Question

if the sa node is nonfunctional, which of the following is most likely to occur? multiple choice the heart will go into asystole (stop). tachycardia will develop. another portion of the heart will become the pacemaker. the heart will go into defibrillation. the heart will be desensitized.

Explanation:

The SA (sino - atrial) node is the natural pacemaker of the heart. When it is non - functional, other parts of the heart, such as the AV node or Purkinje fibers, can take over the role of generating electrical impulses and act as a pacemaker. Asystole would not be the immediate result as there are backup pacemaker sites. Tachycardia is not the most likely as the heart is losing its primary pacemaker. Defibrillation is a treatment for abnormal rhythms and not a natural consequence of SA node failure. Desensitization is not related to SA node non - functionality in this context.

Answer:

Another portion of the heart will become the pacemaker.