Question

What prevents backflow of blood inside the heart during contraction?

• A. Valves in heart
• B. Thick muscular walls of ventricles
• C. Thin walls of atria
• D. All of the above

Answer 1

The correct option is A Valves in heart

Hint - Flow of blood in the heart is unidirectional in both right and left part of the heart. This unidirectional flow is maintained by flaps like structure.

Part 1 - Heart

• Heart is the blood-pumping organ that pumps blood throughout the body with the help of blood vessels of the circulatory system.
• The heart is divided into two halves: right and left. Both the halves have 1 atrium (upper chamber) and 1 ventricle (lower chamber) each.

Part 2 - Valves

• The atrium and ventricle have valves in between the chambers to prevent the backflow of the blood.
• Between the right atrium and the right ventricle, the Tricuspid valve is present.
• Between the left atrium and the left ventricle, the Bicuspid valve is present.
• The semilunar valve is present between the ventricles and the pulmonary artery and the systemic aorta.

Part 3 - Conclusion

• The four valves present in the heart prevents the backflow of blood inside the heart.
• The thick muscular wall of ventricles (especially left ventricle) helps in sending blood to the entire body with pressure.
• The wall of atria is thinner than ventricles because they have to pump blood just to the ventricles and not to the body.

Final step - The Valves in heart prevent the backflow of blood inside the heart.