Bio 436 Final Exam Questions and
Correct Answers
Cardiac output (CO) ✅cardiac output is the amount of blood pumped out by each
ventricle in one minute. Cardiac output is directly related to heart rate and stroke
volume, normally 5.25 L/min
CO = HR x SV
End diastolic volume (EDV) ✅volume of blood in ventricles at end diastole
- one of the variables that go into SV
Stroke volume (SV) ✅the amount of blood pumped/ejected by each ventricle with each
heartbeat, averaging 70 ml per beat in the adult at rest
3 variables:
- EDV
- Total peripheral resistance
- contractility
End systolic volume (ESV) ✅the amount of blood left after ventricular ejection
- normally around 65 ml
Myocardium ✅heart muscles...left side has more than right side
Semilunar valve ✅what makes the "dub" sound, valves before the pulmonary and
systemic circuit
Bicuspid/mitral valve ✅valve that is in-between the left atria and left ventricle
- partially responsible for the "lub" sound
Tricuspid valve ✅valve that is in-between the right atria and right ventricle
- partially responsible for the "lub" sound
Cardiac cycle ✅physical and mechanical events that happen in the heart
- is controlled by the electrical events
Ventricular systole ✅- contraction of the ventricles
Events include:
- EDV
- isometric ventricular contraction
- ventricular ejection
- ESV
, Isovolumetric contraction ✅a defined volume of blood within the ventricles that we are
contracting against
- first phase of ventricular contraction pushes AV valves closed but does not create
enough pressure to open semilunar valve
"LUB"
Isovolumetric relaxation ✅as ventricle relax pressure in ventricles drops, blood flows
back into cups of semilunar valves and snaps them closed
"DUB"
Ventricular ejection ✅as ventricular pressure rises and exceeds pressure in the
arteries, the semilunar valves open and blood is ejected
- only about 60%
Pulmonary artery ✅vessel that leads to the lungs from the right ventricles
Pulmonary vein ✅vessel that connects the lungs back into the heart, left atrium
Frank-starling law of the heart ✅The more you fill the ventricles, the more will be
pumped out without altering anything to the heart
- a length-tension relationship
Venous return ✅the flow of blood back to the heart via veins
- at any one point in time we have 70% of blood in veins
- controls EDV & thus SV and CO
Resistance vessels ✅is small diameter blood vessel in the microcirculation that
contributes significantly to the creation of the resistance to flow and regulation of blood
flow
Vasoconstriction ✅vessels decreasing the diameter of the lumen (more contact of fluid
with wall)
- greater resistance
- greater pressure
Vasodilation ✅vessels increasing the diameter of the lumen (less contact of fluid with
wall)
- less resistance
- less pressure
Capacitance vessels ✅vessels that are very compliant, very stretchy & hold a lot of
blood
- contributes to venous return
Correct Answers
Cardiac output (CO) ✅cardiac output is the amount of blood pumped out by each
ventricle in one minute. Cardiac output is directly related to heart rate and stroke
volume, normally 5.25 L/min
CO = HR x SV
End diastolic volume (EDV) ✅volume of blood in ventricles at end diastole
- one of the variables that go into SV
Stroke volume (SV) ✅the amount of blood pumped/ejected by each ventricle with each
heartbeat, averaging 70 ml per beat in the adult at rest
3 variables:
- EDV
- Total peripheral resistance
- contractility
End systolic volume (ESV) ✅the amount of blood left after ventricular ejection
- normally around 65 ml
Myocardium ✅heart muscles...left side has more than right side
Semilunar valve ✅what makes the "dub" sound, valves before the pulmonary and
systemic circuit
Bicuspid/mitral valve ✅valve that is in-between the left atria and left ventricle
- partially responsible for the "lub" sound
Tricuspid valve ✅valve that is in-between the right atria and right ventricle
- partially responsible for the "lub" sound
Cardiac cycle ✅physical and mechanical events that happen in the heart
- is controlled by the electrical events
Ventricular systole ✅- contraction of the ventricles
Events include:
- EDV
- isometric ventricular contraction
- ventricular ejection
- ESV
, Isovolumetric contraction ✅a defined volume of blood within the ventricles that we are
contracting against
- first phase of ventricular contraction pushes AV valves closed but does not create
enough pressure to open semilunar valve
"LUB"
Isovolumetric relaxation ✅as ventricle relax pressure in ventricles drops, blood flows
back into cups of semilunar valves and snaps them closed
"DUB"
Ventricular ejection ✅as ventricular pressure rises and exceeds pressure in the
arteries, the semilunar valves open and blood is ejected
- only about 60%
Pulmonary artery ✅vessel that leads to the lungs from the right ventricles
Pulmonary vein ✅vessel that connects the lungs back into the heart, left atrium
Frank-starling law of the heart ✅The more you fill the ventricles, the more will be
pumped out without altering anything to the heart
- a length-tension relationship
Venous return ✅the flow of blood back to the heart via veins
- at any one point in time we have 70% of blood in veins
- controls EDV & thus SV and CO
Resistance vessels ✅is small diameter blood vessel in the microcirculation that
contributes significantly to the creation of the resistance to flow and regulation of blood
flow
Vasoconstriction ✅vessels decreasing the diameter of the lumen (more contact of fluid
with wall)
- greater resistance
- greater pressure
Vasodilation ✅vessels increasing the diameter of the lumen (less contact of fluid with
wall)
- less resistance
- less pressure
Capacitance vessels ✅vessels that are very compliant, very stretchy & hold a lot of
blood
- contributes to venous return
