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Carnegie Stage   Figure

Area between the abstracted second polar body

Area between the abstracted second polar body

High power TEM of a stage 1a embryo in vitro in the area between the abstracted second polar body (PB2) and the embryo, three hours after insemination (original magnification x19,600). Released cortical granules are in the form of spherical blebs (small arrowheads) on either side of the cytoplasmic constriction. A few cortical granules in the polar body are releasing their contents into the subzonal space (large arrowhead).

Ib = interbody
M = dense mitochondrion
Mt = microtubules
Mv = microvilli

From: Sathananthan and Trounson, 1982. Reproduced with permission of the publisher, John Wiley & Sons.


Keywords: abstracted second polar body, cortical granule(s), cytoplasmic constriction, dense mitochondria, interbody, microtubules, microvilli, second polar body, stage 1a embryo


Source: The Virtual Human Embryo.