EVERYDAY SCIENCE

Detailed explanation-1: -Examples of echinoderms include sea stars, sea urchins, sea cucumbers, brittle stars, and feather stars (Fig. 3.83). Although they may appear very different, echinoderms all have two major defining characteristics that set them apart from all other animals: a water vascular system and five-sided radial symmetry.

Detailed explanation-2: -Echinoderms are a phylum of marine invertebrates that include starfish, brittle stars, sea cucumbers, sea urchins, sand dollars, and crinoids. They are one of the most diverse groups of marine invertebrates and play important ecological roles from the near-shore environment to the deep seas.

Detailed explanation-3: -Sand Dollars are members of the phylum Echinodermata, and their relatives include sea cucumbers, sea stars and sea urchins among others. Characteristics of this phylum include spiny skin, tube feet for locomotion, and radial symmetry.

Detailed explanation-4: -Sand dollars and sea stars are in a group of invertebrates called echinoderms that means spiny skin. They are the only invertebrates with an internal skeleton and internal cavity, which allows for the development of internal organs.

Detailed explanation-5: -Fast Facts. The echinoderms (Greek for spiny skin) include sea stars, sea urchins, feather stars, brittle stars and sea cucumbers. All are found in the marine environment in a range of habitats from intertidal surf beaches to the deepest oceans.