The region where the end of an axon from a neuron comes into close contact with a muscle fiber is called a motor end plate/neuromuscular junctions.
Explanation:
Neuromuscular junction is the connection between end of the axon terminal and the muscle fiber. It is the site of transfer of signal from the neuron to the target muscle. The action potential is generated at the axon terminal which causes the calcium channel to open releasing the neurotransmitters into the synaptic cleft. The acetylcholine which is the neurotransmitter then bind to the receptors on the muscle which opens the sodium channels and it is released into the muscle which causes the depolarization of the muscles. The calcium ions then enters the cells and the muscles contract.