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A : Dub is a long and sharp sound. R :...

A : Dub is a long and sharp sound.
R : It is caused by closing of atrio ventricular valves.

A

If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).

B

If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2).

C

If Assertion is true statement but Reason is false, then mark (3).

D

If both Assertion and Reason are false statements, then mark (4).

Text Solution

AI Generated Solution

The correct Answer is:
To analyze the given assertion and reason, we will break down the information step by step. ### Step 1: Understand the Assertion The assertion states: "Dub is a long and sharp sound." - **Analysis**: In the context of heart sounds, "dub" refers to the second heart sound (S2). This sound is actually shorter and softer compared to the first heart sound (S1), which is referred to as "lub." Therefore, the assertion is incorrect. ### Step 2: Understand the Reason The reason states: "It is caused by closing of atrioventricular valves." - **Analysis**: The "dub" sound is produced by the closure of the semilunar valves (the aortic and pulmonary valves) at the end of ventricular systole. The closure of the atrioventricular (AV) valves (the tricuspid and bicuspid/mitral valves) produces the "lub" sound. Thus, the reason provided is also incorrect. ### Step 3: Conclusion Since both the assertion and the reason are false, we can conclude that: - **Assertion**: False - **Reason**: False ### Final Answer Both the assertion and reason are false.
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