Lecture 36: Placenta and Fetal Membranes

Question 1

Where is the fetal part of the placenta derived from?

Answer 1

Chorionic sac

Question 2

Where is the maternal part of the placenta derived from?

Answer 2

Endometrium

Question 3

What is the decidua?

Answer 3

Functional layer of endometrium that separates from uterus after childbirth
-contributes to maternal placenta

Question 4

What are the layers of decidua?

Answer 4

Decidua basalis: deep layer that forms maternal part of placenta
Decidua capsularis: Superficial layer
Decidua parietalis

Question 5

What do trophoblasts differentiate into?

Answer 5

1) Cytotrophoblasts: inner layer

2) Syncytiotrophoblast: invades and displaces decidual cells of endometrium

Question 6

Where does lacunae appear?

Answer 6

Syncytiotrophoblast layer

-fill with blood and uterine secretions

Question 7

What is the primordial uteroplacental circulation?

Answer 7

Oxygen and nutrients passing via diffusion through lacunar networks