Cardiac cycle

Question

Rearrange the sentences A to H to show the sequence of blood flow during cardiac cycle
A:Atria receive blood from veins and store it prior to each heart beat
B:Ventricular diastole
C:Pressure of Right atrium>Right ventricle-forces tricuspid valve to open
D:Pressure of Left atrium>Left ventricle-forces mitral valve open
E:Atrial systole
F:Atria fill up again to start next cycle. The volume increases while pressure decreases.
G:Ventricular systole
H:Electrical signal picked up by atrial ventricular node.Bundle of his transfer electrical activity down to apex of heart and along Purkinje fibers to initiate contraction of the ventricles.

Answer 1

CARDIAC CYCLE : 1) One systole One diastole is called Cardiac Cycle.

2) One contraction and one relaxation is called Cardiac Cycle.

3)One heart beat is called Cardiac Cycle.

Total Time Period : 0.8 Sec.

1. During systole heart contract and pump the blood through arteries .
2. During diastole heart relaxed and filled the blood in the heart.

Both process occur in every heart beat

STAGES OF CARDIAC CYCLE

1. Atrial Systole : Contraction of Atria
2. Ventricular Systole : Contraction of Ventricles
3. Complete Cardiac Diastole : Relaxation of Atria and Ventricles.

Answer 2

Hi! The correct order should be:

A > E > C > D > B > H > G > F

The justification for this is that:

The cardiac cycle is started by "A", the atria filling up. Then, when the atria contract in "E", the pressure reaches a point that the mitral and tricuspid valves open in "C" and "D". This would lead to blood going into the ventricles in ventricular diastole "B". And, once the signal reaches the ventricles in "H", they contract in systole "G", leading to blood being ejected into the periphery. Then, the whole cycle starts again with "F".