Course 2
Conception
Historical Notes
Beginning of Life?
No definite answer
Egg and Sperm
Coitus
Fertilization
Segmentation
Implantation
Multiple Pregnancies
Segmentation
懷孕

卵裂

卵裂:
通過細胞分裂,受精卵發育成桑葚胚,然後發育成囊胚。
Segmentation: 
The zygote, by cell division, grows into a morula an then into a blastocyst.

受精以後數小時內,也就是精子的細胞核與卵子的細胞核融合以後,所形成的這個受精卵開始內部的分裂過程。首先,它分裂成2個細胞,然後是4個、8個、16……等等,隨著每分裂一次,細胞數量加一倍。這種細胞的分裂或受精卵的分裂稱為卵裂。卵裂把受精卵轉換成稱為桑葚胚的細胞團,它在顯微鏡下看起來象桑葚果。桑葚胚慢慢地沿輸卵管向下、朝子宮移動,到達那裏約需3天。到這個時候,它已經發育成一個叫囊胚的中空細胞球了。
Conception

Segmentation

Within a few hours after fertilization, i.e. after the nucleus of the sperm has united with the nucleus of the egg, the result of their union, the zygote, begins a process of internal division. First, it divides into two cells, then four, eight, sixteen, and so on, doubling the number with each new division. This process of cell division or cleavage in the zygote is called segmentation. It transforms the zygote into a cluster of cells called morula which, seen through a microscope, resembles a mulberry. The morula slowly moves down the Fallopian tubes toward the uterus, where it arrives after about three days. By this time, it has developed into a hollow ball of cells called blastocyst.

[Course 2] [Description] [How to use it] [Introduction] [Conception] [Historical Notes] [Beginning of Life?] [No definite answer] [Egg and Sperm] [Coitus] [Fertilization] [Segmentation] [Implantation] [Multiple Pregnancies] [Pregnancy] [Birth] [Infertility] [Contraception] [Abortion] [Additional Reading] [Examination]