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Question
Answer in only one sentence of the following question:
Mention the role of the pacemaker in human heart.
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Solution
- The Sinu-auricular (SA) node is the pacemaker of the heart.
- It generates wave of contraction which spread along the wall of atria and bring about their contraction.
- It has highest degree of rhythmicity and is the first to originate the cardiac impulses and determine the rate of heart beat.
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