A pregnant woman comes to her physician with questions about effect that ingested substances may have on her unborn child. The physician explains that large molecules do not pass between the mother and fetus because of the placental barrier. The physician adds that fetal blood is the fetal blood vessels of the villi of the placenta and the mother's blood is in the maternal blood vessels, and that these blood vessels do not connect. The placental villa are formed from which of the following cells?

A pregnant woman comes to her physician with questions about effect that ingested substances may have on her unborn child. The physician explains that large molecules do not pass between the mother and fetus because of the placental barrier. The physician adds that fetal blood is the fetal blood vessels of the villi of the placenta and the mother's blood is in the maternal blood vessels, and that these blood vessels do not connect. The placental villa are formed from which of the following cells?

A pregnant woman comes to her physician with questions about effect that ingested substances may have on her unborn child. The physician explains that large molecules do not pass between the mother and fetus because of the placental barrier. The physician adds that fetal blood is the fetal blood vessels of the villi of the placenta and the mother's blood is in the maternal blood vessels, and that these blood vessels do not connect. The placental villi are formed from which of the following cells?



(A)Cytotrophoblast
(B)Embryoblast
(C)Endometrium
(D)Epiblast
(E)Syncytiotrophoblast

Answer: E: Syncytiotrophoblast