Stage 10 (6 hrs 30 min)
Early blastula stage
Drown by T. Iwamatsu
(Abbr. mc: marginal cell, pn: nucleus of periblast)
Stage 10 (6 hrs 30 min) Early blastula stage:
The blastoderm (about 1,000 cells) is still high (thick) as in the late morula stage, although its inner cells (20-30 um in diameter) are smaller. According to Kageyama [19], the11th cleavage still takes place synchronously. Nuclei from the marginal cells (40, cf.[19]) migrate out of the cells and are distributed in a few rows in the periblast (cortical syncytial layer).