Write any four differences between arteries and veins in mammals.

ARTERIES

VEINS

These distribute blood to the body organs.

These collect blood from body organs.

Arteries are round and have thick walls.

Veins are collapsed/ flattened and have thin walls.

Lumen is small.

Lumen is large.

These carry oxygenated blood except the pulmonary artery.

These carry deoxygenated blood except the pulmonary vein.