, Infectious Bronchitis.


Question 14.

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

B. Mrigala

C. Common carps

D. Catlas


Answer:

Fish that are known as surface feeders all have a back that is perfectly straight, this allows for their upturned mouths to easily get right on the surface and scoop up the food, in their natural habitat they would do this to eat insects on the water surface.


Question 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:

Animal husbandry is the management and care of farm animals by human beings, in which genetic qualities and behavior, considered to be advantageous to humans, are further developed.


Question 16.

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

B. Phosphorus

C. Iron

D. Potassium


Answer:

NPK fertilizers are three-component fertilizers providing nitrogen, phosphorus, and potassium. Iron for plants can come from a number of sources. Ferric oxide is a chemical present in soil that gives dirt a distinctive red color, and plants can absorb iron from this chemical.


Question 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:

Proper storage of grains leads to maintenance of productivity. Grains also if stored properly can be saved from insects, pathogens and decomposition.



Short Answer Type
Question 1.

Match the column A with the column B


Answer:



The above matched column show the name of different species of fish and their characteristics as per their feeding zones.



Question 2.

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) Protein


The pigeon pea plant is extensively cultivated in different parts of India. Pigeon Peas are high in nutritional elements. Following is a list of nutritional content in per 168 g or 1 cup of pigeon peas.


(b) Fodder


Berseem is one of the most important fodder crops and has been rightly described as the king of fodders. It is highly esteemed fodder which has a special place in animal husbandry programmes throughout the country does not tolerate acidic soils but grows in other kinds of soils except user lands. The crop is sown from middle of September to end of October in plains and from middle of August to first week of September in hills. Berseem is highly palatable fodder and it contains 17% crude protein and 25.9% crude fibre. The total digestible nutrients content is 60-65%.


(c) Kharif


Kharif crops grow during the rainy seasons. They are sown at the start of the monsoon and harvested at the end of the monsoon season. Example is Paddy, Maize and Millet etc.


(d) Vegetables


Vegetables can be eaten either raw or cooked and play an important role in human nutrition, being mostly low in fat and carbohydrates, but high in vitamins, minerals and dietary fiber. Many nutritionists encourage people to consume plenty of fruit and vegetables.


(e) Rabi


The major rabi crop in India is wheat, followed by barley, mustard, sesame and peas. Rabi crops (Winter crops): Crops which are grown during the winter season(October-March) are called Rabi crops.



Question 3.

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


Answer:

Crop which has been developed by introducing a new gene from any other source, to obtain the desired character, is called as genetically modified (GM) crop. Bt Cotton is an example of GM crop which is made insect- resistant by introducing a new gene from a bacteria.



Question 4.

List out some useful traits in improved crop?


Answer:

The useful traits of improved crops are

(a) higher yield


(b) improved nutritional quality


(c) resistance to biotic and abiotic stresses


(d) change in maturity


(e) wide range of adaptability


(f) desired agronomic characteristics.



Question 5.

Why is organic matter important for crop production?


Answer:

The Organic matter is important for crops because

(a) it helps in improving soil structure.


(b) it helps in increasing water holding capacity of sandy soil.


(c) in clayey soil large quantity of organic matter helps in drainage and in avoiding water logging.



Question 6.

Why is excess use of fertilizers detrimental for environment?


Answer:

The excess use of fertilizers causes environmental pollution as their residual and unused amounts will become pollutants for air, water and soil.



Question 7.

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 soybean 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) Organic Farming.


Organic farming is an alternative agricultural system which originated early in the 20th century in reaction to rapidly changing farming practices. Organic agriculture continues to be developed by various organic agriculture organizations today. It relies on fertilizers of organic origin such as compost, manure, green manure, and bone meal and places emphasis on techniques such as crop rotation and companion planting. Biological pest control, mixed cropping and the fostering of insect predators are encouraged.


(b) Mixed cropping.


Mixed farming exists in many forms depending on external and internal factors. External factors are weather patterns, market prices, political stability, technological developments, etc. Internal factors relate to local soil characteristics, composition of the family and farmers' ingenuity. Farmers can decide to opt for mixed enterprises when they want to save resources by interchanging them on the farm - because these permit wider crop rotations and thus reduce dependence on chemicals, because they consider mixed systems closer to nature, or because they allow diversification for better risk management.


(c) Intercropping


Intercropping is a multiple cropping practice involving growing two or more crops in proximity. The most common goal of intercropping is to produce a greater yield on a given piece of land by making use of resources or ecological processes that would otherwise not be utilized by a single crop.


(d) Crop rotation.


The growing of different crops in succession on a piece of land to avoid exhausting the soil and to control weeds, pests, and diseases.


(e) Weeds


Weeds are plants that grow near the main crop and take up the nutrients, soil and water of the main crop. They also deprive main plant of nutrition.


(f) Pathogen.


An agent that causes infection or disease, especially a microorganism, such as a bacterium or protozoan, or a virus. Examples Nematodes, Protozoa and Algae.



Question 8.

Match the following A and B


Answer:



The above listed names in the column are the animals that are categorized into milk and meat producing animals. These animals are also used in farms as draught animals.



Question 9.

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


Answer:

Farmers of low rainfall area will be suggested to

(a) practice farming with drought resistant and early maturing varieties of crops.


(b) to enrich the soil with more humus content as it increases the water- holding capacity and retains water for longer duration.



Question 10.

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 correct answer is

(1) Energy yielding— wheat, rice, maize


(2) Protein yielding— gram, pigeon gram, lentil, soybean


(3) Oil yielding— groundnut, castor, mustard, soybean


(4) Fodder crops— berseem, oat, sudan grass


Different plants are categorized as per the kind of product they yield. If a plant yield energy after consumption then it is known as energy yielding plant.



Question 11.

Define the term hybridization and photoperiod.


Answer:

Hybridisation— Hybridisation refers to crossing between genetically dissimilar organisms.

Photoperiod— Duration of sunlight available to the plant is called as photoperiod. It affects the growth, flowering and maturation of crops.



Question 12.

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) Flowering of plant


Photoperiodism is the physiological reaction of organisms to the length of day or night. It occurs in plants and animals. Photoperiodism can also be defined as the developmental responses of plants to the relative lengths of light and dark periods.


(b) June to October.


The kharif crops include rice, maize, sorghum, pearl millet/bajra, finger millet/ragi (cereals), arhar (pulses), soyabean, groundnut (oilseeds), cotton etc.


(c) November to April


The rabi crops include wheat, barley, oats (cereals), chickpea/gram (pulses), linseed, mustard (oilseeds) etc.


(d) Kharif


(e) Rabi



Question 13.

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


Answer:

The different crops and cultivation practices require different climatic conditions, temperature, photoperiod for their growth and completion of life cycle. There are some crops which are grown in rainy season (Kharif crops) while some others are grown during winter season (Rabi crops).



Question 14.

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) 16.


Nitrogen (N), Phosphorus (P), and Potassium (K), Calcium (Ca), Magnesium (Mg), and Sulfur (S), Boron (B), Chlorine (CI), Copper (Cu), Iron (Fe), Manganese (Mn), Molybdenum (Mo), and Zinc (Zn).


(b) Carbon and Oxygen


In photosynthesis, sunlight, water, and carbon dioxide are combined in special cells inside the plant. Glucose is one product of photosynthesis. Glucose is a sugar that plants can use for energy. Plants release oxygen as a waste product.


(c) Hydrogen


Hydrogen also is necessary for building sugars and building the plant. It is obtained almost entirely from water.


(c) 13


Soil is an important factor that provides essential nutrients to soil.


(d) Six, Macronutrients


The major macronutrients are nitrogen (N), phosphorous (P), and potassium (K). Calcium (Ca), magnesium (Mg), and sulfur (S) are also macronutrients.


(e) Seven, Micronutrients


Boron (B), Zinc (Zn), Manganese (Mn), Iron (Fe), Copper (Cu), Molybdenum (Mo), Chlorine (Cl).



Question 15.

Differentiate between compost and vermicompost?


Answer:

Compost — Compost formation is the process in which farm waste materials like livestock excreta, vegetable wastes, animal refuse, domestic waste, straw, eradicated weeds are decomposed and used as manure.


Vermicompost — The compost prepared from organic matter by using earthworm which hastens the process of decomposition.



Question 16.

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:

The correct answer and sequence is

(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.



Question 17.

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 variety A. mellifera are as follows


(a) It stings less.


(b) It has high honey collection capacity.


(c) It stays in given bee-hive for long periods and breeds very well.



Question 18.

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


Answer:

In agricultural practices, higher input gives higher yield. This means higher money input to raise the yield. Financial conditions of the farmers allows them to take up different farming practices and technologies. The farmer’s purchasing capacity for input decides cropping system and production practices.




Long Answer Type
Question 1.

Discuss the role of hybridisation in crop improvement.


Answer:

Hybridisation refers to crossing between genetically dissimilar plants. It may be inter varietal, interspecific and intergeneric. Two crops of good characters (desired character) are selected and crossed to obtain a new crop having desired characters of parental crops. This method of hybridisation improves crops with respect to yield, disease resistance, pest resistance etc.



Question 2.

Define

(i) Vermi compost

(ii) Bio fertilizer

(iii) Green manure


Answer:

(i) Vermicompost — Compost is a kind of manure which is rich in organic matter and nutrients. The compost prepared by using earthworms to haste the process of decomposition of plants and animals refuse is called as Vermicompost.


(ii) Bio fertilizer — Living organisms which are used as fertilizer to supply the nutrients to plants, are called as biofertilizers. For example, blue green algae, which fix nitrogen in soil, rice fields, are called as biofertilizer.


(iii) Green manure — The manure which is prepared by decomposing green plants in field itself is called green manure. For example — sunn hemp is grown in fields, mulched by ploughing and allowed to decompose in field for the preparation of green manure.



Question 3.

Discuss various methods for weed control.


Answer:

The various modes of weed control are

(a) mechanical removal


(b) proper seedbed preparation to avoid the weed growth


(c) timely sowing of crop to avoid the growth of weed.


(d) intercropping and crop rotation also help in weed control.



Question 4.

Differentiate between the following

(i) Capture fishery and Culture fishery

(ii) Mixed cropping and Intercropping

(iii) Beekeeping and Poultry farming


Answer:

(i) The Capture fishery is the method of obtaining fish from natural resources like river and sea.

Culture fishery is the method of obtaining fish by fish farming like ponds, lakes etc.


(ii) The mixed cropping is growing two or more crops simultaneously on the same piece of land; while intercropping is growing two or more crops simultaneously on the same field in a definite pattern. i.e., in different rows.


(iii) The beekeeping is the practice to rear the honey bee for obtaining honey on commercial basis.


Poultry farming is the practice to raise the domestic fowl for egg and meat production.



Question 5.

Give the merits and demerits of fish culture?


Answer:

The demerits of fish culture are

(i) threat to biodiversity


(ii) only economically important and valued fishes will be cultured.


The merits of fish culture are


(i) large amount of desired fishes can be obtained in small area


(ii) improvement can be done.



Question 6.

What do you understand by composite fish culture?


Answer:

Composite fish culture is the method to culture five or six species, both indigenous and exotic, together in a single fish pond. These species are selected so that they do not compete for food among themselves having different types of food habits. As a result food available in all the parts of the pond is used. For example— Catlas are surface feeders, Rohu is middle zone feeder and Madrigals and common carps are bottom feeders.



Question 7.

Why beekeeping should be done in good pasturage?


Answer:

beekeeping should be done in good pasturage because good pasturage provides more quantity and quality of nectar for honey to honey bees. Honey bees can get amples of vegetation to search for juices.



Question 8.

Write the modes by which insects affect the crop yield.


Answer:

The modes by which insects affect the crop yield are cutting plant parts, sucking cell sap and borers.



Question 9.

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


Answer:

Pesticides are used in very accurate concentration and in a very appropriate manner, because if used in excess it

(a) harms the soil and causes loss of fertility


(b) checks the replenishment of organic matter


(c) kills the micro organism of soil


(d) causes air, water and soil pollution.



Question 10.

Name two types of animal feed and write their functions.


Answer:

(i) Roughage is largely fibre. (ii) Concentrates are rich in proteins and nutrients.



Question 11.

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:

Maintenance of temperature is needed for better egg production by poultry birds. Therefore, larger size (increase in surface area of body) and no adaptability of summer may cause decline in egg production. To obtain the smaller size and higher summer adaptability, cross breeding of poultry birds are done. Small size is also needed for better housing and low feed.



Question 12.

Suggest some preventive measures for the diseases of poultry birds.


Answer:

Some preventive measures of poultry bird diseases are

(a) cleaning of poultry farms


(b) proper sanitation of poultry farms


(c) spraying of disinfectants at regular intervals


(d) appropriate vaccination of birds.



Question 13.

Figure 15.1 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?

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



Answer:

i) With addition of chemical fertilizer there is sudden increase in yield due to release of nutrients N,P,K etc in high quantity. The gradual decline in the graph may be due to continuous use and high quantity of chemicals which kill microbes useful for replenishing the organic matter in the soil. This decreases the soil fertility.


(ii) Manures supply small quantities of nutrients to the soil slowly as it contains large amounts of organic matter [Hint: importance of organic matter can be included]. It enriches soil with nutrients thereby increasing soil fertility continuously.


(iii) The difference in the two graphs indicate that use of manure is beneficial for long duration in cropping as the yield tends to remain high when the quantity of manure increases.


In case of Plot B the chemical fertilizers may cause various problems when used continuously for long time. Loss of microbial activity reduces decomposition of organic matter and as a result soil fertility is lost that affects the yield in long run.



Question 14.

Complete the crossword puzzle (Fig.15.2)



Across

1. Oil yielding plant (9)

3. Crop grown in winter season (4)

5. Fixed by Rhizobium (8)

9. Common honey bee (4)

Downward

2. Animal feed (6)

4. A micronutrient (5)

6. Unwanted plant in crop fields (4)

7. An exotic breed of chicken(7)

8. Bottom feeders in fish pond(7)

10. A marine fish (4)


Answer: