Monthly Archives: January 2007
blastocyst | Blastozyste | 胚泡
| January 8, 2007 | Posted by 武卓敏 under 术语百汇-生物科技 |
↓↓↓↓↓↓↓↓↓↓英文解释↓↓↓↓↓↓↓↓↓↓
The blastocyst is an early stage of the human (or other mammal) development early in pregnancy. It is the structure formed in early human embryogenesis, after the formation of the blastocoel, but before implantation. It possesses an inner cell mass, or embryoblast, and an outer cell mass, or trophoblast. The human blastocyst comprises 70-100 cells. It is preceded by a zygote, the fertilized egg cell, and succeeded by an embryo. Other definitions consider the blastocyst an intermediate stage of the embryo, and begin using the term blastocyst at day 5 (16-20 cells.)[1] (more…)
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