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Carnegie Stage   Figure

Early cavitation

Early cavitation

Early stage 3 embryo in vitro in early cavitation. Small fluid-filled areas are formed between cells. In time the fluid-filled areas will enlarge to form a single cavity named the blastocystic cavity (blastocoele). Decompaction has occurred resulting in blastomeres with distinct cell boundaries.Cells differ in size and shape but the inner cell mass (embryoblast) is not yet distinct.

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


Keywords: blastocystic cavity (blastocoele), blastomere, cavitation, elliptical trophoblast cell, inner cell mass (embryoblast), presumptive inner cell mass, subzonal space, zona pellucida


Source: The Virtual Human Embryo.