Blood Vessels Flashcards
what are the 3 main blood vessels
- arteries- carry blood away from the heart
- capillaries- exchange of materials at the tissue
- veins- carry blood to the heart
how do arteries carry blood
under high pressure, walls are strong, thick compared to the lumen
what do they contain to make them strong
thick layers of muscle
what are capillaries
arteries branch into capillaries
what do capillaries have that allows them to exchange substances with cells
permeable membranes to allow diffusion
what do capillaries supply and get rid of
food and oxygen and get rid of waste like carbon dioxide
how thin are their walls
one cell thick, increases the rate of diffusion
what don’t veins need to have because the blood is at a lower pressure
walls don’t need to be so thick
what do veins have to help the blood flow
bigger lumen
what do veins have to help keep the blood flowing in the right direction
valves
how to calculate the rate of blood flow
volume of blood divided by time
