Answer:
The charge inside the membrane becomes positive and the muscle contracts
Step-by-step explanation:
The muscle contraction is the result of the generation of the action potential. An action potential is generated in the neuron when the positive ions present outside the neurons move into the neuron.
The resting potential of a neuron is maintained at -70mv which changes to -55mv with the influx of positive ions especially sodium ions. This generates an action potential and when the signal perceived by the brain and sent back leads to the release of the calcium ions from sarcoplasmic reticulum which leads to contraction of muscle.