Blood Vessels Flashcards
what is the main purpose of arteries
pump blood away from heart
where does exchange occur
microcirculation
what is the purpose of veins
return blood to the heart
what are the four components of a vein
tunica externa tunica media tunica intima endothelium lumen
what are the four components of an artery
tunica externa tunica media internal elastic membrane endothelium lumen
what are the characteristics of elastic arteries
large lumen
low resistance
elastins in all tunics
smooth out large pressure changes
what are the characteristics of muscular arteries
deliver blood to organs
thick tunica media
more smooth muscle
active in vasoconstriction
what is an arteriole
the smallest arteries
deliver to capillaries
control flow into capillary beds via vasodilation and vasoconstriction
what is a capillary bed
interconnected beds of arteries
what occurs at capillary beds
exchange between blood and cells
characteristics of capillaries
thin tunica interna
one red blood cell goes through at any time
how many cells thick are capillaries
1 cell thick
what are the three types of capillaries
continuous
fenestrated
sinusoid
where are the continuous capillaries found
skin
muscle
brain
where are fenstrated capillaries found
kidneys
small intestine
endocrine glands