Which term describes the electrical activity generated by the SA node?

• A. SA node action potential
• B. AV node action potential
• C. Cardiac action potential
• D. Atrial action potential

Answer: (A)

The core idea is the heart’s natural pacemaker producing its own electrical signal. The SA node generates an action potential that starts the electrical cascade, setting the heart’s rhythm. This SA node action potential is the specific electrical activity created by nodal tissue, which then propagates to the atria and onward to the ventricles.

Why this fits best: it names the activity that originates in the SA node itself—the intrinsic pacemaker signal. Other options refer to electrical signals from different tissues or to a broad category of cardiac muscle action potentials, not the SA node’s own signal.

In short, the electrical event produced by the SA node is the SA node action potential.