Blood returning from the lungs to the heart travels via which vessels?

• A. Pulmonary veins
• B. Pulmonary arteries
• C. Aorta
• D. Superior vena cava

Answer: (A)

When blood finishes gas exchange in the lungs, it is oxygen-rich and needs to move into the heart’s left side to be pumped out to the body. It does so through the pulmonary veins, which drain the lungs and empty into the left atrium. This pathway is what distinguishes the pulmonary veins from other vessels: they return blood to the heart, and they do so specifically into the left atrium to then enter the left ventricle and systemic circulation.

The pulmonary arteries carry blood from the right ventricle to the lungs; the aorta carries oxygen-rich blood from the left ventricle to the body; the superior vena cava brings deoxygenated blood from the upper body to the right atrium. So the vessels that return blood from the lungs to the heart are the pulmonary veins.