Lowered extracellular K⁺ levels will lower the heart rate because A) the resting membrane potential is hyperpolarized. B) ectopic action potentials occur. C) action potential amplitude declines. D) more Na⁺ channels open. E) it blocks Ca²⁺ channels.

Question

Quizplus · Accepted Answer

Lowered extracellular potassium levels lead to hyperpolarization of the resting membrane potential, making it more negative and thus lowering the heart rate by increasing the threshold for action potential generation.

Lowered Extracellular K+ Levels Will Lower the Heart Rate Because

Lowered Extracellular K⁺ Levels Will Lower the Heart Rate Because