Bilaminar Embryo

Question 1

Decidual reaction

Answer 1

A reorganizing of the uterine stroma to accomodate the possibility of a fertilized embryo attaching

Question 2

What are the two layers of the inner cell mass?

Answer 2

Epiblast and hypoblast

Question 3

What fetal structure secretes what hormone around the time of implantation to maintain pregnancy?

Answer 3

The synctiotrophoblast secretes hCG to maintain pregnancy

Question 4

What is the Chorion comprised of and what does it do?

Answer 4

Comprised of 1) Somatic layer of extraembryonic mesoderm, 2) Cytotrophoblast, 3) Synctiotrophoblast. It contributes to the fetal portion of the placenta

Question 5

What is molar pregnancy?

Answer 5

Massive proliferation of trophoblastic cells, but no fetal tissue (egg was empty)

Question 6

Give the five tenets of the rule of two

Answer 6

1) Applies to second week, 2) Trophoblast has two layers, 3) Blastocyst cavity forms twice, 3) Two unique cavities are formed, 4) Two populations of extraembryonic mesoderm arise (somatic and splanchnic), 5) Embryonic disc is bilaminar