The impulse is passed to the heart apex after leaving which structure?

The impulse is passed to the heart apex after leaving the AV node. The atrioventricular (AV) node serves as a critical point in the electrical conduction system of the heart. When the sinoatrial (SA) node generates an impulse, it first travels through the atria, causing them to contract and pump blood into the ventricles. The impulse then reaches the AV node, which acts as a gatekeeper, briefly delaying the signal. This delay allows the ventricles to fill with blood properly before they contract.

Once the signal leaves the AV node, it is conducted through the Bundle of His and then down into the left and right bundle branches, which extend into the ventricles and eventually reach the Purkinje fibers. The Purkinje fibers distribute the electrical impulse throughout the ventricular myocardium, leading to a coordinated contraction that begins at the apex of the heart and moves upwards towards the base, effectively pumping blood out of the heart.

The other structures mentioned do not fulfill the function of directly conveying the impulse to the heart apex after leaving the AV node, which is why they are not the correct answer.