25. ECG and Exercise – Flashcards
Unlock all answers in this set
Unlock answersquestion
The electrocardiogram measures:
answer
the electrical activity of the heart.
question
In the atria, the depolarizing phase of the action potential creates:
answer
the P-wave.
question
In the ventricles, the depolarizing phase of the action potential is associated with:
answer
the QRS complex.
question
The heart rate can be calculated if you know the time interval between:
answer
the R-wave and the next R wave.
question
If the action potentials do not change and the timing between the atrial and ventricular action potentials remain constant, which time interval will change when the heart rate increases?
answer
the time interval between T-wave and the next P-wave.
question
Einthoven's triangle is formed by:
answer
three electrodes placed on the skin of the subject.
question
The P-R interval correlates with depolarization of the atria followed by:
answer
depolarization of the ventricles.
question
The R-T interval correlates with depolarization of the ventricles followed by:
answer
repolarization of the ventricles.
question
The T-P interval correlates with repolarization of the ventricles followed by:
answer
depolarization of the atria in the next cardiac cycle.
question
The R-R interval correlates with:
answer
one cardiac cycle to the next successive cardiac cycle.
question
Exercise decreases the R-R interval. Which of the following intervals decreases by a comparable amount?
answer
The T-P interval decreases substantially.
question
If the P-R interval is not changed by exercise, this observation indicates that:
answer
exercise does not change the duration of the atrial action potential.
question
If the R-T interval is not changed by exercise, this observation indicates that:
answer
exercise does not change the duration of the ventricle action potential.
question
If the T-P interval is reduced by exercise, this observation indicates that:
answer
exercise changes the timing between cardiac cycles.
question
If the T-P interval is reduced by exercise, what happens to the time course of coronary blood flow when the heart rate increases during and immediately after exercise?
answer
There is a decrease in the duration of the coronary blood flow between cardiac cycles.
