What is the resting phase of the cardiac cycle called?

The resting phase of the cardiac cycle is known as diastole. During diastole, the heart muscle relaxes, allowing the chambers of the heart (the atria and ventricles) to fill with blood. This phase is essential for the heart's pumping action, as it ensures that there is adequate blood volume to be ejected during the next contraction phase, known as systole.

Diastole is characterized by a decrease in pressure within the heart chambers, which facilitates the inflow of blood from the veins. This phase is crucial for the heart's overall efficiency and helps maintain a steady and adequate blood supply to the body during the periods of rest between contractions. Understanding diastole is key to comprehending the cardiac cycle and how the heart functions to ensure proper circulation.