plastic surgery - An Overview
The zygote, which is the cell ensuing through the fertilization of the oocyte by a spermatozoon, is totipotent. A number of successive cell divisions generate the morula, with 32–64 totipotent cells. Following that stage, it develops into the blastocyst, which contains a hollow ball of cells. Peripheral cells (the trophoblast) on the blastocyst p