1. What is the primary function of the placenta in humans?
a) Producing hormones
b) Transporting nutrients
c) Exchanging gases
d) All of the above
Answer: d) All of the above
2. Which structure forms the fetal portion of the placenta?
a) Amniotic sac
b) Chorion
c) Umbilical cord
d) Placental villi
Answer: b) Chorion
3. The placenta is connected to the fetus via the:
a) Uterine wall
b) Placental villi
c) Umbilical cord
d) Amniotic fluid
Answer: c) Umbilical cord
4. The placental barrier prevents the exchange of which of the following?
a) Nutrients
b) Oxygen
c) Large molecules and microorganisms
d) Waste products
Answer: c) Large molecules and microorganisms
5. The placenta secretes which of the following hormones?
a) Progesterone
b) Estrogen
c) Human chorionic gonadotropin (hCG)
d) All of the above
Answer: d) All of the above
6. Which of the following is true about the placental blood supply?
a) The fetal blood is separated from maternal blood
b) The maternal and fetal blood mix freely
c) The maternal blood circulates directly in the fetus
d) The fetus has its own circulatory system independent of the placenta
Answer: a) The fetal blood is separated from maternal blood
7. The placenta develops from the:
a) Embryo
b) Ovary
c) Endometrium of the uterus
d) Uterine lining
Answer: c) Endometrium of the uterus
8. Which layer of the placenta is responsible for nutrient and gas exchange?
a) Trophoblast
b) Cytotrophoblast
c) Syncytiotrophoblast
d) Amnion
Answer: c) Syncytiotrophoblast
9. Which of the following is NOT a function of the placenta?
a) Gas exchange
b) Hormonal secretion
c) Protein synthesis
d) Immune protection
Answer: c) Protein synthesis
10. The umbilical cord contains which of the following vessels?
a) Two veins and one artery
b) One vein and two arteries
c) One vein and one artery
d) Two arteries and two veins
Answer: b) One vein and two arteries
11. The primary role of the placenta is to:
a) Provide mechanical support to the fetus
b) Exchange nutrients and waste between mother and fetus
c) Protect the fetus from toxins
d) Produce antibodies for the fetus
Answer: b) Exchange nutrients and waste between mother and fetus
12. The maternal side of the placenta is primarily composed of:
a) Syncytiotrophoblasts
b) Decidua basalis
c) Amniotic fluid
d) Umbilical vessels
Answer: b) Decidua basalis
13. Which hormone is responsible for maintaining pregnancy by preventing menstruation?
a) Progesterone
b) Estrogen
c) hCG
d) Oxytocin
Answer: a) Progesterone
14. What is the role of the umbilical vein?
a) Carries oxygenated blood to the fetus
b) Carries deoxygenated blood to the placenta
c) Transports hormones
d) Stores nutrients
Answer: a) Carries oxygenated blood to the fetus
15. Which of the following hormones is produced by the placenta to prevent immune rejection of the fetus?
a) hCG
b) Progesterone
c) Human placental lactogen (hPL)
d) Estrogen
Answer: c) Human placental lactogen (hPL)
16. The exchange of gases in the placenta primarily occurs by:
a) Active transport
b) Endocytosis
c) Diffusion
d) Osmosis
Answer: c) Diffusion
17. The placenta provides immunological protection by:
a) Producing antibodies
b) Providing a barrier to pathogens
c) Producing white blood cells
d) Neutralizing toxins
Answer: b) Providing a barrier to pathogens
18. The placenta reaches its maximum size at approximately:
a) 10 weeks
b) 20 weeks
c) 30 weeks
d) 40 weeks
Answer: c) 30 weeks
19. Which of the following is true about the exchange of waste products in the placenta?
a) Waste products are excreted by the placenta into maternal blood
b) Waste products remain in the fetal circulation
c) Waste products are excreted directly through the umbilical cord
d) Waste products are stored in the amniotic fluid
Answer: a) Waste products are excreted by the placenta into maternal blood
20. What happens if the placenta is not functioning properly?
a) The fetus will grow normally
b) Fetal development may be impaired
c) The fetus will receive excess oxygen
d) The mother will experience increased hormone levels
Answer: b) Fetal development may be impaired
21. Which structure in the placenta is responsible for absorbing nutrients?
a) Placental villi
b) Umbilical cord
c) Amniotic sac
d) Cytotrophoblast
Answer: a) Placental villi
22. Which hormone secreted by the placenta helps in the development of the mammary glands for lactation?
a) Progesterone
b) Estrogen
c) hCG
d) Human placental lactogen
Answer: d) Human placental lactogen
23. During pregnancy, the placenta acts as:
a) A filter to remove excess nutrients
b) An endocrine organ
c) A respiratory organ
d) All of the above
Answer: d) All of the above
24. The process of blood circulation through the placenta is called:
a) Transplacental circulation
b) Placental perfusion
c) Fetal-placental circulation
d) Maternal blood circulation
Answer: c) Fetal-placental circulation
25. Which of the following substances does NOT pass freely through the placental barrier?
a) Oxygen
b) Carbon dioxide
c) Glucose
d) Large proteins
Answer: d) Large proteins
26. The placenta is typically expelled from the mother’s body during:
a) The first trimester
b) The second trimester
c) The third trimester
d) Labor
Answer: d) Labor
27. The fetal blood in the placenta is in direct contact with which part of the maternal tissue?
a) Endometrium
b) Decidua basalis
c) Myometrium
d) Uterine cervix
Answer: b) Decidua basalis
28. The placenta contributes to the process of parturition by secreting which hormone?
a) Estrogen
b) Progesterone
c) Oxytocin
d) hCG
Answer: c) Oxytocin
29. Which of the following is a characteristic feature of the placental villi?
a) They are involved in nutrient absorption
b) They secrete hormones
c) They provide mechanical protection to the fetus
d) They are involved in amniotic fluid production
Answer: a) They are involved in nutrient absorption
30. How does the placenta prevent the rejection of the fetus by the maternal immune system?
a) By producing immunosuppressive hormones
b) By releasing antibodies
c) By reducing maternal immune response
d) By isolating fetal cells from maternal circulation
Answer: a) By producing immunosuppressive hormones
