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.

Where is the SA node or pacemaker located?

SA node (sinoatrial node) – known as the heart's natural pacemaker. The impulse starts in a small bundle of specialized cells located in the right atrium, called the SA node. The electrical activity spreads through the walls of the atria and causes them to contract.

Where is the SA node located quizlet?

The sinoatrial (SA) node is a section of nodal tissue that is located in the upper wall of the right atrium. The SA node is also referred to as the pacemaker of the heart. Function: Sets the rate of contraction for the heart.