DIFFERENCE BETWEEN ARTERIES, CAPILLARIES AND VEINS
external image Illu_capillary.jpg
Arteries
Capillaries
Veins
Away from heart
Wall only one cell thick-really thin -diffusion
Blood into heart
Mainly carry oxygenated blood
smallest blood vessel
Most carries de-oxygenated
High pressure

Lower pressure
No valves

Valves
Thick outer wall (pumps a lot more blood)

Thin outer walls
Thick inner layer of muscle and elastic fibres

Thin inner layer
Narrow central tube-small lumen(where the blood flows through)

Wide central tube -large lumen