How do veins differ from arteries in terms of blood flow?

Veins differ from arteries primarily in their function related to blood flow. While arteries carry blood away from the heart, typically under higher pressure and with thicker walls due to the muscular structure that helps pump blood through the circulatory system, veins have a different role. Veins are responsible for returning blood to the heart.

The statement regarding veins typically exhibiting a "flow" of blood captures the essence of how veins operate in the circulatory system. Blood flow in veins is often facilitated by the presence of one-way valves, which prevent backflow and assist in the movement of blood, especially in areas that are further away from the heart and against gravity, such as in the legs. The context of blood flow in the veins highlights the importance of their structure and function in the overall circulatory process, which differs from the higher-pressure system of arteries.

This understanding of venous blood flow contrasts with the other options, as they do not accurately characterise the primary differences between veins and arteries. For instance, arteries are the ones that carry oxygenated blood (with some exceptions, such as the pulmonary arteries) and lead away from the heart, while veins carry deoxygenated blood (again, with some exceptions, such as pulmonary veins). Additionally, veins