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Carnegie Stage   Figure

Undifferentiated cell mass

Undifferentiated cell mass

The undifferentiated cell mass increases in size in the next few sections and is inseparable from the ectoderm and endoderm. A cloacal membrane is not yet present, but it will presumably develop in this place. Section 154.

Fig. 9. Heuser et al., 1945.


Keywords: cloacal membrane, ectoderm, endoderm


Source: The Virtual Human Embryo.