Question

Which of the following is correct?
A. Joint diastole-70% of ventricular filling
B. Ventricular diastole-25% ventricular filling
C. Isovolumetric contraction-20% of ventricular filling
D. Isovolumetric relaxation-30% of ventricular filling
(a)Both A and B
(b)A, B and C
(c)Only B
(d)A, B, C and D

Answer 1

Hint: Diastole is the phase in the cardiac cycle when the heart is in a relaxed state after it has gone under a contraction. In the joint diastole, both atria and ventricles are in a relaxed state.

Complete answer:
In Joint diastole, 70% of the ventricular filling while in ventricular diastole-25% ventricular filling happens. Hence, both options A and B are correct.
Joint diastole- Joint diastole is the phase of the cardiac cycle (alternate contraction and relaxation of heart) during which auricles and ventricles are in the relaxed state. So, during this phase, the blood through veins enters into the respective auricles, and the pressure in the ventricles decreases and becomes lower than the arterial pressure. Then the valve between the auricle and ventricles open and the blood starts filling in the ventricles. This is known as ventricular filling and the ventricles at his stage are 70% filled with blood.
Ventricular diastole- during this phase of the cardiac cycle, only the ventricles are in the relaxed state while the auricles remain in the contracted state. Hence, only 25% of the ventricle filling is possible during the ventricular diastole.
Isovolumetric contraction- It is an event occurring in the early systole(contraction) phase, during which the ventricles contract with no corresponding volume change occurs. This short-lasting portion of the cardiac cycle takes place while all heart valves are still closed.
Isovolumetric relaxation- When the ventricular pressures drop below the diastolic aortic and pulmonary pressure marking the beginning of diastole is called isometric relaxation.
So, the correct answer is, ‘Both A and B.’

Note: The heart has four chambers, the upper two chambers are called the auricles and the lower two chambers are called the ventricles. All the chambers do not beat simultaneously. Right and left auricles to contract simultaneously while right and left ventricles contract after the contraction of auricles has ended. The auricles relax while the ventricles contract.