Conduction System of the Heart

These flashcards cover the key concepts related to the conduction system of the heart, including the SA Node, AV Node, bundle branches, Purkinje fibers, and their roles in heart function.

What is the location of the Sino-Atrial (SA) Node?

It is located in the posterior wall of the right atrium near the entrance of the superior vena cava.

What is the role of the Sino-Atrial (SA) Node?

It acts as the heart's natural pacemaker, initiating the electrical impulses that control the heartbeat.

What is the function of the Atrioventricular (AV) Node?

It receives the electrical signal from the SA Node and delays it before passing it on to the ventricles, allowing the atria to contract before the ventricles.

What structures are involved in the conduction system of the heart?

The conduction system includes the SA Node, AV Node, Atrioventricular bundle, bundle branches, and Purkinje fibers.

What is the significance of the Bundle Branches in the conduction system?

They conduct impulses rapidly to the ventricular myocardium, ensuring coordinated contraction of the ventricles.

What are Purkinje fibers responsible for?

They spread the electrical impulses throughout the ventricles, leading to their contraction.

What are the two types of control for heart contraction?

Intrinsic control (inner regulation by the heart's conduction system) and extrinsic control (regulation by the nervous and hormonal systems).

What ions play a key role in electrical activity within cardiac muscle cells?

Sodium (Na+), Calcium (Ca2+), and Potassium (K+) ions are crucial for initiating and regulating electrical activity in cardiac muscle cells.

What is the term for the electrical potential generated by the pacemaker cells in the SA Node?

Pacemaker potential.

What happens during the repolarization phase of the action potential in cardiac muscle cells?

Potassium ions (K+) exit the cell, leading to a return to the resting membrane potential.