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

Central cavity of a 4-cell embryo

Central cavity of a 4-cell embryo

TEM of the central cavity of a stage 2, 4-cell embryo in vitro, 44 hours post-insemination, (original magnification x8,510). Three blastomeres are shown in close contact with one another. The cavity contains cytoplasmic debris. Mitochondria (M) are very dense and form complexes with vesicles (V). The contents of the vesicular smooth endoplasmic reticulum (S) exhibit the same granularity as the vesicles.

From: Sathananthan, 1984. Reproduced with permission of the publisher, Elsevier.

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


Keywords: blastomere, central cavity, four-cell embryo, mitochondria, vesicular smooth endoplasmic reticulum


Source: The Virtual Human Embryo.