Anatomy and Physiology II Practice Test

The pulmonary veins primarily carry oxygenated blood from the lungs to the heart. After blood picks up oxygen in the alveoli of the lungs, it enters the pulmonary circulation, where it travels through the pulmonary veins. These veins transport the freshly oxygenated blood directly into the left atrium of the heart. This oxygen-rich blood is then pumped into the left ventricle and distributed throughout the body via the aorta. This pathway is crucial as it ensures that tissues receive an adequate supply of oxygen necessary for cellular respiration and energy production. Hence, the primary role of the pulmonary veins in the circulatory system is to deliver oxygenated blood to the heart, making oxygenated blood the correct and primary answer for this question.