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Carnegie Stage   Figure

Cytoplasmic organelles

Cytoplasmic organelles

Very high power TEM of a late stage 1b embryo in vitro, 24 hours post-insemination (original magnification x33,810). A transversely cut sperm tail (arrowhead) is evident close to a protuberance of the paternal pronucleus (MPn). Mitochondria (M) have a dense stroma, and the vesicular smooth endoplasmic reticulum (S) is dilated.

PnM = pronuclear membrane

From: Sathananthan and Trounson, 1985. Reproduced with permission of the publisher, John Wiley & Sons.


Keywords: cytoplasmic organelles, paternal pronucleus, pronuclear membrane, sperm tail, stage 1b embryo, vesicular smooth endoplasmic reticulum


Source: The Virtual Human Embryo.