Most _______ have valves that permit the flow of blood toward the heart, even against the force of gravity.

Question

Quizplus · Accepted Answer

Veins have one-way valves that allow blood to flow toward the heart and prevent backflow. This is important for returning blood to the heart, especially in the lower extremities, where blood must flow against gravity to reach the heart. Arteries and capillaries do not have valves, and sinuses are open spaces in tissues rather than blood vessels.

Most _______ Have Valves That Permit the Flow of Blood