Question

How does the earthworm move?

Answer 1

Hint: The cylindrical body of an earthworm is made up of many segments. Even though earthworms do not possess limbs or appendages, they do have specialized structures within their body. When earthworms move on soil, they leave behind thin trails in the form of tunnels. This movement helps in aerating the soil.

Complete answer:
- The body of an earthworm is segmented into many small rings. An average-sized earthworm can possess 100-150 segments. Their bodies have been adapted to survive on the ground and underground.
- Each segment on the worm contains small bristle-like structures called setae, that help the earthworm to form a grip in the soil.
- There are two types of muscles in an earthworm – circular and longitudinal. Circular muscles are present on each of the segments and the longitudinal muscles run throughout the length of the body.
- The circular muscles contract, causing the body to become longer and thinner. They use the setae to anchor their body in the soil. When the longitudinal muscles contract, the body pulls forward. They withdraw the front setae and use the back setae now to anchor their rear ends. After this the circular muscles contract again and the process is repeated.

Note: When an earthworm moves through the soil, it creates tiny channels or burrows. This burrowing helps in aeration of the soil and also helps water and minerals to flow easily. The earthworms also produce wastes on the soil which act as a natural fertilizer. The waste is a source of phosphorus, nitrogen, calcium, and magnesium.