HHP 3500 Lecture Notes - Lecture 16: Alpha Motor Neuron, Neuromuscular Junction, Skeletal Muscle

• School: University of Iowa
• Department: Health and Human Physiology
• Course: HHP 3500
• Professor: Peterson Clayton

Document Summary

Lecture 16: molecule processes leading to tension generation. How muscle fiber excitation occurs: motor unit. Skeletal muscle fibers are excited by somatic alpha motor neurons. 1 specific neuron divergences to touch all the muscle fibers. Nervous system activates one motor neuron, but activates all the fibers within that motor unit; occurs in all or none fashion: neuromuscular junction-connection between motor neuron and fiber. Synapse between somatic motor neuron axon terminal and motor end plate region on the sarcolemma of the muscle fiber. Terminal has nt, then post-synaptic membrane has many receptors; difference in the muscular junction is that it is. Much bigger than normal synapse; since its so large, a single axon is plenty to cause enough depolarization to reach threshold to lead to action potential firing: events of excitation: Ap travels along alpha motor neuron, to terminal where nt is released at the neuromuscular junction acetyl choline is the nt!