Transportation in Plants and Circulation in Animals — Science STD 10 — Question

The sequence of events occurring from the beginning to the completion of one heart beat is called cardiac cycle. During cardiac cycle blood flows ’ through the chambers of the heart in a specific direction. Each cardiac cycle lasts about 0.8 second. The events during a single cardiac cycle involves

1. Atrial systole: Contraction of auricles (0.1 sec)
2. Ventricular systole: Contraction of ventricles (0.3 sec)
3. Ventricular diastole: Relaxation of ventricles (0.4 sec)