Question

Which of the following terms refers to the period when the heart is at rest?

1) Quiescent period
2) Atrial systole
3) Isovolumetric contraction
4) Ventricular ejection
5) Isovolumetric relaxation

Answer 1

I think 1 or 4 because we have read at class 9 soo

Answer 2

The term for the period when the heart is at rest is the quiescent period, which coincides with the isovolumetric ventricular relaxation phase during the early phase of ventricular diastole in the cardiac cycle.

Step-by-step explanation:

The term that refers to the period when the heart is at rest is quiescent period. This period occurs during the cardiac cycle, which is the period of time between the onset of atrial contraction (atrial systole) and ventricular relaxation (ventricular diastole).

The cardiac cycle includes phases of both relaxation (diastole) and contraction (systole). During the early phase of ventricular diastole, the ventricles are relaxing and this phase is also referred to as the isovolumetric ventricular relaxation phase or isovolumetric relaxation. In this phase, the ventricular muscle relaxes, the pressure within the ventricles falls, the semilunar valves close to prevent backflow, and since the atrioventricular valves remain closed there is no change in volume, hence the term 'isovolumetric' or 'isovolumic'.