MUSCLE PHYSIOLOGY

Detailed explanation-1: -Every skeletal muscle fiber in every skeletal muscle is innervated by a motor neuron at the NMJ. Excitation signals from the neuron are the only way to functionally activate the fiber to contract. Every skeletal muscle fiber is supplied by a motor neuron at the NMJ.

Detailed explanation-2: -A single motor neuron and all the muscle fibers it innervates is known as a single motor unit.

Detailed explanation-3: -A single muscle fiber is controlled by a single motor neuron.

Detailed explanation-4: -As you have learned, every skeletal muscle fiber must be innervated by the axon terminal of a motor neuron in order to contract. Each muscle fiber is innervated by only one motor neuron. The actual group of muscle fibers in a muscle innervated by a single motor neuron is called a motor unit.