Which vessel carries deoxygenated blood from the heart to the lungs for gas exchange?

• A. Pulmonary Trunk
• B. Left Subclavian Artery
• C. Superior Vena Cava
• D. Descending Aorta

Answer: (A)

During pulmonary circulation, deoxygenated blood leaves the heart to go to the lungs through a vessel that originates from the right ventricle. This vessel is the pulmonary trunk, which soon divides into the right and left pulmonary arteries to carry blood to the lungs for gas exchange. After the blood is oxygenated, it returns to the heart via the pulmonary veins into the left atrium.

The left subclavian artery is part of the systemic circulation and delivers oxygen-rich blood to the left arm. The superior vena cava brings deoxygenated blood from the head, neck, and upper limbs back to the right atrium. The descending aorta distributes oxygenated blood to the rest of the body. Thus, the pulmonary trunk is the vessel that carries deoxygenated blood from the heart to the lungs for gas exchange.