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Carnegie Stage   Figure

Second polar body in the subzonal space

Second polar body in the subzonal space

Stage 1a embryo penetrated oocyte in vitro. The second polar body is in the subzonal space indicating sperm penetration of the cell membrane. Pronuclei are absent.

From: Jirásek, 2001. Reproduced with permission of the publisher, Taylor & Francis Group.

Click on the picture to view the full-sized image.


Keywords: cell membrane, penetrated oocyte, pronucleus, second polar body, sperm penetration, stage 1a embryo, subzonal space


Source: The Virtual Human Embryo.