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Carnegie Stage   Figure

A section through the inner cell mass (embryoblast) of an unexpanded embryo

A section through the inner cell mass (embryoblast) of an unexpanded embryo

Light microscopic view of a stage 3 embryo in vitro through the inner cell mass (ICM). 145 hours post-insemination. The blastocyst is unexpanded.

BC = blastocystic cavity (blastocoele)

From: Lopata et al., 1982. Reproduced with permission of the publisher, John Wiley & Sons.


Keywords: blastocyst(s), inner cell mass (embryoblast), unexpanded embryo


Source: The Virtual Human Embryo.