blood vessels

• the three blood vessels are the artery , vein and capillary
• ateries carry blood at a high pressure away from the heart
• arterys have thick and muscular walls, small lumen
• veins carry blood at a low pressure towards the heart
• veins have thin walls and a large lumen to allow blood to flow quickly, also have valves to maintain blood flow
• capillarys exchange gases and nutrients with the blood and remove waste products
• capillaries are one cell thick, large surface area, permeable wall and a small lumen