Question

What prevents the backflow of blood inside the heart during contraction?

• A. Valves in the 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 the heart

The correct option is A.

The explanation for the correct option:

Valves are the flap-like structures, that are present between atria and ventricles and in between ventricles and arteries, and they allow the flow of blood only in one direction and prevent the backward flow of blood to the heart.

The explanation for incorrect options:

Option B:

Ventricles contain multi-layer walls as compared to atria and this help to pump out blood from the heart with greater pressure.

Option C:

Atria contain thin-walled chambers and they receive blood from other parts of the body.

Final answer: Valves prevent the backflow of blood inside the heart during contraction.