Question

Arrange the following events in the correct order.

I. Atrial systole
II. Ventricular diastole
III. Joint diastole
IV. Ventricular systole
V. Atrial diastole

• A. II, III, I, IV, V
• B. III, I, IV, V, II
• C. III, IV, I, V, II
• D. I, II, III, IV, V

Answer 1

The correct option is B III, I, IV, V, II

Joint diastole is when both the atria and the ventricles are in a relaxed state. It lasts for aboout 0.4 seconds.

Atrial systole is when both the atria undergo contraction and the blood flows from the atria into the ventricles. It lasts for 0.1 seconds.

Ventricular systole is when the right and the left ventricles contract and push the blood into the pulmonary artery and the aorta, respectively. It lasts for about 0.3 seconds.

Atrial diastole is when the atria are relaxed and get filled with the deoxygenated blood in the right atrium and the oxygenated blood in the left atrium. This happens as the ventricles are undergoing systole.

Ventricular diastole is when the pressure in the ventricles fall and the atria are undergoing systole. The right ventricle gets filled with the deoygenated blood and the left ventricle gets filled with oxygenated blood.

All these events are collectively called as the cardiac cycle.