Physiology

Question 1

The placenta is what type of organ?

Answer 1

endocrine gland and transporting epithelium

Question 2

villi connected to the decidua basalis are called what? how are they connected?

Answer 2

anchoring villi connected by the cytotrophoblastic shell

Question 3

Which of the following during placentation accesses and erodes the spiral arteries?

1. syncytiotrophoblast
2. cytotrophoblast
3. chorion
4. anchoring villus
5. decidua basalis

Answer 3

cytotrophoblast

Question 4

Lacunae fuse to form what structure?

Answer 4

intervillious space

Question 5

Which hormones maintain and anchor the developing fetus to the uterus?

Answer 5

estrogen and progesterone

Question 6

What two layers separate maternal and fetal circulation?

Answer 6

syncytiotrophoblast and the endothelium

Question 7

Fetal Hgb has what subunits

Answer 7

alpha gamma which have a higher affinity for O2 (less avid binding of 2,3-BPG), than adult Hgb with the alpha and beta subunits

Question 8

What is the pO2 of umbilical venous blood and the pCO2 of umbilical arterial blood? What about O2 saturation in umbilical vein vs the umbilical arteries

Answer 8

pO2 30mmHg of venous
pC02 50mmHg vs 42 in the inter-villous space allowing for diffusion to the material blood

80-90% vein, then after entering the heart and mixing with blood from both the IVC (first) and SVC (RA) when it exits into the defending aorta and into the umbilical arteries it’s approx 50%

Question 9

What cell type is stimulated to proliferate and differentiate by IGF?

Answer 9

cytotrophoblasts

IGF insulin like growth factor