Question

Assertion: Backflow of blood can happen in the pulmonary trunk.
Reason: Pulmonary trunk is not guarded by any valves.

• A. Both the assertion and reason are true and the reason is the correct explanation for the assertion
• B. Both the assertion and reason are true but the reason is not the correct explanation for the assertion
• C. Assertion is true but the reason is false
• D. Both the assertion and reason are false

Answer 1

The correct option is D Both the assertion and reason are false

The right ventricle pumps out the deoxygenated blood from the heart through the pulmonary trunk. The pulmonary trunk is further divided into left and right pulmonary arteries that supply deoxygenated blood to the lungs.
Three half-moon shaped pockets are located at the base of the pulmonary trunk in the heart, which are known as pulmonary semilunar valves. These valves allow the free and forward flow of blood. The backflow of blood is prevented by these valves present in the pulmonary trunk.
So both the statements of assertion and reason are false.