3. What is a starfish?

Starfish belong to a group of animals called echinoderms which includes sea cucumbers, brittle stars, feather stars and sea urchins. These animals are found only in the sea. As their common name implies, starfish have a roughly star shaped body; that is, their body comprises arms or rays which project out from a central disc. The mouth is located in the centre of the underside of the disc. A large part of the interior (coelom) of the starfish is fluid filled. Within this structure are to be found the stomach, digestive organs (caeca), sex organs (gonads) and primitive nervous system.

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