Question

what is the immediate result of the opening of sodium channels along the sarcolemma (beyond the motor end plate)?

generation of an action potential

release of acetylcholine into the synaptic cleft

relaxation of the muscle fiber

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Explanation:

When sodium channels open along the sarcolemma (beyond the motor - end plate), sodium ions rush into the cell. This influx of positive charge depolarizes the membrane, leading to the generation of an action potential. Acetylcholine is released from the motor neuron into the synaptic cleft before sodium channels open. Muscle fiber relaxation occurs when calcium is pumped back into the sarcoplasmic reticulum and cross - bridges detach, not as a result of sodium channel opening.

Answer:

Generation of an action potential