Select the correct statement about the function of myocardial cells. Cardiac muscle cells are innervated by sympathetic, parasympathetic, and somatic nerve fibers so that the nervous system can increase heart rate. The refractory period in skeletal muscle is much longer than that in cardiac muscle. The influx of potassium ions from extracellular sources is the initiating event in cardiac muscle contraction. The entire heart contracts as a unit or it does not contract at all.

Select the correct statement about the function of myocardial cells. Cardiac muscle cells are innervated by sympathetic, parasympathetic, and somatic nerve fibers so that the nervous system can increase heart rate. The refractory period in skeletal muscle is much longer than that in cardiac muscle. The influx of potassium ions from extracellular sources is the initiating event in cardiac muscle contraction. The entire heart contracts as a unit or it does not contract at all.

Principles Of Pharmacology Med Assist

6th Edition

ISBN:9781337512442

Author:RICE

Publisher:RICE

Chapter23: Medications Used For Cardiovascular System Disorders

Section: Chapter Questions

Problem 3RQ

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