Final answer:
The normal electrical conduction pathway in the heart starts with the firing of the sinoatrial (SA) node, which acts as the natural pacemaker. This node initiates the electrical impulses that regulate the heartbeat and propagate through the rest of the conduction system.
Step-by-step explanation:
The normal electrical conduction pathway in the heart starts with the firing of the sinoatrial (SA) node. This specialized group of cells is located in the right atrium of the heart and acts as the natural pacemaker. It initiates the electrical impulses that regulate the heartbeat by setting the pace for the rest of the heart. These impulses then propagate through the rest of the conduction system, including the atrioventricular (AV) node, AV bundle of His, bundle branches, and Purkinje fibers, leading to the contraction of the heart muscle and the pumping of blood.