Multiple Choice
In placental mammals, the yolk sac
A) transfers nutrients from the yolk to the embryo.
B) differentiates into the placenta.
C) becomes a fluid-filled sac that surrounds and protects the embryo.
D) produces blood cells that then migrate into the embryo.
E) stores waste products from the embryo until the placenta develops.
Correct Answer:
Verified
Correct Answer:
Verified
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