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Carnegie Stage   Figure

Polar trophoblast

Polar trophoblast

TEM of the polar trophoblast of a mid blastocyst, stage 3 embryo, 96-120 hours post-insemination (original magnification x3,100). Arrowheads indicate apical tight junction regions.

SL = secondary lysosome-like bodies
V = vacuole
ZP = zona pellucida

Left inset: Enlargement of an apical tight junction region (original magnification x12,800).

Right inset: Thick section of the mid blastocyst showing the inner cell mass (embryoblast) and the blastocystic cavity (blastocoele) (original magnification x440).

From: Gualtieri et al., 1992. Reproduced with permission of the publisher, John Wiley & Sons.

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


Keywords: apical tight junction, blastocyst(s), inner cell mass (embryoblast), polar trophoblast, secondary lysosome-like bodies, vacuole(s), zona pellucida


Source: The Virtual Human Embryo.