The Blood Vessels Roadways of the Body

What do Blood Vessels Do? Carry Blood! Exchange nutrients, wastes, and gases with tissues Transport Help maintain blood pressure Direct blood flow to tissues (when increased or decreased blood flow is required)

Three types of blood vessels Arteries Veins Capillaries

Three major parts of blood vessels: Tunica Intima: The innermost layer; consists of simple squamous epithelium Tunica Media: The middle layer; consists of smooth muscle and elastic and collagen fibers Tunica Adventia: The outermost layer; consists of connective tissue

Arteries: Thick muscular walls Blood moving under high pressure and speed Blood is oxygenated (except pulmonary arteries) Always take blood away from the heart Branch into arterioles Arterioles branch into capillaries

Capillaries: Consist of a single layer of endothelium only one cell thick The site of nutrient, waste, and gas exchange between the blood and the body cells

Veins: Capillaries flow into venules Venules flow into veins Veins have thinner walls Blood moves under lower pressure and slower speed Veins need valves to keep blood moving in the correct direction Always take blood to the heart Carry deoxygenated blood (except the pulmonary veins)

Heart Vessels: Right common carotid artery Right internal jugular vein Right subclavian artery Brachiocephalic artery Brachiocepahlic vein Superior vena cava Left common carotid artery Left internal jugular vein Left subclavian artery Aortic arch

Major Arteries: Brachial Ascending aorta Subclavian Common carotid Brachiocephalic Descending aorta Coronary Abdominal aorta Common illiac femoral

Major Veins: Brachial Brachiocephalic Jugular Subclavian Superior vena cava Coronary Inferior vena cava Iliac Femoral Great saphenous