Difference in structure of arteries and veins and how this relates to their function

Blood vessels allow blood to be circulated around the whole body for delivery of oxygen/nutrients and removal of waste products. The structure of arteries and veins helps them to perform their specific functions. • Arteries - take oxygenated blood away from the heart. Arteries have thick, muscular, elastic walls with small lumens, which means they can both withstand and maintain the high pressure of blood being pumped from the heart. This allows blood to be carried all around the body. • Veins - return deoxygenated blood back to the heart. Unlike arteries, veins only need to withstand a low pressure as they carry blood back to the heart. This means they have thin walls, with large lumens. They also contain valves, which shut after each contraction of the heart, to prevent backflow of blood. The varying structures of these blood vessels are key to helping them perform their function of circulating blood – and therefore delivering nutrients and removing waste - to cells around the body.