week 6 Flashcards
what occurs at capillaries
fluid exchange
what helps blood distribution
vascular shunt
why is capillaries good for exchange
thin
what is the resistance for arteries
150-300um
what has the least resistance
capillaries
what is the resistance for arterioles
30-150um
terminal arterioles resistance is
10-30um
what is hyperemia
blood flow increases in relation to metabolic activity of a tissue / organ
ph decreases due to what
lactate production during exercise and dilation of blood vessels
what allows dialtion
nitrous oxide from synthase
blood flow what to skeletal muscle during exercise
increases
what percent of blood during maximal exercise to skeletal muscle
80-85%
what does the heptatic artery do
filter bad nutrients compared to the blood going to the portal vein
what is the splanic circulation
liver , gi tract, pancreas and spleen
what is the total blood volume in the splanchnic reigon
20-25%
constriction in splanich circulation can add blood volume into the circulation - increasing what
venous return
what ml in skin during rest
100-300
what is maxmial volume of blood in skin
7-8L
skin is a part of what circulation
cutaneous neural control
what controls skin vasoconstrictor
adrenergic - non hairy skin
what is a dilator within the skin
hairy skin
noepe is a NT for what
adrenergic
acetyle coa is a NT for what
cholinergic
cold leads to
vasoconstriction
what activity is linked to cold stress
sympathetic constrictor activity
what is linked to sympathetic constrictor activity
adrenergic
what is linked to sympathetic dilator activity
cholinergic
skin circulation can determine what
the performance of the heart
heat impacts blood flow causing what
filling of heart is reduced due to less blood in the core
after exercise there is an increase in what
waste in urine and blood due to reduced blood flow in kidneys due to exercise
fick equation shows what
o2 delivery to muscles increases with exercise intensity due to rising Q and arteriovenous return
20-25 % of blood flow is always where
brain
aerobic fitness and brain blood flow are
linked
what is a doppler
measures blood velocity as an index flow
what is NIRS
near-infrared spectroscopy - measures balance of o2 supply at capillary level in cerebral cortical tissue
what can occur with acute CBF regulation
stroke or faint
what can occur with chronic CBF regulation
hypertension, dementia and concussion / tbi
changes in bp post exercise is normal t or f
true
cbf is
cerebral blood flow ( regulation)
what factors does exercise effect
broreflex, Arterial BP, symp + para NS, cardiac output, metabolism
brain blood flow is sensitive to changes in arterial pressure of co2 (PACO2)
true
BBF increases as what increases
exercise intensity
