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Carnegie Stage   Figure

Close up view of polarized pronuclei

Close up view of polarized pronuclei

LM of a close up view of polarized pronuclei in a stage 1b embryo in vitro. The pronuclei have aligned perpendicular to the second polar body axis (double-headed arrow). This is the correct position for syngamy and the first cleavage.

From: Veeck and Zaninovic´, 2003. Reproduced with permission of the publisher, Taylor & Francis Group.


Keywords: first cleavage, polarized pronuclei, pronucleus, second polar body, stage 1b embryo, syngamy


Source: The Virtual Human Embryo.