NEET BIOLOGY

Detailed explanation-1: -echinoderm, any of a variety of invertebrate marine animals belonging to the phylum Echinodermata, characterized by a hard, spiny covering or skin.

Detailed explanation-2: -Echinoderm means spiny skin. If we break the word down echino = spiny and derm= skin, so these animals are spiny-skinned. Sea stars and their cousins are part of a group of spiny-skinned animals. Sea Stars: Most sea stars have five arms.

Detailed explanation-3: -Structure and Function of Echinoderms. Echinoderms are named for their “spiny skin.” However, the spines aren’t on their skin. They are part of the endoskeleton. The endoskeleton consists of calcium carbonate plates and spines, covered by a thin layer of skin.

Detailed explanation-4: -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.

Detailed explanation-5: -: having a skin covered with knobs, tubercles, or spines.