NEET BIOLOGY

Detailed explanation-1: -Echinoderms are named for the spines or bumps covering the outer surface of the bodies of many of them (Greek root word echino-meaning spiny; Latin root word-derm meaning skin). Examples of echinoderms include sea stars, sea urchins, sea cucumbers, brittle stars, and feather stars (Fig.

Detailed explanation-2: -Projections from the skeleton, sometimes resembling spikes, which are typical of echinoderms, give the phylum its name (from Greek echinos, “spiny, ” and derma, “skin”).

Detailed explanation-3: -These spines offer protection from many would-be predators. The spines are joined to the skeleton of the animal, called the “test, ” in a form of ball-joint.