axon terminal of somatic moter neuron.
1.somatic motor neuron releases ACh at neuromuscular junction.
2.Net entry of Na through Ach receptor-channel initiates a muscle potential.
3.Action potential in t-tubule alters Conformation of DHP receptor.
4.DHP receptor opers RyR Ca reiease channels in SarCoplasmic reticulum and Ca enters cytoplasm.
5.Ca binds to troponin,allowing actin-myosin binding.
6.Myosin heads execute power stroke.
7.Actin filament slides toward center of sarcomere.