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Carnegie Stage   Figure

Interpronuclear zone

Interpronuclear zone

Very high power TEM of the interpronuclear zone in a stage 1b embryo in vitro, 17 hours post-insemination (original magnification x33,810). The narrow region of cytoplasm contains mitochondria (M) associated with smaller elements of the smooth endoplasmic reticulum. The mitochondria have dense stromae and few cristae.

PnM = pronuclear membrane
Pn = pronucleus

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


Keywords: cristae, interpronuclear zone, mitochondria, smooth endoplasmic reticulum, stroma(e)


Source: The Virtual Human Embryo.