Blood vessels

Arteries - Structures & Functions

Narrow lumen- maintain high blood pressure

Folded endothelium- can stretch to prevent damage due to high pressure

Thick layer of elastic tissue- expand & recoil to maintain pressure on blood

Vein- structure & function

Valves- prevent back flow of blood

Wide lumen & thin walls- allow neighbouring skeletal muscles to deform vein & move blood

Capillaries

Narrow lumen- causes blood to flow more slowly & allow exchange of gases. Also reduces diffusion distance.

Capillary wall 1 cell thick- reduces diffusion distance.

Form a large network through tissues- increases surface area.

Name the 3 blood vessels

Arteries

Veins

Capillaries