Describe the structural differences between arteries, veins and capillaries and link to their function

Arteries - Small lumen, large amount of smooth muscleSmall lumen provides increased blood pressure for blood to flow all across body - smooth muscle provides necessary force to push blood across body
Veins - Large lumen, contain valvesLarge lumen allows high volume of blood to return to heart, valves help to prevent backflow
Capillaries - 1 endothelial cell thickThinness of capillaries allow for short diffusion distance of substances to and from surrounding tissue