Which fetal structure shunts blood from the right atrium to the left atrium?

Prepare for the Anatomy and Physiology II Exam with comprehensive questions and detailed explanations. Gain confidence with our tailored quizzes and maximize your exam performance!

Multiple Choice

Which fetal structure shunts blood from the right atrium to the left atrium?

In fetal circulation, shunts redirect blood away from the nonfunctional lungs. The opening between the right and left atria—the foramen ovale—lets blood move directly from the right atrium to the left atrium, sending highly oxygenated blood from the placenta into the systemic circulation without going through the lungs. After birth, increased left atrial pressure closes this opening, forming the fossa ovalis. The other vessels have different roles: the ductus arteriosus routes blood from the pulmonary artery to the aorta, while the umbilical vein brings oxygenated blood from the placenta to the fetus and the umbilical arteries carry blood back to the placenta.

In fetal circulation, shunts redirect blood away from the nonfunctional lungs. The opening between the right and left atria—the foramen ovale—lets blood move directly from the right atrium to the left atrium, sending highly oxygenated blood from the placenta into the systemic circulation without going through the lungs. After birth, increased left atrial pressure closes this opening, forming the fossa ovalis. The other vessels have different roles: the ductus arteriosus routes blood from the pulmonary artery to the aorta, while the umbilical vein brings oxygenated blood from the placenta to the fetus and the umbilical arteries carry blood back to the placenta.

More practice questions