Capillaries

The capillaries are the smallest blood vessels in our circulatory system, linking the arterial and venous sides. The capillaries are where the important deliveries and pick-ups occur. They are a single cell in diameter and this helps the easy transfer of gases and nutrients. Capillaries deliver vital nutrients and oxygen to the tissues of the body and at the same time collect waste products and carry them to various locations of the body. There are important capillaries in the lungs which pick up oxygen from the air that has been inhaled, exchanging it for carbon dioxide to be exhaled; and in the kidneys wastes are transferred from capillaries into the urine. In the intestines, capillaries pick up nutrients and also release wastes. Sometimes capillaries under the skin of the face or lower legs can become dilated and visible.