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Carnegie Stage   Figure

Expansion and contraction

Expansion and contraction

Stage 3 embryos in vitro showing expansion. On the left is a smaller embryo in early cavitation with a thick zona pellucida. On the right is an expanded embryo with enlargement of the blastocystic cavity (blastocoele) and a thin zona pellucida.

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


Keywords: abembryonic pole, early cavitation, embryonic pole, inner cell mass (embryoblast), polar trophoblast, thick zona pellucida, thin zona pellucida


Source: The Virtual Human Embryo.