Topic: Skeletal Muscle a. What is a motor unit?

b. For a skeletal muscle fiber to contract, it must receive a stimulus from its motor neuron. This occurs within the neuromuscular junction (NMJ).

Discuss the ENTIRE mechanism of skeletal muscle fiber contraction at the NMJ: beginning with the mechanism for release of neurotransmitter from the pre-synaptic motor neuron and continuing through the entire mechanism leading to the contraction of the skeletal muscle fiber.