General embryology : 2nd week of development

 2^nd week of development

For learning anatomy, please visit :

My youtube channel :  @easyhumanatomy73

My website : http://easyhumananatomy.com

My facebook page: https://www.facebook.com/easyhumanatomy/

My blog: http://www.easyhumanatomy73.blogspot.com

My blog: http://www.microscopicanatomybd.blogspot.com

It is known as the week of twos:

1.      The trophoblast differentiate into two layers

i) The cytotrophoblast                       

ii) The syncytotrophoblast

2. The embryoblast forms two layers

i) epiblast and

ii) hypoblast

3. two cavities form

i) amniotic and

ii) yolk sac

4. The extraembryonic mesoderm splits into two layers

i)somatopleuric mesoderm and

ii)splanchnopleuric mesoderm

5. Other features:

• uteroplacental circulation begin

• primary villi of placenta is formed
• chorionic cavity is formed