Placental and Fetal Membranes (and Placental Hormones)

Question 1

Clinical Pregnancy dating ic calculated from ____________

Answer 1

first day of LMP

Question 2

1-week post-fertilizaiton is approximately ________ weeks from LMP in women with 28-day cycles

Answer 2

3 weeks from LMP

Question 3

8 weeks of gestation refers to how many completed weeks from LMP?

Answer 3

8 completed weeks

Question 4

What event/s occur on 0-2 Days of gestation?

Answer 4

Cleavage of the zygote

Question 5

What event/s occur on 3 Days of gestation?

Answer 5

Morula enters the uterine cavity

Question 6

What event/s occur on 4-5 Days of gestation?

Answer 6

58-cell blastula differentiates
Blastocyst is released from zona pellucida
Endometrial receptivity for hCG, Leukemia-inhibiting factor, CSF-1 (colony-stimulating factor)

Question 7

On Days 4-5 of gestation, the 58-cell blastula differentiates into:

Answer 7

5 embryo-producing cells
53 outer cells (trophoectoderm or outer layer) which forms the trophoblast

Question 8

At which Day/s of gestation does the blastocyst implants into the uterine wall?

Answer 8

Days 6-7

Question 9

What are the sequential events of uterine wall implantation?

Answer 9

Apposition
Adhesion
Invasion

Question 10

What are the hormones that prime the endometrium for the adhesion of the blastocyst and what structure produces them?

Answer 10

estrogen and progesterone from the corpus luteum

Question 11

Without priming of the endometrium, which compounds are synthesized preventing receptor interactions?

Answer 11

anti-adhesive glycoprotein

Question 12

When is the window of implantation?

Answer 12

Day 20-24

Question 13

This is one of the four families of CAMs and are cell surface receptors that mediate cell adhesion to extracellular matrix proteins

Answer 13

integrins

Question 14

Successful endometrial blastocyst adhesion at Days 6-7 involves modifed expression of which molecules?

Answer 14

cellular adhesion molecules (CAMs)

Question 15

These cells erodes the endothelial cell of the surface of the endometrium at Day 8 of gestation

Answer 15

trophoblasts

Question 16

Which primitive mononuclear cells differentiated from trophoblasts form the inner layer as the blastocyt invades deeply into the endometrium?

Answer 16

Cytotrophoblasts

Question 17

At which day of gestation do the trophoblasts differentiate into the inner and outer layers of cells?

Answer 17

Day 8

Question 18

These are multinucleated primitive syncytium of trophoblastic cells that forms the outer layer on the 8th Day

Answer 18

Syncytiotrophoblasts

Question 19

After invasion (implantation) of the blastocyst, the trophoblasts further differentiate into 2 pathways which are:

Answer 19

villous trophoblasts and extravillous trophoblasts

Question 20

What are the 2 differentiations of extravillous trophoblasts?

Answer 20

interstitial and endovascular trophoblasts

Question 21

These are the extravillous trophoblasts responsible in converting the spiral arteries into low resistance, highly pliable, and straightened out vessels

Answer 21

Endovascular trophoblasts

Question 22

At which day of gestation us the blastocyst completely buried or encased and covered by maternal endometrium?

Answer 22

Day 10

Question 23

These are primitive blood circulation formed during the 10th to 12th day of gestation

Answer 23

Lacunae network

Question 24

Which of the following is true at the 12th day of gestation?
A. Secondary and Tertiary villi are already formed
B. There is already mixing of blood from the maternal and embryonic side, which is important for the survival of the fetus
C. The cotyledon is completely formed formed
D. Fetal-placental circulation completed with the blood vessels of the embryo are connected with the chorionic vessels
E. Chorion frondosum towards the endometrial cavity lose its blood supply and villous nature

Answer 24

B. There is already mixing of blood from the maternal and embryonic side, which is important for the survival of the fetus

A - Day 14
C - Day 40-50
D - Day 17
E - Day 40-50

Question 25

Primary villi arise from buds of cytotrophoblasts that
protrude into the primary syncytium at Days
A. Day 10-11
B. Day 13-14
C. Day 15-17
D. Day 19-21

Answer 25

A. Day 10-11

Question 26

Which cells of the placenta is permeated by the system of intercommunicating channels (trophoblastic lacunae) during the 12th Day of gestation?

Answer 26

Syncytiotrophoblasts

Question 27

Decidual stromal cell enlargements and increase in glycogen storage occurs in day:

Answer 27

12

Question 28

During early pregnancy, a space lies between the decidua capsularis and parietalis because the gestational sac does not fill the entire uterine cavity. The gestational sac is the ______________ and also called the chorionic cavity.

Answer 28

extraembryonic coelom

Question 29

At day 13 onwards, formation of connecting stalk occurs, this structure is also known as the:

Answer 29

primitive umbilical cord

Question 30

When are the secondary and tertiary villi formed?

Answer 30

Day 14

Primary is at Day 10 to 11

Question 31

Tertiary villi are only formed once ______ begins in the mesenchymal cords

Answer 31

angiogenesis