Adult Nurse Practitioner Exam Prep

Answer - C - Myocardial cells do not possess an inherent ability to generate an electrical impulse. The pacemaker cells are the ones that spontaneously initiate electrical impulses. Myocardial cells respond in an all-or-nothing manner in such a way that stimulation of one muscle fiber causes the entire muscle mass to contract as a unit. When myocardial cells are stimulated, the impulse spreads throughout the heart muscle. Automaticity, excitability, and conductivity are classified as electrical properties, whereas contractility is classified as electrical.