blood vessels - westmont college · transports blood away from heart to body systemic arteries...
TRANSCRIPT
Blood VesselsThe tubes that transport the blood
The Basics Arterial system takes
blood away from theheart
Venous system takesblood back toward theheart
Arteries (aa) and arterioles (a-ole) Thick middle muscular wall layer Blood pressure (bp) is typically measured
here Largest are aorta and pulmonary arteries
Arteries (aa) and aterioles (a-ole)
Veins (vv) and venules (v-ule) Carry blood toward the heart “Capacitance” vessels Thin, inconstant middle muscular wall layer Under little or no blood pressure Some vv contain pocket valves that are
formed by folds from the inner wall layer
Veins (vv) and venules (v-ule)
Capillaries connection between a-oles and v-ules Functions for the exchange of:
Oxygen and carbon dioxide Nutrients Waste materials
Usually expand to form extensive capillary beds Essentially contact almost all cells of the body other
than e.t.
Capillaries
Blood Circuit Simple Route
Heart arteries arterioles capillaries venulesveinsheart
Wall Structure All blood vessels havethree layers except forcapillaries which onlyhave one.
Tunica Externa (= adventitia) Outermost layer
Loose c.t. with elastinand collagen fibers
Tunica Media Middle layer
Smooth muscle and c.twith elastin fibers
Tunica Intima Innermost layer
Endothelium(= epithelium)
Simple squamous e.t. +basal lamina + c.t.