answers correctly solved 2025
Which of the following represents the time it takes for the ventricles to contract
and recover, or repolarize? - correct answer Q-T interval
Depolarization of a myocardial contractile cell occurs as the result of a: -
correct answer Rapid movement of sodium into the cell
There is less laminar flow of blood in a vessel with a smaller radius due to
friction. - correct answer True
Atrial repolarization is not seen as a separate wave on the ECG. - correct
answer True
The sympathetic nervous system influences the rate of depolarization of the
SA node. - correct answer True
The second heart sound results from vibrations generated by the: - correct
answer Closing of the semilunar valves at the start of diastole
The production and conduction of action potentials in the heart produces a
recordable tracing of the electrical activity of the heart called a(n): - correct
answer ECG
The pacemaker of the heart is the AV node. - correct answer False
, Doubling the viscosity of the blood would have more of an affect on peripheral
resistance than doubling the diameter of the blood vessel. - correct answer
False
The T wave in an ECG reflects: - correct answer Ventricle repolarization
Which of the following will increase flow in a vessel the most? - correct answer
Increase radius by 1 unit
How many limb leads are in a standard ECG?6 - correct answer
How does the body decrease the blood vessel radius? - correct answer
Vasoconstriction
Tetanic contractions in cardiac muscle do not occur due to the long absolute
refractory period. - correct answer True
In an electrocardiogram, if a wave of depolarization moves away from a
postive electrode, the ECG tracing shows a(n) __________ deflection -
correct answer Downward
The purpose of having valves in the cardiovascular system is to: - correct
answer Ensure that blood flows in one direction
During the plateau phase of myocardial cell action potentials, the main
electrolyte that is slowly moving into the cell is: - correct answer Calcium
Where is the sinoatrial node located? - correct answer Near the entrance of
the superior vena cava in the right atrium