Which cardiac tissue has the highest rate of spontaneous depolarization?
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Correct answer: Sinoatrial (SA) node
SA node cells depolarise spontaneously at the fastest rate (60–80 bpm) of all cardiac tissues. This dominance allows the SA node to function as the primary pacemaker, overriding the slower intrinsic rates of other conduction tissues.
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More Cardiac Conduction System (SA, AV Nodes) questions
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