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Assertion : Earthworm are known are know...

Assertion : Earthworm are known are known as friends of farmers
Reason : Earthworms make burrows in the soil and make the soil porous, which helps in repiration and penetration of developing plant roots.

A

If both (A) and (R) are true but (R) is not the correct explanation of (A).

B

If both (A) and (R) are true and (R) is the correct explanation of (A).

C

If (A) is true but (R) is false.

D

If both (A) and (R) are false.

Text Solution

Verified by Experts

The correct Answer is:
A
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Earthworms are known as ‘farmer’s friends’. Why?

Assertion: The earthworms are referred to as the farmer's friend. Reason : Earthworm help in the breakdown of complex organic matter as well as in loosening of the soil.

Assertion : Repeated muscle expansions and contractions make the earthworm move through the soil. Reason : Earthworms help to make the soil fertile, loose and porous.

Assertion : Birds are with pneumatic bones. Reason : Air sacs make the bones lighter which helps in the flight of the birds.

First read a passage and then answer the questions following that passage. Soil scientists have shown that the soil teems with millions of living things, many of them useful, others harmful. The living things which are useful include earthworms and various kinds of bacteria. Earthworms loosen the soil and so enable air and water to enter it. Bacteria, which are microscopic living things break down dead plants and animals and make humus, or take nitrogen from the air and change it into substances that plants use. The living things that do harm include other bacteria and fungi which cause diseases. Other harmful things are pests such as wire worms which feed on the roots of grass and other plants. While the farmer can usually keep weeds in check by careful cultivation, this alone may not protect his crops from insects, pests and diseases. Nowadays, however, he is much better able to control these enemies. He may plant. specially resistant types of seeds or he may keep the pests and diseases in check with chemicals. With better seeds farmers have been able to increase their crop yield . They can grow crops that ripen more quickly and have a stronger resistance to disease, frost or drought. Scientists who study soil believe that

First read a passage and then answer the questions following that passage. Soil scientists have shown that the soil teems with millions of living things, many of them useful, others harmful. The living things which are useful include earthworms and various kinds of bacteria. Earthworms loosen the soil and so enable air and water to enter it. Bacteria, which are microscopic living things break down dead plants and animals and make humus, or take nitrogen from the air and change it into substances that plants use. The living things that do harm include other bacteria and fungi which cause diseases. Other harmful things are pests such as wire worms which feed on the roots of grass and other plants. While the farmer can usually keep weeds in check by careful cultivation, this alone may not protect his crops from insects, pests and diseases. Nowadays, however, he is much better able to control these enemies. He may plant. specially resistant types of seeds or he may keep the pests and diseases in check with chemicals. With better seeds farmers have been able to increase their crop yield . They can grow crops that ripen more quickly and have a stronger resistance to disease, frost or drought. Farmers are always careful

First read a passage and then answer the questions following that passage. Soil scientists have shown that the soil teems with millions of living things, many of them useful, others harmful. The living things which are useful include earthworms and various kinds of bacteria. Earthworms loosen the soil and so enable air and water to enter it. Bacteria, which are microscopic living things break down dead plants and animals and make humus, or take nitrogen from the air and change it into substances that plants use. The living things that do harm include other bacteria and fungi which cause diseases. Other harmful things are pests such as wire worms which feed on the roots of grass and other plants. While the farmer can usually keep weeds in check by careful cultivation, this alone may not protect his crops from insects, pests and diseases. Nowadays, however, he is much better able to control these enemies. He may plant. specially resistant types of seeds or he may keep the pests and diseases in check with chemicals. With better seeds farmers have been able to increase their crop yield . They can grow crops that ripen more quickly and have a stronger resistance to disease, frost or drought. The farmers today can also select seeds

First read a passage and then answer the questions following that passage. Soil scientists have shown that the soil teems with millions of living things, many of them useful, others harmful. The living things which are useful include earthworms and various kinds of bacteria. Earthworms loosen the soil and so enable air and water to enter it. Bacteria, which are microscopic living things break down dead plants and animals and make humus, or take nitrogen from the air and change it into substances that plants use. The living things that do harm include other bacteria and fungi which cause diseases. Other harmful things are pests such as wire worms which feed on the roots of grass and other plants. While the farmer can usually keep weeds in check by careful cultivation, this alone may not protect his crops from insects, pests and diseases. Nowadays, however, he is much better able to control these enemies. He may plant. specially resistant types of seeds or he may keep the pests and diseases in check with chemicals. With better seeds farmers have been able to increase their crop yield . They can grow crops that ripen more quickly and have a stronger resistance to disease, frost or drought. Nowadays it is possible to reduce the loss caused by pests and harmful bacteria

First read a passage and then answer the questions following that passage. Soil scientists have shown that the soil teems with millions of living things, many of them useful, others harmful. The living things which are useful include earthworms and various kinds of bacteria. Earthworms loosen the soil and so enable air and water to enter it. Bacteria, which are microscopic living things break down dead plants and animals and make humus, or take nitrogen from the air and change it into substances that plants use. The living things that do harm include other bacteria and fungi which cause diseases. Other harmful things are pests such as wire worms which feed on the roots of grass and other plants. While the farmer can usually keep weeds in check by careful cultivation, this alone may not protect his crops from insects, pests and diseases. Nowadays, however, he is much better able to control these enemies. He may plant. specially resistant types of seeds or he may keep the pests and diseases in check with chemicals. With better seeds farmers have been able to increase their crop yield . They can grow crops that ripen more quickly and have a stronger resistance to disease, frost or drought. The living things that do harm

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