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Carnegie Stage   Figure

High power LM of section through the fertilization cone

High power LM of section through the fertilization cone

A series of six high power LMs of sections through a stage 1a embryo in vitro showing telophase II of the second polar body, 3 hours post-insemination.

d) The expanding nuclear chromatin of the sperm (red arrow) is visible deep to the fertilization cone (blue arrow) (original magnification x460). A dense band of microfilaments are evident deep to the fertilization cone. Sperm heads are present in the zona pellucida.

From: Lopata et al., 1980. Reproduced with permission of the American Society for Reproductive Medicine.


Keywords: chromatin, fertilization cone, microfilament(s), second polar body, sperm head, telophase II, zona pellucida


Source: The Virtual Human Embryo.