6 steps of neuromuscular junction

5

ACh binding opens ion channels that allows simultaneous passage of Na+ into muscle fibers and K+ out of muscle fibers. More Na+ ions enter than K+ ions exit, which produces change in membrane potential called "end plate potential"

4

ACh diffuses across synaptic cleft and binds to its receptors on sarcolemma

6

ACh effects are terminated by its breakdown in synaptic cleft by acetylcholinesterase and diffusion away from junction

3

Ca2+ entry causes ACh to be released by exocytosis

1

action potential (AP) comes from central nervous system and arrives at axon terminal of motor neuron

2

voltage-gated Ca2+ channels open. Ca2+ enters axon, moving down electrochemical gradient