Final answer:
The neuron releases neurotransmitters that depolarize muscle fibers and cause contraction at the neuromuscular junction, where acetylcholine is released and binds to receptors on the muscle fiber.
Step-by-step explanation:
The location where a neuron releases neurotransmitters (NT) that depolarize muscle fiber cells, leading to contractions, is known as the neuromuscular junction. This is a specialized synaptic structure where the axon terminal of a motor neuron releases the neurotransmitter acetylcholine (ACh) into the synaptic cleft. Upon binding to ACh receptors on the sarcolemma of the muscle fiber, it induces a depolarization of the sarcolemma and initiates muscle contraction.