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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.

b) Sperm midpiece (arrow) is deep to the fertilization cone. The subzonal space is extensive. (original magnification x460).

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


Keywords: fertilization cone, second polar body, sperm midpiece, stage 1a embryo, subzonal space, telophase II


Source: The Virtual Human Embryo.