sinoatrial (SA) node

(noun)

impulse-generating (pacemaker) tissue located in the right atrium of the heart, and thus the generator of normal sinus rhythm

Related Terms

Examples of sinoatrial (SA) node in the following topics:

  • The Cardiac Cycle

    • The internal pacemaker starts at the sinoatrial (SA) node, which is located near the wall of the right atrium.
    • Electrical charges spontaneously pulse from the SA node, causing the two atria to contract in unison.
    • The pulse reaches a second node, the atrioventricular (AV) node, between the right atrium and right ventricle, where it pauses for approximately 0.1 seconds before spreading to the walls of the ventricles.
    • The signal is initiated at the sinoatrial valve.
    • Summarize the caridac cycle and explain the role of the SA node and the AV node in regulating the its rhythm

  • Characteristics of Mammals

    • Mammals also have a specialized group of cardiac fibers located in the walls of their right atrium called the sinoatrial node, or pacemaker, which determines the rate at which the heart beats.