Fig. 7. TEM of the anaphase II spindle in a stage 1a embyro in vitro, 2 hours post-insemination (original magnification x11,130). The wide spindle shows sets of chromatin at each pole. The spindle microtubules end in the cytoplasm and dense material of the interbody (arrowhead) is forming at the spindle equator. The interbody determines the plane of cleavage of the second polar body. A few cortical granules (CG) are close to the surface of the embryo.
M, mitochondria; SS, subzonal space; S, resicular smooth endoplasmic reticulum; Z, zona pellucida.
(From: Sathananthan, 1985.Reproduced with permission of the publisher, John Wiley & Sons.)
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