blood a pump (the heart) to push the blood around the body a system of tubes to contain the blood (arteries, veins and capillaries) The blood is the transport medium – it carries substances to ...

All blood vessels are specifically structured to perform their function. For example, a capillary is microscopically thin to allow gases to exchange, the arteries are tough and flexible to cope ...

The heart is a muscle about the size of your fist. Your heart pumps blood and oxygen to all of the organs and tissues of the body through a network of “pipes” called arteries and veins. The heart ...