Arteries, Veins and Capillaries Biology Study Material
- The next major components of the cardiovascular system are the blood vessels. These are a network of tubes that transport the blood around the body. There are three types of blood vessels which all carry out different functions:
- Arteries carry blood away from the heart and veins carry blood back to the heart. When an artery reaches an organ it branches out into capillaries. It is in the capillaries where substances such as oxygen, food and carbon dioxide are exchanged between the blood and organ cells. The capillaries then join up to form veins. Capillaries are the links between arteries and veins
- Arteries carry blood away from the heart. They carry rich oxygenated blood towards the body. This blood is under high pressure as it is being pumped along by the heart every time it beats. In order for arteries to withstand this pressure they have special design features. Arteries have thick muscular walls which contain elastic fibres that allow the artery to stretch under pressure. The muscle fibres also contract to push the blood along and keep it flowing. In addition the narrow lumen maintains a high pressure and ensures the blood flows quickly to all parts of the body. The contracting of the arteries can be felt in your body as a pulse, for example at your wrist or neck.