Cardiac cycle

Question 1

Diastole (Relaxation Phase)

Answer 1

• Ventricles and atria are relaxed.
• Blood fills the atria from the veins.
• The atrioventricular (AV) valves open, and blood flows into the ventricles.
• Semilunar valves are closed.
• This phase allows the heart to fill with blood.

Question 2

Systole (Contraction Phase)

Answer 2

• Atria contract to push any remaining blood into the ventricles.
• Ventricles contract, causing the AV valves to close and the semilunar valves to open.
• Blood is pumped from the left ventricle into the aorta and from the right ventricle into the pulmonary artery.
• This phase pushes blood out of the heart.