The extraembryonic membrane that forms a fluid-filled sac is the
A) yolk sac.
B) amnion.
C) allantois.
D) all of the above
E) none of the above

Question

Quizplus · Accepted Answer

The amnion is the extraembryonic membrane that forms a fluid-filled sac, known as the amniotic sac, which surrounds and protects the embryo. The yolk sac and allantois are also extraembryonic membranes, but they do not form fluid-filled sacs.

The Extraembryonic Membrane That Forms a Fluid-Filled Sac Is the