Cardiovascular System Review Flashcards
What is the function of cardiac output? unit?
= SV x HR
ml/min
the amount of blood ejected in one minute
epicardium
the external surface of heart
Where is the base and the apex in heart?
the base is like the top of the cone
the apex is like the tip of the cone
which part of the heart (base or apex) has more contracting movement?
the apex
what is the direction of inner and outer layers muscle surrounding the heart?
circumference around the heart
Term for heart muscle cells
myocardium
stroke volume (SV)
the amount of blood ejected by the heart in one beat
heart rate (HR)
the amount of beats in one minute
What is the biological character of myocardium?
rich in mitochondria & capillaries
highly oxidative
generate its own electrical signals
can hypertrophy with increased stress
Which chamber has the thickest wall of myocardium? Why?
left chamber
bcs it requires extra muscle to pump blood throughout the body
What is the external surface of the heart (epicardium) covered by?
fat
Where does the heart generate its own electrical signal? Which one is the primarily?
via SA node (primarily)
AV node
what is the direction of between layers muscle surrounding the heart? What is the benefit of this?
oblique and horizontal
to push the blood up & out of the heart
What does the left atrium do? left ventricle?
received oxygenated blood from lung
pump oxygenated blood received from left atrium to whole body
pacemakers cell
the cell that can generates its own electrical signals or carry the electrical signals
Pathway of left atrium received oxygenated blood?
pulmonary veins -> mitral valve -> left atrium
Pathway of left ventricle pumped oxygenated blood to whole body?
left ventricle -> aorta valve -> aorta -> systemic arteries
triscupid valve. What does it do?
the right aortaventricular valve
Allow blood from right atrium to right ventricle
chordae tendineae
the fibrous cord control that control the open and close of atrio-ventricular valves (mitral valve & triscupid valve)
What is the pathway of SA node electrical signals?
SA node -> both atria -> AV node -> ventricular septum -> Bundle of His -> Purkinjie fibers
What fibers are considered to be ventricular conduction system?
bundle of his
What is the direction of electricals spread by Bundle of His fibers? Why it follow this directons?
septum -> apex -> ventricular base
to make sure the septum wall stiffen so when the left ventricle contract, it doesn’t squeeze the right chamber
When electrical signals travel from SA node to AV node, what happen to the signals?
What is the benefit of this?
the signals get slightly delayed
allowing atria to contract and empty blood into ventricle
What does the right atrium & right ventricle do?
received deoxygenated blood from body
pump the deoxygenated blood received from right atrium to lung
When does the AV node transmit electrical impulses?
when SV node doesn’t work properly
What fibers help the electrical signasl delayed from SA node to AV ndoe?
How does it help?
junctional fibers
it has small diameter -> low conductivity & action potentials delayed
pathway of right atrium receive deoxygenated blood?
system veins -> vena cava (superior & inferior) -> triscupid valve -> right atrium
pathway of right ventricle pump deoxygenated blood to lung
right ventricle -> pulmonary semilunar valve -> pulmonary trunnk -> pulmonary arteries -> lung
septum
the heart wall seperates two chambers
What is the AV biscupid valve? Where is it located?
mitral valve
on the left atrium
What are the great vessels?
aorta, pulmonary trunk & vena cava
What do the coronary vessels do?
vessels that supply blood to the heart
What are the characters of Bundle of His?
large diameter fibers with lots of gap junctions
it can adapt rapidly to action potentials
How is the conducting velocity of Perkinjie fiber different from other?
Perkinjie fibers has the greatest velocity of conducting signals
What happen during diastole phase?
atrium passively receive blood either from pulmonary arteries or vena cava
mitral valve/triscupid valve open while aortic valve/ pulmonary semilunar valve close
Where is the electrical signal root that send signals from atrium to ventricle?
AV node
junctional fibers
the fibers that has small diameter to lower conductivity & delay action potentials from SA node to AV node
What is the structure of red arrows? purple arrows?
lumen
smooth muscles
capillaries
the blood vessel that exchange fluids, nutrients & waste product with tissue
atrial systole
the period which atrium pump the last 5-10% blood remain to fill the ventricle
during the systole phase, what valves close/open?
mitral valve/ triscupid valve close
aortic valve/ pulmonary semilunar valve open
The order of vascular system deliver and return blood?
aorta -> ateries -> ateriole -> capillaries -> venules -> veins -> vena cava -> heart
Which blood vessel has the largest wall of smooth muscle?
Why?
the aorta
because it has to deliver blood throughout body
Which blood vessel has the greatest control of blood flow?
arterioles
Assign the color arrows according to ECG peaks?
red = P wave
Yello = QRS complex
Purple= T wave
What is the blood pressure?
the pressure exerted by the blood on the vessel wall
What does the number of arterial pressure consist of two numbers (120/90 mmHg)?
the systole pressures & the diastole pressure
what is the mean arterial pressure? What is the equation to calculate this?
the pressure averaged over the time of heart beat
= DP + SP -DP/3
Which blood vessel has the largest lumen?
Why?
veins
because it needs to return the greatest amount of blood back to heart
Explain what happen according to each peak
P wave =?
QRS complex = ?
T wave =?
atrial systole
ventricular systole
ventricular diastole
As the blood travel from aorta -> arteriole -> arteries -> capillaries, how does the cross sectional area change?
it increases although the area of each vessel gets smaller
What is the blood flow & its unit?
the total amount volume of blood travel in a second (or minute/ hour)
What is the velocity of blood flow?
the total amount of blood volume travel per second per cross sectional area
flow/ cross sectional area (cm3/sec/cm2 = cm/sec)
How does the total blood volume vary? Give example
with body size and state of training
lean body mass & indurance training has higher blood volume
Components of blood
plasma (55-60%)
formed elements (40-45%)
What is the equation of blood flow?
= driving force / resistance to flow
What is the equation of resistance to flow?
(viscosity of blood x length of vessels)/ (radius of vessel)4
What blood vessel does the significant amount of blood stay in?
vein (~65%)
90% of plasma is _____?
7% of plasma is _____?
3% of _____?
water
plasma proteins
small molecules
What blood vessel has the smallest velocity of blood flow?
Why?
capillaries
because it need to exchanges fluids, nutrients & waste with other tissues
What factor significantly influence the blood flow?
the radius of blood vessel
How does the blood flow velocity change in blood vessel system?
it decreases from aorta -> arterioles -> arteries -> capillaries. then increases -> venules -> veins -> vena cava
What are the components of formed elements in blood?
99% of formed elements is ______?
red blood cell, white blood cell & platelets
red blood cell
What happen to % of plasma of blood when exercise intensly in heat?
decrease 10%
What is hematocrit?
the amount of formed elements over the total blood volume
“capacitance” vessel
why is it called this way?
veins
because they can act as reservoir of blood available to be distributed back to the heart
How does the blood return to the heart?
vasoconstriction of smooth muscle
valves in vein insure that blood advance to the heart
contraction of skeletal muscles along the side of veins
inspiration
chemoreceptors
the receptor that monitor the blood level of CO2, pH & O2
where do the chemoreceptors locate?
aortic arch & carotid bifurcation
what happen in the beginning and during exercise?
motor cortex recruits more muscles
signals are sent to cardiovascular center in medulla oblongata -> increase HR & amount blood flow to existing tissues
How does the inspiration help return blood to heart from vein?
inspiration lower the thoracic and increase abdominal pressure -> moving blood from abdominal veins to thorax ->atrium
baroreceptors
the mechanoreceptors that monitor the blood pressure
How many percent does plasma of blood volume consist of? formed elements?
55%-60%
40%-45%
What will happen to the cortical stimulation of medulla when size of muscle mass activated in exercise increase?
they increase
What happen to the % plasma of blood with endurance training?
increase with 10%
Where do the baroreceptors locate?
aortic arch and carotid bifurcation arteries
What is the mechanism of baroreceptors to counter increased BP?
stretches in arterial wall -> baroreceptors activation -> vagus tone increase -> HR decreases
If there is a rise in CO2 or drop in O2, what will result?
the cardiac output increases
