What do arteries do and have?
•carry oxygenated blood away from the heart
•thick artery wall as blood is at high pressure
•narrow lumen to maintain high pressure
•tunica intima lined with endothelium which unfolds/ folds so the lumen can expand (when blood flow increases). smooth so less resistance to flow of blood. Have a thin layer of elastic tissue for stretch and recoil to maintain BP
•tunica media has thick muscular walls to withstand and maintain high pressures
•tunica adventita has smooth mucle to contract/constrict the lumen. Has a thick layer of collagen and elastic tissue.
