circulation Flashcards
pulse
wave of pressure you can feel anywhere there is an artery close to skin surface
beats/min
blood pressure
how much pressure is being pushed
sphygmomanometer used to measure
how does sphygmomanometer work
cuff goes around arm and squeezes radial artery when it inflates
when it deflates, artery opens
we here Karatkaff sounds
blood perfusion
blood flow to different tissues in out body
perfusion matches need
tissue perfusion
delivers O2 and nutrients to tissues
removes wastes from tissues
exchanges gases in lungs
forms urine in kidneys
blood velocity is ___ related to cross sectional area of vessels
inversely
higher blood vessel area means ___ speed
lower
how is blood velocity locally regualted
by modifying diameter of arterioles
we have more ___ than any other vessels
capillaries
regulation of blood flow mechanisms
- decreased levels of nutrients or O2 causes vasodilation and relaxation of precapillary sphincters
- change in stretch of vessels causes response in smooth muscle of vessel
- angiogenesis increases number and size of vessels
metabolic mechanism of auto regulation of blood flow
decreased levels of nutrients or O2 causes vasodilation and relaxation of precapillary sphincters (delivers more blood!)
myogenic mechanism of auto regulation of blood flow
change in stretch of vessels causes response in smooth muscle of vessel to contract
angiogenic mechanism of auto regulation of blood flow
angiogenesis increases number and size of blood vessels
angiogenesis = production of new blood vessles
how do respiratory gases and lipid soluble molecules pass through capillary?
direct diffusion
passes directly through capillary cells
how do water soluble solutes (small things dissolved in plasma) pass through capillary?
intercellular clefts and fenestrations