MICROANATOMY

Detailed explanation-1: -An action potential has three phases: depolarization, overshoot, repolarization. There are two more states of the membrane potential related to the action potential. The first one is hypopolarization which precedes the depolarization, while the second one is hyperpolarization, which follows the repolarization.

Detailed explanation-2: -The SA node (physiologicalpacemaker) starts the sequence by generating an electrical impulse, causing the atrial muscles to contract. From there, the signal travels to the AV node, then through the bundle of His, down the bundle branches, and through the Purkinje fibers, causing the ventricles to contract.

Detailed explanation-3: -The sino-atrial (SA) node. The atrio-ventricular (AV) node. The bundle of His. The left and right bundle branches. The Purkinje fibres.

Detailed explanation-4: -Step 1: Pacemaker Impulse Generation. The first step of cardiac conduction is impulse generation. Step 2: AV Node Impulse Conduction. Step 3: AV Bundle Impulse Conduction. Step 4: Purkinje Fibers Impulse Conduction. 24-Jun-2019