Question

The influx of sodium atoms across the motor and plate results in the depolarization of the muscle fiber membrane. This is mediated by.

A) Calcium ions
B) Potassium ions
C) Sodium ions
D) Chloride ions

Answer 1

The influx of sodium ions across the motor and plate results in the depolarization of the muscle fiber membrane.

Step-by-step explanation:

The influx of sodium ions across the motor and plate results in the depolarization of the muscle fiber membrane. As the membrane depolarizes, another set of ion channels called voltage-gated sodium channels are triggered to open. Sodium ions enter the muscle fiber, and an action potential rapidly spreads (or "fires") along the entire membrane to initiate excitation-contraction coupling.