Question

How do the longitudinal muscles and the circular muscles help the earthworm move through its environment?

1) By contracting and anchoring the setae
2) By expanding and contracting the body segments
3) By secreting mucus to reduce friction
4) By using its bristles to push against the ground

Answer 1

Earthworms move through contracting circular muscles to lengthen and contracting longitudinal muscles to shorten their body segments, utilizing setae to anchor and help push themselves along in the soil.

Step-by-step explanation:

The longitudinal muscles and circular muscles in earthworms facilitate their movement through an environment via a process known as peristalsis, which is a wave-like muscular contraction. When the circular muscles contract, they cause the body segments to expand, increasing the length of the worm and extending the anterior end forward. Then, the longitudinal muscles contract, shortening the segments and pulling the posterior portion of the body to catch up. Additionally, earthworms have small bristles called setae that they use to anchor themselves in the soil, enabling effective contraction and elongation during movement.