The explanation for this must lie in the biochemical maturity of eight-celled embryos compared with their junior, four-cell siblings.
对于这一现象只能解释为，在生化意义上发育至八个细胞的胚胎比只有4个细胞的初级胚胎要成熟。
2
There are risks involved with preimplantation testing, which generally involves removal of one or more cells from an eight-cell embryo called a blastocyst.
着床前检查一般要从一个称为胚泡的8细胞胚胎中取出1个或更多细胞，该过程也存在一定风险。
3
If the spiral of the shell is changed at the eight-cell stage then the orientation of the snail's heart, stomach, liver coiling and gut looping are similarly flipped.