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Carnegie Stage   Figure

3-cell embryo

3-cell embryo

TEM of a stage 2, 3-cell embryo in vitro, 44 hours post-insemination. All of the blastomeres have nuclei but the cut is through only one with a nucleolus. Clear vacuoles have increased in number and polar body 1 is in the subzonal space.

From: Sathananthan et al., 1986. Reproduced with permission of the publisher, Greenwood Publishing Group.


Keywords: blastomere, nucleolus, nucleus, polar body, stage 2 embryo, subzonal space, three-cell embryo, vacuole(s)


Source: The Virtual Human Embryo.