Basic Science Solutions for Class 8 Science Chapter 1 Food Production are provided here with simple step-by-step explanations. These solutions for Food Production are extremely popular among class 8 students for Science Food Production Solutions come handy for quickly completing your homework and preparing for exams. All questions and answers from the Basic Science Book of class 8 Science Chapter 1 are provided here for you for free. You will also love the ad-free experience on Meritnation’s Basic Science Solutions. All Basic Science Solutions for class 8 Science are prepared by experts and are 100% accurate.

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Agriculture (ager means field and culture means cultivation in latin) is the science that deals with crop production for human use.

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Rubber and coffee are examples of plantation crops.

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Weeds are unwanted plants that grow along with the crops and compete with the crops for water, minerals and sunlight.

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Following ways are used to remove weeds:

(a) Manually
(b) By using tools like trowel, hoe or rake
(c) Spraying weedicide

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Pests are the organisms that attack the crops and damage them. Examples: Rodents or insects

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Animal proteins are better than plant proteins because they contain certain essential amino acids that plant proteins lack. Also, animal proteins can be more easily digested by us.

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Kharif crops are sown during the monsoon.

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Animal husbandry is the practice of rearing of animals for food and other purposes.

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Temperature and humidity are the two things that have to be controlled in a cold storage.

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(a) Crop rotation is a good agricultural practice because it maintains the nutrition of the soil. In this method, different crops are grown in succession in the same field.
(b) Pulses are alternated with crops like wheat or paddy because these crops consume lot of nitrogen from the soil. The roots of pulses form an association with nitrogen-fixing bacteria and convert the atmospheric nitrogen into ammonia, which is used by plants. When the plants die, large amount of nitrogen fixed by them remains in the soil and becomes available for the next crop.

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(a) Green manure refers to the plants that are grown to produce manure. Examples of green manure include black gram, cluster bean and cowpea.
(b) Compost is formed when manure is produced in the presence of microorganisms that act on the waste matter covered in pits or in open. Waste that is decomposed by microorganisms include crop residue, animal dung and sludge.

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(a) Biological control of weeds and pests refers to a method in which a biological enemy of the weeds and pests is introduced in the field. This organism kills the weeds and pests. Other way of biological control is to develop disease-resistant varieties of crops.
(b) Biological control is better than the use of weedicides and pesticides as it does not harm the health of the human beings, who consume the crops. Weedicides and pesticides are poisonous and non-biodegradable chemicals that are absorbed by plants. Such plants allow these chemicals to enter our body.

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Root nodules are the swellings that are found in the roots of leguminous plants. These nodules are formed by nitrogen-fixing bacteria that live in leguminous roots. These nodules help in converting atmospheric nitrogen into compounds that could be used by plants.

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Surface irrigation refers to the different ways of irrigation in which water is allowed to run over the field. There are two ways of surface irrigation:
(a) Furrow irrigation: Here, crop is planted on ridges and water is allowed to run through furrows between the ridges.
(b) Basin irrigation: Here, water is contained in the whole field by making bunds all around it.

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Advantages of using chemical fertilisers:
(a) They provide specific nutrients that are not present in the soil.
(b) They are easy to store and transport as they are compact.
(c) They are water soluble; therefore, they are readily absorbed by plants.

Disadvantages of using chemical fertilisers:
(a) They make the soil more prone to erosion as they do not provide humus.
(b) They can harm soil fertility by making it more acidic or alkaline.
(c) They may cause eutrophication by mixing in water bodies.

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Nitrogen cycle:
Nitrogen present in the air is converted into ammonia or other compounds of nitrogen that can be used by the plants through certain nitrogen-fixing bacteria present in the soil. These compounds are used by plants to make proteins from where they pass on to the animals, who consume these plants.
When plants and animals die, the nitrogen compounds present in their bodies are converted into ammonia by microorganisms. The ammonia is ultimately converted to nitrates by bacteria. Nitrogen is returned to the atmosphere by the bacteria that break down nitrogen compounds to get energy and release nitrogen.

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Sources of irrigation in India:

(a) Dams: Dams are constructed across rivers. Water is carried through them by canals to different parts that are deprived of water. Permanent and inundation canals are used to carry water to different fields.
(b) Wells: They are used to tap groundwater. Electrical tube wells are now used to pump water from these wells for irrigation.
(c) Groundwater: Over 50 per cent of water used in irrigation is groundwater. In many parts of north India, groundwater is used as an additional source of irrigation.

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1. The practice of growing fruit, vegetables, flowers and ornamental plants are horticulture.
2. The process of using the vapours of a chemical to disinfect a place and get rid of pests is called fumigation.
3. A buffer stock of grains is maintained to provide food during emergencies.
4. A mutually beneficial association between two organisms is called symbiosis.
5. Seeds have to be sown at the right depth and with adequate spaces in between.
6. Biological control is a method of controlling weeds or pests by using their natural enemies.
7. A fallow field is one that is left uncultivated for one or more seasons.

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Following activities are involved in growing a crop:

(a) Ploughing
(b) Levelling
(c) Manuring



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(c) Winnowing

Winnowing is the process of removing chaff from the grain.

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(d) can harvest, thresh and winnow

A combine refers to a machine that can harvest, thresh and winnow.

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(a) Rice

Rice is not a rabi crop. It is sown during monsoon; therefore, ​it is a kharif crop.

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(b) nitrogen fixation

The process of converting atmospheric nitrogen into nitrogenous compounds is called nitrogen fixation.

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(a) drip irrigation

Drip irrigation is a method in which emitters let out a trickle of water near the roots of the plants.

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(d) between 0°C and 4°C

The temperature in a cold storage is maintained between 0°C and 4°C.

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(a) Rice

The seedlings of the rice are sown in nurseries and then, they are transplanted to the crop fields.

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(a) pea

Roots of peas contain nodules with nitrogen-fixing bacteria.

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(d) jute

Jute is not a rabi crop.

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(a) and (c)

Jowar and bajra are millets that require very little water.

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(b) winnowing

Winnowing is done after the crops are gathered.

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(c) cowpea

Cowpea is an example of green manure.



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