blood vessels

direction of blood flow through an artery

away from the heart

direction of blood flow through a capillary

between arteries and veins

direction of blood flow through a vein

towards the heart

how many layers does an artery have

3 layers; very thick

how many layers does a capillary have

1 layer that allows for the exchange of gases and nutrients

how many layers does a vein have

3 layers; thin

blood pressure in an artery

high

blood pressure in a capillary

medium

blood pressure in a vein

low

3 types of arteries

* elastic artery
* muscular artery
* arteriole

which type of artery would the aorta be classified as

elastic artery

continuous capillary

have endothelial cells with no fenestrations

fenestrated capillary

have endothelial cells with fenestrations that allow large materials to pass in/out of blood

venule

smallest veins

why do arteries have a thicker tunica media than a vein

* has ability to withstand high blood pressure
* controls blood flow to organs through vasoconstriction and vasodilation

which blood vessel permits the exchange of materials

capillaries

function of valves in veins

function as folds of the tunica interna

2 major mechanisms for venous return

muscular compression pump and respiratory pump

viscosity

how thick and syrupy a fluid is

turbulence

how smooth the blood flow is

factors that would increase blood flow

* higher BP (artery)
* shorter length
* larger diameter (vasodilation)
* decrease blood viscosity & turbulence

factors that would decrease blood flow

* lower BP (vein)
* longer length
* smaller diameter (vasoconstriction)
* increased blood viscosity & turbulence