Which type of blood vessels are responsible for returning blood to the heart?

Veins are the type of blood vessels responsible for returning blood to the heart. They collect deoxygenated blood from the body and transport it back towards the heart, where it can then be directed to the lungs for oxygenation.

The structure of veins is key to their function: they have valves that prevent the backflow of blood and a thinner muscular wall compared to arteries, which allows them to accommodate varying amounts of blood volume. As blood moves through the venous system, it is assisted by the contraction of surrounding skeletal muscles and pressure changes during breathing, which help push the blood back toward the heart.

In contrast, arteries carry oxygenated blood away from the heart to the rest of the body, capillaries serve as the sites of gas and nutrient exchange between blood and tissues, and the aorta is the largest artery in the body that originates from the heart, primarily responsible for distributing oxygenated blood to the systemic circulation.