Compare the duration of atrial and ventricular systole at a representative heart rate of 75 bpm.
A)Atrial systole has a duration of 100 msec,and ventricular systole has a duration of 270 msec.
B)Atrial systole has a duration of 270 msec,and ventricular systole has a duration of 100 msec.
C)Atrial systole has a duration of 100 msec,and ventricular systole has a duration of 100 msec.
D)Atrial systole has a duration of 270 msec,and ventricular systole has a duration of 270 msec.
E)Atrial systole has a duration of 100 msec,and ventricular systole has a duration of 370 msec.

Question

Quizplus · Accepted Answer

At a heart rate of 75 bpm, the duration of the cardiac cycle is approximately 0.8 seconds (60 seconds divided by 75 beats per minute). During this time, the atria contract for a shorter duration than the ventricles, as they only pump blood into the ventricles. Atrial systole typically lasts for about 100 msec, while ventricular systole lasts for approximately 270 msec. Therefore, the correct answer is A, where atrial systole has a duration of 100 msec, and ventricular systole has a duration of 270 msec.

Compare the Duration of Atrial and Ventricular Systole at a Representative