MOVEMENT IN EARTHWORM
• An earthworm is an invertebrate.
• It has a long, tube-like body.
• It has no bones.
Tube-like body of an earthworm
• Earthworms live in moist soil which contains organic matter.
• Earthworms do not have eyes or ears but they have a mouth and are sensitive to heat, light and touch.
• This adaptation is important for the survival of an earthworm.
• In winter, an earthworm travels deep in the soil to avoid the frost.
• In summer, an earthworm travels deep into the soil in order to avoid dehydration.
• Its body shape is maintained by the fluid present inside its body, just like that of a water-filled balloon.
• An earthworm's body is made up of several parts called segments.
• It moves by lengthening and shortening these segments.
• It extends the front part of the body, keeping the rear end fixed to the ground.
• Then it fixes the front part and pulls the rear end.
• Thus, an earthworm moves by stretching its front section through the soil and then pulling its hind section up.
Movement in an earthworm
• Its body secretes a slimy substance which helps in the movement.
• The segments also have tiny, hair-like bristles, which help the earthworm to grip the surface and pull its body forward.
• The tiny bristles cover the body of the worm and enable the worm to grip the soil as it passes through.
• This really helps the worm moves through the soil quickly without slipping.