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Assertion: SA node malfunctioning leads ...

Assertion: SA node malfunctioning leads to disturbance of Heart rate
Reason: SA node is the pacemaker of heart producing electrical impulse for heart contraction

A

If both assertion and reason are true and reason is the correct explanation of assertion.

B

If both assertion and reason are true but reason is not the correct explanation of assertion.

C

If assertion is true but reason is false.

D

If both assertion and reason are false.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the assertion and reason question, we will analyze both statements step by step. ### Step 1: Understand the Assertion - **Assertion**: "SA node malfunctioning leads to disturbance of heart rate." - The SA node (Sinoatrial node) is crucial for the normal functioning of the heart. It generates electrical impulses that initiate heartbeats and regulate heart rate. If the SA node is malfunctioning, it cannot produce these impulses effectively, leading to irregular heartbeats or disturbances in heart rate. ### Step 2: Understand the Reason - **Reason**: "SA node is the pacemaker of the heart producing electrical impulse for heart contraction." - The SA node is indeed known as the pacemaker of the heart. It is responsible for generating electrical impulses that cause the heart muscles to contract. This process is vital for maintaining a consistent heart rate, typically around 72 beats per minute. ### Step 3: Analyze the Relationship Between Assertion and Reason - Both the assertion and the reason are true statements. The reason provides a valid explanation for the assertion. If the SA node is not functioning properly, it cannot produce the necessary electrical impulses, which directly leads to disturbances in heart rate. ### Conclusion - Since both the assertion and the reason are true, and the reason correctly explains the assertion, we can conclude that the correct answer is that both statements are true and the reason is a correct explanation of the assertion. ### Final Answer - Both the assertion and the reason are true, and the reason correctly explains the assertion. ---
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