Question 31

Diastole describes the relaxation of the chambers of the heart during the cardiac cycle.

Diastole is the phase of the cardiac cycle when the heart's chambers relax, allowing them to fill with blood. This process is essential for maintaining proper blood circulation throughout the body.

A) Tachycardia

Tachycardia refers to a condition where the heart beats faster than normal, typically over 100 beats per minute. It is not related to the relaxation phase of the cardiac cycle, making this option incorrect.

B) Diastole

Diastole is the correct term for the relaxation phase of the heart's chambers. During this time, the atria and ventricles relax, enabling them to fill with blood in preparation for the next contraction.

C) Systole

Systole is the phase of the cardiac cycle when the heart contracts to pump blood out of the chambers. This is the opposite of diastole and therefore does not describe relaxation, making this option incorrect.

D) Bradycardia

Bradycardia is defined as a slower than normal heart rate, typically below 60 beats per minute. While it involves heart rate, it does not describe the relaxation of the chambers, thus rendering this option incorrect.

Conclusion

Diastole is the only option that accurately describes the relaxation of the heart's chambers during the cardiac cycle. All other options either refer to conditions that affect heart rate or describe the contraction phase of the heart, making them unsuitable in this context.