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Carnegie Stage   Figure

Partial phase of hatching

Partial phase of hatching

Low power light micrograph of a stage 3 embryo in vitro in the partial phase of hatching, post insemination day 6 (original magnification x400). The blastocyst has hatched halfway. Notice the flattened trophoblast (T) and the plump zona breaker cells (ZBC) at the hatching point.

BC = blastocystic cavity (blastocoele)
HP = hatching point
TV = trophoblast vesicle
ZP = zona pellucida

From: Sathananthan et al., 2003. Printed from Reproductive Biomedicine Online.


Keywords: blastocyst(s), blastocystic cavity (blastocoele), flattened trophoblast, hatching point, partial phase of hatching, trophoblast vesicle, zona breaker cells, zona pellucida


Source: The Virtual Human Embryo.