Question

The diagram given alongside represents the human heart in one phase of its activity. Study the same and then answer the questions that follow :
(a)Name the phase.
(b)Which part of the heart is contracting in this phase? Give a reason to support your answer.
(c)Name the parts numbered 1 to 6.
(d)What type of blood flows through the parts marked 1 and 2 respectively?
(e)How many valves are closed in this phase?

Answer 1

1. The given diagram represents the phase of ventricular systole.

2. Both the heart ventricles are contracting in this phase since the semilunar valves are open.

3. 1 - Pulmonary artery

2 - Aorta

3 - Pulmonary vein

4 - Left atria

5 - Semilunar valves

6 - Right ventricle

4. Deoxygenated and oxygenated blood flows through pulmory artery and pulmonary vein respectively.

5. Bicuspid and Tricuspid valves are closed in this phase to prevent backflow of blood into atria.