MEDICAL PHYSIOLOGY

Detailed explanation-1: -Arteries and arterioles have relatively thick muscular walls because blood pressure in them is high and because they must adjust their diameter to maintain blood pressure and to control blood flow.

Detailed explanation-2: -Arteries are composed of smooth muscle allowing constriction and dilation through the parasympathetic nervous system. Arteries are deep under the skin. They do not have valves to prevent blood from flowing backwards. Instead, every time the heart beats, the arteries stretch out so the blood has room to go through.