CV8 Flashcards
what does a baroreceptor maintain
homeostasis of mean arterial blood pressure
where are the main baroreceptors located
carotid artery
aorta
baroreceptors are _______ active
tonically
what does being tonically active mean
constantly firing APs
what do baroreceptors sense
changes in pressure and stretch of walls
when there is an increase in b blood pressure, baroreceptors will…
increase their firing rate
where do baroreceptors send signals back to
the cardiovascular control centre
what does the CVCC do when it gets a baroreceptor response
initiates an appropriate response
if there is a huge increase in blood pressure, what does the CVCC do?
it activates parasympathetic output to try and resolve the blood pressure
if there is a huge decrease in blood pressure, what does the CVCC do?
it activates sympathetic output to try and bring bp back up
what is bp determined by
cardiac output and peripheral resistance
what is orthostatic hypotension
causes dizziness after laying down for a long time and suddenly standing up
what does orthostatic hypotension trigger
baroreceptor reflex
how fast does baroreceptor activation occur
within 2 heart beats
why does blood pool in lower extremities when you stand up
gravity
what are peripheral chemoreceptors
they sense alterations in blood gas concentration and blood pH
where are peripheral chemoreceptors located
carotid artery
aorta
what does peripheral chemoreceptor activation change within respiratory system
changes the ventilation system within the respiratory system
what is it called when you get a change in output from CVCC in response to some emotional stimuli
vasovagal syncope
what does vasovagal syncope result in
a large increase in parasympathetic output and reduction in sympathetic output
why would someone faint in response to an emotional stimuli
fall in blood pressure fails to activate normal baroreceptor responses
if bulk flow is resulting in fluid moving into the capillaries, _________ is taking place
absorption
if bulk flow is resulting in the fluid out of the capillaries, _______ is taking place
filtration
what is hydrostatic pressure
the pressure in the blood vessels that drives fluid out of the capillaries
what in oncotic pressure
the pressure that drives fluid into the capillaries (plasma proteins)
what is the net filtration from the entire capillary network
loss of 3L of fluid a day from the blood
what do lymphatic vessels do
assist the cardiovascular system with returning fluid and proteins lost throughout the capillaries
where does lymph fluid empty into
venous return
what causes edema
an abnormal accumulation of fluid in the interstitial space
what is the equation of velocity of blood flow
velocity of blood flow = flow rate / cross sectional area
what does the slow velocity (because of cross sectional area) ensure in capillaries
efficient gas and nutrient exchange
