heart health
...or your body cells to function, and also carries waste products (such as carbon dioxide) back to the lungs for disposal. Blood is actually made up of four components, red blood cells, white blood cells, platelets and plasma. The blood vessels include arteries, capillaries and veins. Arteries have thick, muscular walls which carry the blood away from the heart at high pressure. The major artery of the body is the aorta. Capillaries are the smallest blood vessels. They have very thin walls through which nutrients are exchanged. The veins return blood back to the heart. Because the blood is not under much pressure at this stage, the walls of veins are not as muscular as those of arteries because the blood is under such low pressure, veins actually have valves which stop the blood running backwards. The aorta is the largest artery in the body, into which is pumped oxygenated Blood from from the side of the heart. The pulmonary arteries are found leaving the right side of the heart and carry deoxygenated blood to the lungs. as the blood moves further away form the heart, it travels through very small arteries called antroles arterioles branch into even smaller blood vessels called cappilleries. Cappilleries have se...