The Umbilical Cord Contains the Yolk Sac, the Placental Blood

Question

The umbilical cord contains the yolk sac, the placental blood vessels and the
A) chorionic villi.
B) allantois.
C) amnion.
D) chorion.
E) decidua.

Accepted Answer

The umbilical cord contains the allantois, which is a structure that is associated with embryonic development and becomes part of the urinary system in adults. The yolk sac and placental blood vessels are also present in the umbilical cord, but neither of these structures are listed as answer choices. The chorionic villi, amnion, and decidua are all structures that are associated with the placenta, but they are not directly present in the umbilical cord.