PhysioEx Exercise 6
Delivering single shocks in succession to stimulate the frog heart _______. - ANSdid not
increase the height of the ventricular systole wave
The doublet that results with more frequent stimulation of the frog heart represents _______. -
ANSan extrasystole and an extra contraction of the ventricles
When the ventricles beat rapidly in succession, _______. - ANSa compensatory pause followed
When multiple stimuli were applied at 20 stimuli/sec, _______. - ANSextrasystoles were
produced
The autorhythmicity of cardiac pacemaker cells is made possible by the reduced permeability of
_______. - ANSpotassium
The repolarization of cardiac muscle is due to _______. - ANSpotassium exiting the cell
The total refractory period of cardiac muscle _______. - ANSis longer than the total refractory
period for skeletal muscle
Skeletal muscle is capable of which of the following? - ANSwave summation and fused tetanus
When vagus nerve stimulation was applied to the frog heart, _______. - ANSthe heart rate
slowed and eventually stopped
What part of your tracing illustrates vagal escape? - ANSthe part where the heart resumed
beating
Research shows that in the absence of neural and hormonal influences, the SA node generates
action potentials at a frequency of about 100 times per minute. However, the resting heart rate
is about 70 beats per minute. What would the approximate heart rate be if the vagus nerve were
severed? - ANSabout 100 beats per minute
Which of the following has the fastest rate of spontaneous depolarization? - ANSthe SA node
The effect of the sympathetic nervous system on the heart is to _______. - ANSincrease the
heart rate and increase the force of contraction
Which branch of the autonomic nervous system dominates after a large meal? - ANSthe
parasympathetic branch
Delivering single shocks in succession to stimulate the frog heart _______. - ANSdid not
increase the height of the ventricular systole wave
The doublet that results with more frequent stimulation of the frog heart represents _______. -
ANSan extrasystole and an extra contraction of the ventricles
When the ventricles beat rapidly in succession, _______. - ANSa compensatory pause followed
When multiple stimuli were applied at 20 stimuli/sec, _______. - ANSextrasystoles were
produced
The autorhythmicity of cardiac pacemaker cells is made possible by the reduced permeability of
_______. - ANSpotassium
The repolarization of cardiac muscle is due to _______. - ANSpotassium exiting the cell
The total refractory period of cardiac muscle _______. - ANSis longer than the total refractory
period for skeletal muscle
Skeletal muscle is capable of which of the following? - ANSwave summation and fused tetanus
When vagus nerve stimulation was applied to the frog heart, _______. - ANSthe heart rate
slowed and eventually stopped
What part of your tracing illustrates vagal escape? - ANSthe part where the heart resumed
beating
Research shows that in the absence of neural and hormonal influences, the SA node generates
action potentials at a frequency of about 100 times per minute. However, the resting heart rate
is about 70 beats per minute. What would the approximate heart rate be if the vagus nerve were
severed? - ANSabout 100 beats per minute
Which of the following has the fastest rate of spontaneous depolarization? - ANSthe SA node
The effect of the sympathetic nervous system on the heart is to _______. - ANSincrease the
heart rate and increase the force of contraction
Which branch of the autonomic nervous system dominates after a large meal? - ANSthe
parasympathetic branch
