NEET BIOLOGY

Detailed explanation-1: -An echinoderm (/ɪˈkaɪnəˌdɜːrm, ˈɛkə-/) is any member of the phylum Echinodermata (/ɪˌkaɪnoʊˈdɜːrmətə/). The adults are recognisable by their (usually five-point) radial symmetry, and include starfish, brittle stars, sea urchins, sand dollars, and sea cucumbers, as well as the sea lilies or “stone lilies".

Detailed explanation-2: -Share. Sand dollars are a type of invertebrate related to the sea urchins, sea stars, and sea cucumbers – together known as the echinoderms.

Detailed explanation-3: -Echinodermata (echinoderms), class: Echinoidea (sea urchins, heart urchins & sand dollars)

Detailed explanation-4: -Introduction: Starfish, sand dollars, and sea urchins all belong to a group (phylum) of invertebrates known as echinoderms. The word “echinoderm” means spiny skin, which describes most of the organisms in this phylum.

Detailed explanation-5: -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.