Question

What is echinodermata?

Answer 1

Echinodermata is an interesting animal phylum which includes only marine members. Present day echinoderms arise from biradially symmetrical larvae but are all pentaradially symmetrical.

Explanation:

Echinodermata means spiny skin. Member of this marine animal phylum possesses an endoskeleton that surrounds and protects the body. Endoskeleton is made of calcareous plates and spines arranged in mosaic pattern.

Echinodermata is bottom dwelling, radially symmetrical animal. There is no trace of cephalisation. Embryonic development is deuterostomial.

There is no physical distinction between sexes but sexes are separate. Eggs hatch in bilaterally symmetrical larvae which metamorphoses in pentaradially symmetrical adults.

There is oral and aboral surfaces in the body. There is a water vascular system which terminates in paired rows of tube feet.

Phylum echinodermata is divided in different class: sea lily, sea cucumber, sea star, sea urchin, etc are all members of echinodermata.