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Flashcards in Placenta- Shaw Deck (23)
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1
Q

What 2 cells types make up the trophoblast?

A

Cytotrophoblast

Syncytiotrophoblast

2
Q

Cytotrophoblast

A

Inner Layer of chorionic villi

Proliferate

3
Q

When do trophoblast cells become cytotrophoblast cells?

A

After attachment to the endometrium!

4
Q

In what phase of the uterine cycle does implantation occur?

A

During the secretory phase

5
Q

Describe Syncytiotrophoblast cells

A

Outer layer of chorionic villi
Don’t have boundaries
Multinucleated
Secrete hCG

**Lack MHCI expression to decrease chance of attack by maternal immune system

6
Q

Primary Villi

A

Trophoblast only (syncytiotrophoblast outside and cytotrophoblast inside)

**No extraembryonic mesoderm or blood vessels yet

7
Q

Secondary Villi

A

Mesodermal ingrowth into core of primary villus

Branching occurs

8
Q

Tertiary Villi

A

Differentiation of blood vessels in the mesodermal core of secondary villus

*Anastomosis of villar blood vessels with fetal circulation

9
Q

Describe an anchoring villus

A

Tertiary Villi
Cytotrophoblast has grown outside of syncytiotrophoblast to form a cytotrophoblastic shell

**Cytotrophoblast makes direct contact with decidual cells in endometrial stroma

10
Q

What is the decidual reaction?

A

Transformation of endometrial stromal cells

  • Swell due to glycogen and lipid accumulation
  • Transformation spreads through out superficial layers of endometrium
11
Q

What are the 3 placental components?

A

Decidua basalis
Decidua capsularis
Decidua parietalis

12
Q

What constitutes the maternal portion of the placenta?

A

Decidua basalis

*site of decidual reaction and most extensive villar invastion

13
Q

Decidua capsularis

A

Layer of placent between conceptus and uterine lumen

*becomes attenuated ast the embryo grows and eventually regresses

14
Q

Decidua parietalis

A

Remainder of endometrium not occupied by decidua basalis

15
Q

Cotyledons

A

Adjacent to decidua basalis

Placenta divided into 15-30 lobules by septae from decidua basalis

16
Q

How many tertiary villi are within a cotyledon?

A

2-4 and their branches

17
Q

What happens to the placental barrier as pregnancy progresses?

A

Gets thinner!

18
Q

What forms the cotyledons of the placenta?

A

Decidua Basalis

19
Q

TORCH Infections

A
Toxoplasmosis
other infections (Parvo B19)
Rubella
CMV
Herpes/HIV
e
Syphillis
20
Q

What placenta cells secrete hCG?

A

Syncytiotrophoblasts

*helps maintain corpus luteum and its production of progesterone and estrogen

21
Q

What do the synctiotrophoblasts secrete? 4 things…

A
  • hCG
  • Progesterone (at 12 wks)
  • Human placental lactogen
  • Converts androgens produced by fetal adrenal glands to estrogen
22
Q

What 3 things are produced by the decidua basalis?

A

Prolactin
Prostaglandins
Relaxin

23
Q

Relaxin is secreted by the decidua basalis… what does it do?

A

Softens pubic symphysis prior to parturition