Ch 15 Flashcards
blood flow again
aorta
arteries
arterioles
capillaries
venules
veins
vena cavae
right atrium
tricuspid
right ventricle
pulmonary valve
pulmonary artery
lungs
pulmonary veins
left atrium
mitral valve
left ventricle
aortic valve
aorta
arties, arterioles properties
stiff and spongy
thick smooth muscle and elastic
large amt of fiber
smaller arterioles have less elastic and more muscle
venules, veins properties
more numerous than arteries
larger diameter
hold larger volume
close to skin surface
vascular tone refers to
diameter of vessels
capillaries properties
smallest vessel
site of exchange
lack smooth musce and elastic tissue reinforcement, which faciliatates exchange through a layer of endothelium
metarterioles can act as
bypass channels
partially surrounded by smooth muscle
angiogenesis
new blood vessel development
necessary for normal development
wound healing and uterine lining growth
angiogenesis is controlled by
cytokines
stimulate (VEGF and FGF)
inhibit (angiostatin and endostatin)
elastic recoil in arteries pt 1
ventricle contracts
semilunar valve opens
aorta and arteries expand and store pressure in elastic walls
elastic recoil in arteries pt 2
isovolumic ventricular relaxation
semilunar valve shuts, preventing flow back into ventricle
elastic recoil of arteries sends blood forward into rest of circulatory system
blood pressure is highest in the _____ and ______ as it flows through the circulatory system
arteries;
decrease continuously
MAP =
diastolic + 1/3(pulse pressure)
korotkoff sounds
systolic and diastolic sounds through pressure guage
mean arterial pressure is a function of
cardiac output x resistance
blood pressure includes rapid responses from _______ and slower responses from ______
cardiovascular system;
the kidneys
resistance of the system to blood is determined by ______, while relative distribution of blood between arterial and venous blood vessels is determine by ______
diameter of arterioles;
diameter of the veins
arteriolar resistance is influenced by
local control - based on metabolic needs
sympathetic reflexes - mediated by CNS
hormones - control salt/water balance through kidneys
slide 26?
perhaps
sympathetic control uses
SNS: NE
medulla: Epi
hyperemia is a
locally mediated increase in blood flow
reactive hyperemia
tissue blood flow is down due to occlusion
arteriole diameter is controlled by
tonic release of NE
more release - constriction
less release - dilation
blood traveling takes the path
of least resistance
tissue that demands more will need
more capillaries
when precapillary sphincters are relaxed
blood flows through all capillaries in the bed
if precapillary sphincters constrict
blood flow bypasses capillaries completely and flows through metarterioles
bone marrow, liver, and spleen do not have
typical capillaries but instead sinusoids
continuous capillaries
most common
continuous
pass smaller molecules
found in muscle, CT
BBB
fenestrated capillaries
associated with pores
pass larger molecules & volumes
found in kidney and intestine
velocity of flow depends on
XSA of vessels
absorption
fluid movement into capillaries
net absorption at venous end
filtration
fluid movement out of capillaries
caused by hydrostatic pressure
net filtration at arterial end
bulk flow is regulated by
hydrostatic pressure and osmotic pressure
lymphatic system functions
-returning fluid and proteins to circulatory system
-picking up fat absorbed and transferring it to circulatory system
-serving as filter for pathogens
edema is caused by
inadequate drainage of lymph
filtration far greater than absorption
disruption of balance between filtration and absorption
-increase in hydrostatic pressure
-decrease in plasma protein conc
-increase in interstitial proteins
components of the baroreceptor reflex
carotid - brain
aortic - sys circulation
baroreceptor response to increased blood pressure
decrease symp output
increase parasymp output
baroreceptor response to orthostatic hypertension
increase symp output
decrease parasymp output
cardiovascular disease uncontrollable risk factors
sex
age
family history
CVD controllable risk factors
smoking
obesity
sedentary lifestyle
untreated hypertension
uncontrollable genetic but modifiable lifestyle
blood lipids
diabetes mellitus
LDL build-up leads to
development of athersclerotic plaques
treatment for hypertension
calcium channel blockers, diuretics, beta blocking drugs, ACE inhibitors
