What are the key components of the electrical system of the heart and what is their function?

The heart's electrical system, also known as the cardiac conduction system, is a network of specialized cells, nodes, and pathways that generate and transmit electrical impulses to coordinate the contraction of the heart chambers. It initiates a heartbeat, sets the rate (usually 60-100 bpm), and ensures the atria contract before the ventricles for efficient pumping. Key Components: Sinoatrial (SA) Node: This is the heart's natural pacemaker*, located in the right upper chamber (atrium). It generates the initial electrical signal. Atrioventricular (AV) Node*: Acting as a "gatekeeper," it delays the signal momentarily. This delay allows the atria to contract fully and empty blood into the ventricles before the ventricles contract. Bundle of His & Bundle Branches*: These pathways take the signal from the AV node and conduct it down to the ventricles. Purkinje Fibers*: These fibers distribute the electrical impulse throughout the ventricular muscle, causing the ventricles to contract.