Why does myelination dramatically increase the conduction velocity of action potentials along axons?
Answer and explanation
Correct answer: D. Restricting depolarization to nodes of Ranvier via saltatory conduction
Myelin functions as an electrical insulator that decreases membrane capacitance and increases transmembrane resistance, forcing ionic currents to jump passively from one unmyelinated node of Ranvier to the next (saltatory conduction), greatly accelerating velocity.
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