There's one division, here it shows it at the 16 cell stage and then here, and this transformation as it goes from 16 cells to more like 64 cells.

这是第一次分裂,这里显示的是十六细胞期,然后在这里,在这里胚胎进一步的产生了变化,由十六个细胞分裂为约六十四个

耶鲁公开课 - 生物医学工程探索课程节选