in class review questions for test 2 Flashcards
the heart is 2 pumps, the right pump is responsible for circulating blood where?
the lungs
to the lungs with what vessels?
pulmonary arteries
why are the pulmonary arteries unique?
they carry deoxygenated blood
blood returns to which chamber of the heart
left atrium
returns to left atrium by what vessels?
pulmonary veins
why are pulmonary veins unique ?
they carry oxygenated blood
ultimate purpose of cardiovascular system
get blood into capillaries
arteries close to heart are characterized as
elastic
the arteries have capacity to do what
stretch and expand
2 phases of cardiac cycle, active phase is what
systole
what happens during systole?
heart is beating
when tracing a drop of blood from right atrium, it passes through a valve referred as
right atrioventricular valve
other name besides right AV valve is
tricuspid valve
when it passes through valve, it then enters
right ventricle
it fills right ventricle to
70%
once filled by 70% what happens next
atria contracts
after atria contracts, result is
fills remaining 30% of blood
when ventricle contracts, it must overcome what pressure?
diastolic pressure
diastolic pressure is where
pulmonary artery
when this pressure is overcome, what valve opens?
pulmonary semilunar valve
when heart beats, it is critical that all fibers contract at same time, this is made possible by what in heart tissue?
intercalated discs
in contrast, skeletal muscle fibers should not all contract at once. each skeletal muscle has its own individual
nerve supply
when measuring BP, the cuff is inflated to a level that
closes the artery
the cuff is reduced and the 1st sound heard. what causes the sound?
artery flashes open
the pressure where first sound occurs is the
systolic
at the end of the measurements what happens
the sound disappears
primary control of HR arises from
SA node
external control can arise from the —– which accelerates HR
sympathetic nervous system
at the very beginning of exercise, HR accelerates immediately bc what happens
parasympathetic nervous system stops
where are the baroreceptors located?
in the bifurcation/split of carotid artery
baroreceptors monitor BP to ensure
adequate blood flow to the brain
if BP drops, baroreceptors send signal to
cardiovascular control center
if BP drops what needs to happen
needs to be increase in pressure. CCC tells SNS to increase HR
need HR to go up. know impulse is done by CCC. if HR needs to go up it is accomplished by sending a message through the
sympathetic nervous system
this is all an example of
physiologic control system
if operating effectively, it is operating as a
negative feedback loop
in average sized male, resting cardiac output is approx
5 L
BP in veins is very low because —- empties into veins
capillaries
in order to circulate venous blood to vessels below heart, it needs help. what is one way we are providing help to these vessels below the heart
one way valves
in addition, there may be vasoconstriction and help from
muscle pumps
when it comes to VO2 max. huge factor is ability to deliver oxygen which is determined by central component comprised primarily of
cardiac output
ability to utilize oxygen is determined by peripheral component composed of 3 factors:
mitochondria, myoglobin, and capillaries
SV is controlled by several factors including amount of ventricular filling determined by
venous return
venous return to heart finishes with
EDV
electrical activity of heart begins with pacemaker called
sinoatrial node
from sinoatrial node it then goes to
AV node
from AV node it goes to
AV bundle
from AV bundle it goes to
AV bundle branches
from AV bundle branches it goes to
perkinge fibers
according to who’s law, when cardiac muscle fibers are stretched, something happens
frank starling law
what happens as a result of frank starlings law
greater contraction
when ventricles contract, they empty by
70%
when ventricles contract and empty, this is called
ejection fraction
the packed volume of cells in blood is known as
hematocrit
typically what % of blood
45-50%
blood boosting/doping uses
EPO
EPO is released from
kidneys
EPO acts to
increase RBC production
