Physiology of Pregnancy and the Fetus

Question 1

Explain how the main functions of the placenta make it essentially the fetal gut, lung, kidney, and endocrine gland

Answer 1

gut: supply nutrients
lung: exhcnage O2 and CO2
kidnye: regulate fluid volume and get rid of waste

endocrine gland: synthesize steroids and proteins that affect metabolism of mother and fetus

Question 2

OF the 3 major features of the placent, which on is the functional unit? Bonus: why?

A. Chorionic villi

B. Intervillous space

C. Decidua basalis

Answer 2

Chorionic villi

• extensive branching that increases the amount of surface area for exchange

Question 3

REgulation of blood flow in the placenta involves maternal and fetal aspects. Which portion involves the use of capillaries?

A, Maternal

B. Fetal

Answer 3

Fetal

• the umbilical aa. branch and form a capillary network to obtain O2 and nutrients that get’s returned bia umbilical V.
• maternal portion has no capillaries

Question 4

What features exist in maternal portion that help reduce the velocity of blood flow to allow greater nutrient exchange?

What features exist in fetal portion that help reduce the velocity of blood flow to allow greater nutrient exchange?

Answer 4

Maternal

• spiral arteries filling large intervillous space

Fetal

• dilations at the terminal ends of capillary network

Question 5

PO2 drops from maternal side to fetal side, which should result in lower O2 saturation of fetal hemoglobin. However, we see high O2 saturation of fetal Hb, why is this?

Answer 5

Fetal Hb structure allows for sufficient Hb saturation (higher affinity)

Question 6

What factors favor CO2 transfer from fetus to mother? (2)

Answer 6

Higher [CO2] at umbilical aa. than in intervillous space

Fetal blood has a lower affinity for CO2 than maternal blood

Question 7

How does non-protein nitrogen waste like urea/creatine or lipid soluble hormones get transfered between mother and fetus?

A. Facilitated diffusion

B. Primary and SEcondary active transport

C. Passive exchange

D. Receptor mediated endocytosis

Answer 7

Passive exchange

Question 8

How does glucose get transfered between mother and fetus?

A. Facilitated diffusion

B. Primary and SEcondary active transport

C. Passive exchange

D. Receptor mediated endocytosis

Answer 8

Facilitated diffusion

Question 9

How do amino acids, vitamins, and minerals get transfered between mother and fetus?

A. Facilitated diffusion

B. Primary and SEcondary active transport

C. Passive exchange

D. Receptor mediated endocytosis

Answer 9

Primary and SEcondary active transport

Question 10

How do LDLs, hormones like insulin, and Abs (igG) get transfered between mother and fetus?

A. Facilitated diffusion

B. Primary and SEcondary active transport

C. Passive exchange

D. Receptor mediated endocytosis

Answer 10

Receptor mediated endocytosis

• Large molecule exchange utilizes receptor mediated endocytosis

Question 11

T/F: Mother provides cholesterol and fetal adrenal gland and liver supply the enzymes the placenta lacks

Answer 11

True

Question 12

What are the signs and symptoms that characterize preeclampsia?

Some serious and fatal complications that occur if preeclampsia is left untreated are eclampsia and HELLP. What does HELLP stand for?

Answer 12

High blood pressure, kidney damage, proteinuria, generalized edema

HELLP

Hemolysis, Elevated Liver enzymes, Low Platelet count

Question 13

T/F: Preeclampsia is associated with limited blood supply to the uterine arteries that cause ischemia and endothelial damage that triggers release of cytokines

Answer 13

True

Question 14

In order of earliest to latest, what structures contribute to blood cell formation in the fetus?

A. bone marrow > liver > yolk sac

B. yolk sac> bone marrow > liver

C. yolk sac > liver > bone marrow

D. liver > yolk sac > bone marrow

Answer 14

yolk sac > liver > bone marrow