neuromuscular junction Flashcards
what happens to stimulate the neuro musclar junction
impulse arrives at presynaptic neuron
when the impulse arrives at pre-synapticneurons what does it stimulate
ca+ channels open
what does opening of the ca+ channels cuase
ca+ diffuse into presynaptic knob
what does the ca+ fuse with
synaptic vesicles
what happens to these vesicles
fuse with pre-synaptic membrane
what does the fusing to the membrane allow
vesicles release acctylecholine into synaptic cleft
what happens to the acteylcholine
diffuses across cleft binds to receptors om na+ channels on post-synaptic membrane
what are the receptors on the post synaptic membrane
na+channels
what does the acetylbinding to the receptors stimulate
na+ channels open
once the na+ channels are open what happens
na+ enters
what happens wen na+ enters the membrane
membrane depolerises
what does the na+ diffusion cause
an action potential generated and passed through muscle fibres
what is the differance betwee a neuromuscular junction and a cholegernic synapse
neuromuscular links motor neuron to muscle
what is the main mechanism to muscle contraction
sliding filiment mechanism
what happens to the i-band during contraction
i-band becomes narrower