Skip Navigation
Stage 1 / 1 day Stage 2 / 2-3 days Stage 3-1 / 4 days Stage 3-2 / 4-5 days Stage 4 / 6 days Stage 5a-1 / 7 days Stage 5a-2 / 8 days Stage 5b / 9 days Stage 5c / 12 days Stage 6 / 13-17 days Stage 7 / 16-19 days Stage 8 / 23 days Stage 9 / 25 days Stage 10 / 28 days Stage 11 / 29 days Stage 12 / 30 days Stage 13 / 32 days Stage 14 / 33 days Stage 15 / 36 days Stage 16 / 39 days Stage 17 / 41 days Stage 18 / 44 days Stage 19 / 45-47 days Stage 20 / 49 days Stage 21 / 49-52 days Stage 22 / 52-55 days Stage 23 / 56 days
Carnegie Stage   Figure

The cortical area next to the fertilization cone

The cortical area next to the fertilization cone

Very high power TEM of the cortical area next to the fertilization cone of a stage 1a embryo in vitro, three hours after insemination (original magnification x27,300). Notice some of the released products are still attached to the cell membrane of the embryo (arrowheads).

SS = subzonal space

From: Sathananthan and Trounson, 1982. Reproduced with permission of the publisher, John Wiley & Sons.

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


Keywords: cell membrane of the embryo, fertilization cone, stage 1a embryo, subzonal space


Source: The Virtual Human Embryo.