Question

The diagram given below represents the human heart in one phase of its activity. Study the same and then answer the questions that follow:

1. Name the phase.
2. Which part of the heart is contracting in this phase? Give a reason to support your answer.
3. Name the parts numbered 1to6.
4. What type of blood flows through the parts marked 'l' and '2' respectively?
5. How many valves are closed in this phase?

Answer 1

1. Ventricular systole.
2. The right and left ventricles are contracting in this phase. Tricuspid and bicuspid valves are closed.
3.  
   1. Pulmonary artery,
   2. Aorta,
   3. Pulmonary vein,
   4. Left auricle,
   5.  Bicuspid valve (mitral valve),
   6. Right ventricle.
      
      
4. 1. Pulmonary artery: It carries deoxygenated blood.
   2. Aorta: It carries oxygenated blood.
5. Two (bicuspid and tricuspid) valves.