CVS Practice Test 2025 - Free CVS Practice Questions and Study Guide

The ability to depolarize spontaneously in cardiac cells is referred to as automaticity. This process is crucial for the functioning of the heart, as it allows certain cardiac cells, particularly those in the sinoatrial (SA) node, to generate electrical impulses without external stimulation. This spontaneous depolarization leads to the regular rhythm of heartbeats, enabling the heart to maintain its pumping action effectively.

Automaticity is a critical feature of pacemaker cells in the heart, which creates a baseline rhythm essential for coordinating the heartbeat. The other choices represent different aspects of cardiac physiology: conductivity relates to the ability of the heart cells to conduct electrical signals, contractility refers to the heart muscle’s ability to contract and generate force, and excitability is the ability of the heart cells to respond to stimuli. While all these properties are important for proper heart function, automaticity specifically highlights the self-initiating aspect of cardiac electrical activity.