Question

name the organ for locomotion in starfish and sea urchin​

Answer 1

In sea stars, water enters the system through a sieve-like structure on the upper surface of the animal, called the madreporite. ... Each arm of a sea star has one such groove on its underside, while, in sea urchins, they run along the outside of the body.

Answer 2

The water vascular system is a hydraulic system used by echinoderms, such as sea stars and sea urchins, for locomotion, food and waste transportation, and respiration. The system is composed of canals connecting numerous tube feet.