Protostoma

Quick meaning: Protostoma is a noun meaning (embryology, obsolete) Synonym of blastopore.

Meaning

(embryology, obsolete) Synonym of blastopore.

More Meanings

1. (zoology) In nematodes, a particular division of the stoma (mouthlike opening).

Example Sentences

The protostoma with its wall—the protorhabdion—is the major part of the stoma.

Conventionally, the stoma is divided into three parts: the anterior chamber or cheilostoma, the middle or protostoma, and the posterior or telostoma.

The opening of this, the protostoma, becomes elongated, taking on an elliptical shape, and then it narrows in the middle, its outline becoming that of a dumb-bell.

It is frequently stated by critics of the protostoma hypothesis that it involves a reversal of dorsal and ventral sides during the evolution of Vertebrates from their invertebrate ancestors but it will be gathered from what has been said that this criticism rests on a misunderstanding.

Word Forms

• protostomata

Synonyms for protostoma

Depending on context, synonyms include blastopore.

Related Words

Related dictionary entries include protostome, proteostome, protostomian, gonoblastidium, pseudostome, blastula.

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