NCERT Exemplar Problems Class 9 Science Chapter 15 Improvement in Food Resources

In this chapter, we provide NCERT Exemplar Problems Solutions for Class 9 Science Chapter 15 Improvement in Food Resources for English medium students, Which will very helpful for every student in their exams. Students can download the latest NCERT Exemplar Problems Solutions for Class 9 Science Chapter 15 Improvement in Food Resources pdf, free NCERT Exemplar Problems Solutions for Class 9 Science Chapter 15 Improvement in Food Resources book pdf download. Now you will get step by step solution to each question.

TextbookNCERT
ClassClass 9
SubjectScience
ChapterChapter 15
Chapter NameImprovement in Food Resources
CategoryNCERT Exemplar

NCERT Exemplar Problems Class 9 Science Chapter 15 Improvement in Food Resources

Multiple Choice Questions (MCQs)

Question 1:
Which one is an oil yielding plant among the following?
(a) Lentil              (b) Sunflower                 (c) Cauliflower                   (d) Hibiscus
Answer:
(b)
Oil seed crops include cotton seed, niger (Ramtil), sunflower, soyabean, linseed oil, rapeseed, groundnut, sesame, mustard, sunflower, olive, etc. These are sources of oil, fats and tatty acids and are typically high in unsaturated fats, when these seeds are consumed in moderation these are regarded as healthy foods. Coconut oil and palm oil are cheap sources of cooking medium.
Castor oil is not edible oil. It is mainly used as a lubricant or purgative, in the manufacturing of transparent soaps, inks, paints, phenyls, hair fixers, etc.
Lentil is used as pulses, cauliflower is an inflorescence which is used as vegetable and Hibiscus is an ornamental flowering plant.

You can also Download NCERT Exemplar Class 9 Science Solutions to help you to revise complete Syllabus and score more marks in your examinations.

Question 2:
Which one is not a source of carbohydrate?
(a) Taj Rice                    (b) Millets                  (c) Sorghum             (d) Gram
Answer:
(d)
Cereals like wheat, rice, maize, barley, sorghum, etc., are rich source of carbohydrates.
Pulses include legumes such as chick pea, gram (chana), pea (matar), black gram
(urad), green gram (moong), pigeon pea (arhar), cow pea (lobia) and lentil (masoor)
are rich sources of proteins.

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:
(d)
Operation Flood is a project of the National Dairy Development Board (NDDB) which was the world’s biggest dairy development program which made India, a milk-sufficient nation, the largest milk producer in the world. The father of the white revolution in India was Verghese Kurien. The white mentioned is used for milk production.
He was able to implement programs that took India from a country with very little dairy production to the world’s largest producer.
The blue revolution is similar to the green revolution only that it deals with aquaculture and water preservation for human use . In India the blue revolution has been used for several years for fish production, In 1930’s, India produced 600,000 tonnes of fish and due to blue revolution, India produced 1.6 million tonnes of fish. It has assisted India to produce more fresh water fish.
Sustainable agriculture can be defined as adoption of various farming and production management technique to maximise agricultural need.

Question 4:
To solve the food problem of the country, which among the following is necessary?
(i)   Increased production and storage of food grains
(ii)  Easy access of people to the food grain
(iii) People should have money to purchase the grains
(iv) All of the above
Answer:
(d)
With 1.04 billion people, our country ranks second in population growth around the world. According to an estimate, by the year 2020, Indian population would rise to about 1.343 billion. It is estimated that to feed such a huge population, we will require at least 241 million tonnes of grain production per annum. Therefore, it is necessary to increase production of both, plants and animals.
Even in the past, to meet the demands of growing Indian population, our scientists (such as Swaminathan, Kurein) adopted methods to increase food production. A variety of ‘revolutions’, helped India in becoming self-reliant.
These revolutions include green revolution (high production of food grains), blue ‘revolution (enhanced fish production), white revolution (increased milk production)
and yellow revolution (increased oil production). Our scientists are continuously making efforts to increase the pulse production, i.e., golden revolution.

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 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)
The crossing between genetically unidentical plants to produce a new variety, i.e., hybrid is called hybridisation. Crossing may be between two different varieties (intra varietal cross breeding), between two different species of some genus (interspecific cross breeding) and between different genera (intergeneric cross breeding).
Genetically, modified crops can be produced by insertion of genes with desired traits by the process of hybridisation.

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 :
(d) Weeds are unwanted plants in the cultivated fields. They compete with main crop plants for nutrients and reduce the growth of crops in many ways. The seeds of weed germinate easily, their seedlings grow faster, they flower early, their seed production begins after a very short growth period and produce many seeds.

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:
(d) Both indigenous and exotic varieties of honey bees are used for commercial production of honey in India.
A.Indigenous varieties
Apis cerona indica F. (Indian honey bee)
Apis dorsata F. (Rock bee)
Apis florae F. (Little bee)
B.Exotic varieties
Apis mellifera (European or Italian bee)
Apis adomsoni (South African bee)

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:
(b) Manures are the natural fertilisers. They are bulky sources of organic matter which supply nutrients in small quantities, and organic matter in large quantities. Manures are prepared by the decomposition of animal excreta and plant waste. Manures include Farm Yard Manure (FYM), compost, green manures, vermicompost etc.
Advantages of manures Manures affect the soil in following three ways
(i)   Manures enrich the soil with nutrients and replenish the general deficiency of nutrients in the soil.
(ii)  Manures add organic matter (called humus) to the soil which restores the soil texture, for better retention of water and aeration of soil.
(iii) The organic matter in manures provides food for the soil organisms, (decomposers such as bacteria, fungi, etc), which help in providing nutrients to plants.

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:
(a) The branch of agriculture that deals with feeding, caring and breeding of domestic animals is called animal husbandry (use carefully without waste). In India, cattle are next to land in use for farmers. Human beings domesticate cattle for milk production, agricultural work, Meat production, transportation and leather, etc.

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:
(a) Bos indicus or zebu or humped cattle is Indian breed.
Bos domestica is currently found in Africa, Asia, Eastern and Western Europe, Parts of North America and South America.
Bos bubalis wild water buffalo or Bos bubalis occur in India, Nepal, Bhutan, Thailand and Cambodia.

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:
(b) Exotic breeds are those breeds that are not native to that place. Brown Swiss and Jersey Swiss are the exotic breeds of cow. Some other exotic breed of cow are Vechur cow (smallest breed in the world), Swiss brown, Holstein Friesian, Jersey cow and Ayershire (Scotland).

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:
(a)
The poultry industry with its production in the form of eggs and meat is of particular importance in providing a balanced diet for human population. They are not only efficient converters of agricultural by products but also provide egg, feathers and rich manure.

Question 13:
Poultry fowl are susceptible to the following pathogens
(a) viruses               (b) bacteria                (c) fungi                    (d) All of these
Answer:
(d) Common diseases caused by different pathogen of fowl are

15-14
15-14

Question 14:
Which one of the following fishes is a surface feeder?
(a) Rohus                 (b) Mrigals                (c) Common carps                 (d) Catlas
Answer:
(d) Surface feeders fishes 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 waters surface. Catlas possess all there characters, thus is a surface feeder.

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:
(d)
Animal husbandry is scientific management of animal breeding, animals livestock and rearing of animals. (Also, refer to 0.9)

Question 16:
Which one of the following nutrients is not available in fertilisers?
(a) Nitrogen                                               (b) Phosphorus
(c) Iron                                                        (d) Potassium
Answer:
(c) Fertilisers are manufactured by using chemicals. They supply nitrogen, phosphorus and potassium (NPK). They are used for good vegetative growth, (i.e., growth of leaves, branches and flowers). Giving rise to healthy plants is commercially one of the major components for obtaining higher yields, especially in expensive farming practices.
Fertilisers contain much higher amount of nutrients in comparison to the manures and are, therefore, used in very small quantities. Chemically they may be inorganic compounds, (e.gammonium sulphate) or organic compounds (e.g., urea).
On the basis of the availability of nutrients from them, fertilisers are divided into following four groups
(i) Nitrogenous fertilisers These fertilisers supply the macronutrient nitrogen. Examples of nitrogenous fertilisers are Urea (CO(NH2)2); ammonium nitrate (NH4N03).
(ii) Phosphatic fertilisers They are the source of the macronutrient phosphorus. Examples of phosphatic fertilisers are dicalcium phosphate.
(iii) Potassic fertilisers These fertilisers supply potassium which is one of the essential macronutrient of the plants. Examples of potassic fertilisers are: potash or potassium chloride (KCI); Potassium nitrate (KN03).
(iv) Complex fertilisers When a fertiliser contains atleast two or more nutrients (N,P205 and K20), it is called complex fertiliser.
Examples of complex fertilisers are
(i)   Nitrophosphate
(ii)  Ammonium-phosphate
(iii) Urea ammonium phosphate

Question 17:
Preventive and control measures adopted for the storage of grains include
(a) strict cleaning                                      (b) proper disjoining
(c) fumigation                                            (d) All of these
Answer:
(d) Godown, warehouses and stores should be properly cleaned, dried and repaired.
Pathways (alleys) should be provided between the stacks of grain-filled bags, for the periodic inspection, for spraying or for fumigation.
For the large scale storage of grains, the grain silos are used. The silos are big and tall cylindrical structures. They store different stocks of food items at different levels. Silos are provided with outlets at different levels to withdraw the desired stock of grains.
They have built in arrangement for aeration, temperature control, protection from insects, rats, birds and mammals, for fumigation and inspection of their grain stocks.

Short Answer Type Questions

Question 18:
Match the column I with the column II.
15-18
Answer:
The correct matching is
15-18-1

Question 19:
Fill in the blanks
(a) Pigeon pea is a good source of…….
(b) Berseem is an important…….(c)The crops which are grown in rainy season are called…..
(d) ……. are rich in vitamins.
(e) ……. crop grows in winter season.
Answer:
(a) Protein             (b) Fodder                         (c) Kharif crops                (d) Fruits                    (e) Rabi
15-19

Question 20:
What is a GM crop? Name any one such crop which is grown in India.
Answer:
Crops which are been developed by introducing a new gene from any other source, e.g., bacteria or any other organism to obtain the desired character is called 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 21:
List out some useful traits in improved crop.
Answer:
Some of the useful traits in improved crop are
(i) Higher yield The main aim of crop improvement is to improve the productivity of the crop g., grain, vegetables and fodder.
(ii) Improved quality Quality considerations of crop products varies from crop to crop, g., baking quality in wheat, protein quality in pulses, oil quality in oil seeds and preserving quality of fruits and vegetables.
(iii) Biotic and abiotic resistance Under varied situations crop suffers due different stresses, biotic stresses (such as diseases, insects and nematodes) or abiotic stresses (such as drought, salinity, water logging, heat, cold and frost). Crop varieties should be resistant to these stresses, to significantly improve the crop production, g., MUW 318 is a HYV (high yielding variety) of wheat which is released for cultivation in non-tradional areas as Nilgiri and Palini hills and resistant to all the rusts.
(iv) Changes in maturity duration In some of the short duration crops, early maturing varieties can make the crop fit into double and multiple cropping system. This will also reduce the crop’s cost of production.
(v) Desirable agronomic traits If we develop those varieties of crops which contain desired agronomic traits then it will help in setting higher production, g., breeding for resistance to red rot has led to sugarcane varieties such as Co 975 and Co 62399 which increase cane production in problem areas.
(vi) Wider adaptability If we develop those varieties of crops which have wider adaptability, then it will help in stabilising the crop production under different environmental conditions, g.,ICPH 8 is a hybrid pigeon pea plant which takes a short duration to mature, escapes diseases such as fusarium wilt and sterility mosaic and yields 30 to 40 per cent more than the popular breed.

Question 22:
Why is organic matter important for crop production?
Answer :
Organic manures help to improve the physical properties of soil, reduce soil erosion, increase the moisture holding capacity of soil and are low cost nutrient carriers.
Use of biological waste material is a way of re-cycling the farm waste. Manures protect our environment from synthetic chemicals, (i.e., fertilisers).
(Also, refer to Q. 8)

Question 23:
Why is excess use of fertilisers detrimental for environment?
Answer:
Fertilisers should be applied scientifically, in terms of proper dose, time, pre and post application precaution for their complete utilisation.
Excess fertilisers usually get washed away through irrigation, rainfall, etc. and pollute rivers, lakes, streams causing algal bloom, toxicity and eutrophiciation.

Question 24:
Give one word for the following.
(a) Farming without the use of chemicals as fertilisers, 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) Sustainable farming                         (b) Mixed cropping
(c) Inter cropping                                    (d) Crop rotation
(e) Weeds                                                  (f) Pathogen

Question 25:
Match the following column I and II

15-25-1
Answer:
The correct matching is
15-25-2

Question 26:
If there is low rainfall in a village throughout the year. What measures will you suggest to the farmers for better cropping?
Answer:
Suggestion for farmers
(i) Practice farming with drought resistant and early maturing varieties of crops.
(ii) To enrich soil with more humus content as it increases the water-holding capacity and retains water for longer duration.

Question 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:
These are as given
15-27

Question 28:
Define the term hybridisation and photoperiod.
Answer:
Hybridisation The cross between two unidentical plant to give rise to a new variety with desired trait is called hybridisation. (Also, refer to Q. 5)
Photoperiodism the effect of light hours or daily duration of light exposure on the flowering of plant is called photoperiodism. On the basis of light duration or dark exposure, plants one classified as short day plant (requires short photoperiods) or long day plants (requires long exposure of light).

Question 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….
(e) Wheat, gram, pea, mustard are……crops
Answer:
(a) Growth                                          (b) June-July                               (c) October-November
(d) Kharif crops                                 (e) Rabi crops

Question 30:
Cultivation practices and crop yield are related to environmental condition. Explain.
Answer:
All crops do not grow under same environmental conditions. Thus, their cultivation practices and yield, are related to conditions of environment. Like high humidity, duration of sunlight, shorter duration of sunlight, high temperature, low temperature, etc, e.g., Apple can not be grown in plains because it require several days of low temperature exposer.

Question 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) 16                                         (b) Carbon and Oxygen                       (c) Hydrogen
(d) essential                             (e) 6, macronutrients                           (f) 7, Micronutrients

Question 32:
Differentiate between compost and vermicompost?
Answer:
Difference between compost and vermicompost are
15-32

Question 33:
Arrange these statements in correct sequence of preparation of green manure.
(a) Green plants are decomposed in soil.
(b) Green plants are cultivated forpreparing manure or cropplants parts are used.
(c) Plants are ploughed and mixed into the soil.
(d) After decomposition it becomes green manure.
Answer:
(a) Green plants are cultivated for preparing manure or crop plants are used.
(b) Plants are ploughed and mixed into the soil.
(c) Green plants are decomposed in soil.
(d) After decomposition it becomes green manure.

Question 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 variety A. mellifera are
(i)   It is sting less.
(ii)  It has high honey collection facility.
(iii) It stays in given beehive for long periods and breeds very well.

Question 35:
In agricultural practices, higher input gives higher yield. Discuss how?
Answer:
In agricultural practices, higher inputs give higher yield. This means higher money inputs to raise the yield. Financial conditions of the farmers allow them to take up different farming practices and technologies. The farmer’s purchasing capacity for input decides cropping system and production practices.

Question 36:
Discuss the role of hydridisation in crop improvement.
Answer:
Hybridisation
The crossing between genetically dissimilar plants to produce a new variety known as hybrid is called hybridisation. Crossing may be between two different varieties . (intervarietal cross-breeding), between two different species of the same genus (interspecific cross-breeding) and between different general (intergeneric cross-breeding). The most common type of breeding is inter varietal.
In India crops are grown in diverse types of soil and different climatic conditions by poor to progressive all types farmers. Keeping climatic factor, input application, disease and pest resistance, quality and adaptability in mind, etc., a large number of varieties have been developed in India. These varieties are high yielding and resistant to diseases and pests, they have better quality and early to late maturing time.
15-36

Question 37:
Define
(i) Vermicompost                          (ii) Green manure
(iii) Biofertiliser
Answer:
(i) Vermicompost is a manure rich in pulverised organic matter and nutrients. Vermicompost is prepared by using earthworms to hasten the process decomposition of plants and animals refuses. Earthworm is physically is an aerator, crusher and mixer, chemically a degrader and biological stimulator of decomposition. Most common species of earthworm used for decomposition are Dichogaster bolani.
(ii) Green manure is prepared by decomposition of green plants in field itself. It helps in enriching the soil in nitrogen and phosphorus. Organic matter for improving hydration, aeration and word structure of soil. It provides protection against erosion and leaching. g., sunhemp is grown in fields, mulched by ploughing and allowed to decompose in the field for the preparation of green manure.
(iii) Biofertiliser are living organism used as fertiliser to supply the nutrients to crop plants. g., nitrogen fixing blue green algae, nitrogen fixing bacteria, which fix atmospheric nitrogen in soil, rice fields, are called as biofertiliser.

Question 38:
Discuss various methods for weed control.
Answer:
Methods of weed control are
(i) Mechanical Methods The process of removing the weeds from crop fields is called weeding. It is done by following methods.
(a) Weeds may be pulled out by hand. Ploughing helps in removing large number of the weeds.
(b) Before sowing or transplantation weeds are removed by using a big comb called Harrow cannot be used in standing crops because it will also uproot the crop plants.
The weeds which appear during the growth of crop plants are removed manually by using a trowel (Khurpa).
(ii) Cultural Methods They include the following methods, proper bed preparation timely sowing of crops, inter cropping and crop rotation.
(iii) Chemical Methods Chemical weed killers, called herbicides or weedicides, are sprayed on weeds to destroy (kill) them. This is called chemical control of weeds. Some common examples of weedicides are (i) 24-D (2, 4-Dichlorophenoxy acetic acid) (ii) atraxine (iii) fluchloralin (iv) isoproturon.
(iv) Biological Control Biological control of weeds involves the deliberate use of insects or some other organism which consume and specifically destroy the weed plants.
The best Indian example of biological control is eradication of prickly pear cactus (Opuntia) by using the cochineal insects in Maharashtra and Tamil Nadu.
Generally, a combination of one or more of these weed control methods are employed to get good results. Aquatic weeds are controlled by the fish grass carp.

Question 39:
Differentiate between the following
(i) capture fishery and culture fishery
(ii) mixed cropping and intercropping
(iii) bee keeping and poultry farming
Answer:
15-36

Question 40:
Give the merits and demerits of fish culture?
Answer:
Merits of Fish Culture
(i)   Quality and quantity of desired fishes can be increased.
(ii)  Fishes are cheap source of animal protein thus increases quality of food.
(iii) Export of fishes bring foreign currency.
Demerits of Fish Culture
(i)  It is a threat to biodiversity.
(ii) Only economically important and valued fishes will be cultured.

Question 41:
What do you understand by composite fish culture?
Answer:
Composite fish culture system is adopted for intensive fishing.
Characteristics of Composite Fish Culture
(i)   Both local as well as imported fish species can be used in such systems.
(ii)  A combination of five or six fish species is used in a single fish pond.
(iii) These species have different feeding habits.
(iv) These species are selected so that they do not compete for food among them having different food
habits.
e.g., Catlas surface feeders.
Rohu feed in middle zone of the pond.
Mrigals bottom feeders.
Common carps bottom feeders.
Grass carps weed feeders.
Advantages
All the food available in the pond is utilised.
There is no competition for food.
There is increase in the fish yield from the pond.          ,
Disadvantage of Composite Fish Culture
Lack of availability of good quality fish seeds.

Question 42:
Why bee keeping should be done in good pasturage?
Answer:
The quality and taste of honey depends upon the flora, pasturage or orchards available for the nectar and pollen collection. That is bee keeping should be done in good pasturage. Pasturage/orchard flora of honey bees include a variety of flowering plants such as mango (Aam), coconut (Narial), almond (Badam) tamarind (Imli), ber, berseem, litchi, cotton, shishame, apple, mahua, coriander, cashew, coffee, rubber plants, guava, sunflower, neem, etc.

Question 43:
Write the modes by which insects affect the crop yield.
Answer:
Some common insect pests of stored grain and their mode of infection are
(i) Gram dhora or Pulse beetle (Callosobruchus maculatus) Its grubs, damage the stored gram
(ii) Rice weevil (Sitophilus oryza) Both grub and beetle (adult) damage rice
(iii) Khapra or Wheat weevil (Trogoderma granarium) Infests stored wheat
(iv) Grain and flour moth {Sitotroga cerealella) Its caterpillars bore into grains of rice, wheat, barley,
maize and jowa
(v) Rust red flour beetle (Tribolium castaneum) Both larvae and adult damage flour and flour products
(vi) Rice moth (Corcyra cephalonica) Larvae damage rice and maize
(vii) Lesser grain borer (Rhizopertha dominica) Both grub and adult (beetle) damage the grains, reducing them to perforated shells

Question 44:
Discuss why pesticides are used in very accurate concentration and in very appropriate manner?
Answer:
Pesticides should be used in accurate concentration as they are very harmful to environment. Pesticides one non-biodegradable and can be accumulated in the trophic level. The environmental impact of pesticides consists of the effects of pesticides on non-target species. Over 98% of sprayed insecticides and 95% of herbicides reach a destination other than their target species, because they are sprayed or spread across entire agricultural fields.            .
Runoff can carry pesticides into aquatic environments while wind can carry them to other fields, grazing areas, human settlements and undeveloped areas, potentially affecting other species. Other problems emerge from poor production, transport and storage practices.

Question 45:
Name two types of animal feed and write their functions.
Answer:
The dairy cattle is given a balanced ration, which contains all nutrients in proportionate amounts. A ration is the amount of food which is given to the animal during a twenty-four hour period.
The animal feed includes two types of substances
(i)  Roughage It largely contains fibres such as green fodder, silage, hay (straw of sereals) and legumes, (e.g., berseem, lucerne, cow pea and agathi)
(ii) Concentrates The concentrates used in feed of cattle and bufalloes are a mixture of substances which are rich in one or more of the nutrients, g., cotton seeds, oil seeds, • grains of maize, oats, barley jowar, bajra, gram and their byproducts such as wheat bran, rice bran (polish), gram husk, oil seed cakes and molasses.

  1. Green fodder and dry grasses (roughage) = 15 to 20 kg
  2. Grain mixture (concentrates) = 4 to 5 kg
  3. Water 30 to 35 litres.
    Besides above mentioned nutritious food material, dairy animals require certain additive feeds, promote the growth of the animals which contain antibiotic, minerals, and hormones, facilitate good yield of milk and protects them from diseases.

Question 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 in adaptibility, what method will be employed?
Answer:
If poultry birds are large in size, it will becomes very difficult to manage their summer adaptability with them.
The programmes of cross breeding between Indian (indigenous) and foreign (exotic) breeds for variety improvement are focused to develop new varieties for the desirable traits some of them are
(i)  Quantity and quality of chicks
(ii) Dwarf broiler parent for commerical chick production for summer adaptation capacity/tolerance to high temperature
(iii) Low maintenance requirement
(iv) Improvement in hen housed for egg production and reduction in the size of the layer with ability to utilise more fibrous, cheap diet formulations using agricultural byproducts.

Question 47:
Suggest some preventive measures for the diseases of poultry birds.
Answer:
(i) Care for the Layers There are following two distinct phases in the life of a layer
(a) Growing Period The first phase of the life of poultry, (i.e., the layer) is growing period (upto sexual
maturity). During this period the chickens are called The growers require enough space. Overcrowding tends to suppress their growth. The feed is given in a restricted and calculated manner.
(b) Laying Period The period from sexual maturity till the end of egg laying is called laying period and the chickens are known as eggers or The layers require enough space and adequate lighting.
Light’s intensity and its duration has favourable effect on the laying output of the hens. Feed with vitamins, minerals and micronutrients also influence hatching ability of eggs.
(ii) Care for the Broilers The housing, nutritional and environmental requirements of broilers are different from layers. Conditions provided have to be favourable for the fast growth and low mortality of broilers. The ratio for broilers is protein rich with sufficient fat. In the poultry feed, the contents of vitamin A and K are kept high.

Question 48:
Figure shows the two crop fields [Plots A and B] have been treated by manures and chemical fertilisers 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?
15-48
Answer:
(i)   Plot B refers to chemical fertilisers which give short-term benefits because they are nutrient specific. The continuous use of fertilisers in an area destroy soil fertility so there is gradual decrease in yield after sometime.
(ii)  Manures help in enriching soil with nutrients and organic matter and increase the soil fertility. They also improve the soil structure. The plot A demonstrates the trend that the addition of manures into the soil have long term benefits in terms of high yield.
(iii) Manures are natural ways of enriching the soil whereas fertilisers are commercially produced plant nutrients. They do not have organic matter like in manure to replenish the soil with useful microbes. Therefore, in plot A manures give high yield while plot B gives high yield for a short time and then it decreases.

Question 49:
Complete the crossword puzzle figure.
15-49
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:
15-49s

All Chapter NCERT Exemplar Problems Solutions For Class 9 Science

—————————————————————————–

All Subject NCERT Exemplar Problems Solutions For Class 9

*************************************************

I think you got complete solutions for this chapter. If You have any queries regarding this chapter, please comment on the below section our subject teacher will answer you. We tried our best to give complete solutions so you got good marks in your exam.

If these solutions have helped you, you can also share ncertexemplar.com to your friends.

Leave a Comment

Your email address will not be published.