The purpose of the foramen ovale and the ductus arteriosus is to permit most blood to:
A)bypass the fetal liver
B)flow more slowly through the fetal lungs
C)flow through the fetal liver
D)bypass the fetal lungs

Question

Quizplus · Accepted Answer

The foramen ovale and the ductus arteriosus are two important structures developed during fetal life that allow most of the blood to bypass the lungs, which are not functional until birth. The foramen ovale is a hole between the right and left atria of the fetal heart that allows oxygenated blood to enter the left atrium and then the left ventricle without passing through the lungs. The ductus arteriosus is a shunt between the pulmonary trunk and the aorta that allows most of the blood from the right ventricle to go directly to the aorta, bypassing the non-functional fetal lungs. Together, these structures allow the fetus to receive oxygenated blood from the placenta without having to rely on its own lungs for oxygenation, which only occurs after birth.

The Purpose of the Foramen Ovale and the Ductus Arteriosus