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Carnegie Stage   Figure

First cleavage nearing completion

First cleavage nearing completion

LM of a late stage 1c embryo in vitro, 24 hours after intracytoplasmic sperm injection (ICSI). Cell membranes have not yet completely separated the zygote into two cells. Nucleus is forming as embryo is dividing into two blastomeres.

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


Keywords: blastomere, first cleavage, nucleus, stage 1c embryo, zygote


Source: The Virtual Human Embryo.