Arteries
Arteries carry blood at high pressure (80 - 120 mm Hg)
They have a narrower lumen (to maintain high pressure) surround by a thick wall made of two layers
The middle layer (tunica media) contains muscle and elastin to help maintain pulse flow (it can contract and stretch)
The outer layer (tunica adventitia) contains collagen prevents the artery rupturing due to the high pressure blood flow
Veins
Veins carry blood under low pressure (<10 mm Hg)
They have a very wide lumen (keeps pressure low and allows greater flow of blood)
The walls of tissue surrounding the vein are thin (blood is not travelling in rhythmic pulses)
They have valves to prevent blood pooling at extremities (arteries do not have valves)
Capillaries
Capillaries are involved
Arteries carry blood at high pressure (80 - 120 mm Hg)
They have a narrower lumen (to maintain high pressure) surround by a thick wall made of two layers
The middle layer (tunica media) contains muscle and elastin to help maintain pulse flow (it can contract and stretch)
The outer layer (tunica adventitia) contains collagen prevents the artery rupturing due to the high pressure blood flow
Veins
Veins carry blood under low pressure (<10 mm Hg)
They have a very wide lumen (keeps pressure low and allows greater flow of blood)
The walls of tissue surrounding the vein are thin (blood is not travelling in rhythmic pulses)
They have valves to prevent blood pooling at extremities (arteries do not have valves)
Capillaries
Capillaries are involved