The reason much of the blood in the fetal right atrium is shunted to the left atrium through the foramen ovale is
A)the blood pressure in the right atrium is greater than in the left atrium.
B)there is a valve that directs the blood that way.
C)the fetus is in an antigravity situation provided by the amnionic fluid.
D)the blood pressure in the left atrium is greater than in the right atrium.
E)the umbilical arteries have valves.

Question

Quizplus · Accepted Answer

The blood pressure in the fetal right atrium is greater than in the left atrium, which is why much of the blood is shunted to the left atrium through the foramen ovale. This pressure difference facilitates the bypass of the pulmonary circulation, which is not needed for oxygen exchange in the fetus as it receives oxygenated blood through the placenta.

The Reason Much of the Blood in the Fetal Right