Artery Categories and Functions
One-way valves in veins
Aid blood flow back to the heart
Veins
Carry deoxygenated blood back to the heart
Arteries
Carry oxygenated blood away from the heart
Categories of Arteries
Conducting arteries (elastic arteries), Distributing arteries (muscular arteries), Arterioles (resistance vessels)
Vasoconstriction
Constriction of blood vessels, increases peripheral resistance
Vasodilation
Dilation of blood vessels, decreases peripheral resistance
Blood Pressure
Force exerted by blood against the walls of blood vessels
Atrial natriuretic peptide
Hormone that causes blood pressure to drop
Aldosterone
Hormone that causes blood pressure to rise
Fastest Blood Flow
In arteries
Slow Blood Flow
In capillaries
Tunica intima
Innermost layer of both arteries and veins
Smooth Muscle
Muscle type present in the middle layer of arteries and veins
Arterial Constriction
Narrowing of arteries, increases peripheral resistance
Vein Valves
Prevent backflow of blood in veins
Blood Flow Regulation
Regulating the diameter of blood vessels
Large veins
Result from the convergence of medium-sized veins, have thick tunica externa
Medium-sized veins
Result from the convergence of venules, have thicker walls and one-way valves
Capillaries
Smallest blood vessels, site of exchange between blood and tissues
Venules
Smallest veins, collect blood from capillaries
Vascular Compliance
Veins' capacity to store varying amounts of blood with almost no change in pressure
Categories of Veins
Venules, Medium-sized veins, Large veins
Arterial Dilation
Widening of arteries, decreases peripheral resistance
