Which property describes a cardiac cell's ability to spontaneously depolarize without external stimulus?

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Multiple Choice

Which property describes a cardiac cell's ability to spontaneously depolarize without external stimulus?

Explanation:
Automaticity is the heart’s ability to generate its own electrical impulse. Pacemaker cells in the sinoatrial and atrioventricular nodes naturally reach the threshold and fire an action potential without any external trigger, setting the heart’s rhythm. This spontaneous depolarization is what starts each heartbeat. This differs from excitability, which is the ability to respond to a stimulus with an action potential; conductivity, which is the ability to propagate that impulse through the cardiac tissue; and contractility, which is the ability of cardiac muscle to shorten and generate force.

Automaticity is the heart’s ability to generate its own electrical impulse. Pacemaker cells in the sinoatrial and atrioventricular nodes naturally reach the threshold and fire an action potential without any external trigger, setting the heart’s rhythm. This spontaneous depolarization is what starts each heartbeat.

This differs from excitability, which is the ability to respond to a stimulus with an action potential; conductivity, which is the ability to propagate that impulse through the cardiac tissue; and contractility, which is the ability of cardiac muscle to shorten and generate force.

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