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Medical Term:


Pronunciation: blas′tō-sist

Definition: The modified blastula stage of mammalian embryos, consisting of the embryoblast or inner cell mass and a thin trophoblast layer enclosing the blastocystic cavity or blastocele.

Synonym(s): blastodermic vesicle

[blasto- + G. kystis, bladder]

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.