protostome

/proh-tuh-stohm/US // ˈproʊ təˌstoʊm //

原生质体,原生动物,原生生物体,原生动物组

Definitions

n.名词 noun

1
Zoology.
- : any member of the lower invertebrate phyla in which the mouth appears before the anus during development, cleavage is spiral and determinate, and the coelom forms as a splitting of the mesoderm.