AP BIOLOGY

Detailed explanation-1: -Sinoatrial node (SA node) is located on the wall of the right auricle/atrium, near the opening of the superior vena cava. It relays the impulse that starts a heart beat to the right ventricles with the help of special conducting fibres.

Detailed explanation-2: -The sinoatrial node (SAN), located in the right atrium, serves as the primary site for initiation of the normal heartbeat (sinus rhythm) (Figure 1).

Detailed explanation-3: -An electrical stimulus is generated by the sinus node (also called the sinoatrial node, or SA node). This is a small mass of specialized tissue located in the right upper chamber (atria) of the heart.

Detailed explanation-4: -The SA node called the sinoatrial node lies in the wall of the right atrium near the opening of the superior vena cava.

Detailed explanation-5: -Your sinoatrial node is sometimes called your heart’s natural pacemaker. It sends the electrical impulses that start the heartbeat. The SA node is in the upper part of your heart’s right atrium.