Veins carry blood towards the heart

The walls of the vein are thin/flexible

Under low pressure they carry deoxygenated

blood.

One exception to this is the pulmonary vein.

Veins rely on the Veins rely on the skeletal muscle to squeeze

blood along.

Some veins also have valves, for example in

the leg where blood goes against the flow of

gravity

Veins are made up of endothelial lining,

smooth muscle and also elastic tissue.

The most common vein we use to place an The most common vein we use to place an

IVC is the cephalic vein

Others, such as saphenous could also be

used. As well as the marginal ear veins.

Capillaries, arteries and veinsfill in the gaps

Made up a single layer of endothelial cells capillaries are small and

permeable. As well as the uptake of nutrients metabolic waste

products are also removed.

Blood flows slowly due to their small diameter and crucially this is

also where gaseous exchange also occurs.

Under high pressure arteries will carry

blood away from the heart.

Mostly they will transport oxygenated blood

to the tissue and organs, however the

pulmonary artery carries deoxygenated

blood back to the lungs

Small branches of arteries are called Small branches of arteries are called

arterioles Some organs, such as the brain

have a network of arteries known as ‘end

arteries’ meaning once they are blocked,

with a clot the blood supply becomes

compromised.