Final answer:
The electrical signal in the heart travels via the intrinsic conduction system, which includes the SA node, AV node, bundle of His, and Purkinje fibers. This pathway coordinates the contraction of the atria and ventricles.
Step-by-step explanation:
The electrical signal in the heart travels via the intrinsic conduction system. This system includes several components:
The sinoatrial (SA) node initiates the electrical impulse and spreads it throughout the atria.
The impulse then passes through specialized internodal pathways to the atrioventricular (AV) node in about 50 milliseconds.
From the AV node, the impulse travels down the bundle of His and its branches to the Purkinje fibers in the ventricles.
The impulse finally spreads to the contractile cells of the ventricles, causing them to contract and pump blood.
This pathway ensures that the electrical signal moves efficiently from the top of the heart to the bottom, coordinating the contraction of the atria and ventricles.