Final answer:
The signal that conducts from the sinoatrial (SA) node to the rest of the heart is called the atrioventricular (AV) node.
Step-by-step explanation:
The signal that conducts from the sinoatrial (SA) node to the rest of the heart is called the atrioventricular (AV) node. After the action potential is initiated at the SA node, it travels through specialized internodal pathways, leading to the AV node. There is a slight delay at the AV node before the impulse is transmitted to the AV bundle, which then travels through bundle branches to the Purkinje fibers and spreads to the contractile fibers of the ventricle.