Somewhat flattened, globular echinoderms, having thin, brittle shells of calcareous plates. They are useful models for studying FERTILIZATION and EMBRYO DEVELOPMENT.

The order Clypeasteroida.

Synonyms: Urchin, Sea, Sand-Dollar, Dollars, Sand, Urchins, Sea, Sea Urchins, Clypeasteroida, Sand Dollar, Sea Urchin, txid31186, Clypeasteroidas, Echinoidea, txid7625, Sand-Dollars, Sand Dollars, Echinoideas, Dollar, Sand

Instance information

comment

72 ,general; prefer specifics; sea urchin eggs = OVUM (IM) + SEA URCHINS (NIM) if merely test organism

identifier

D012617

Instance relations

Types