Neuromuscular Junctions Flashcards
0
Q
Why are there many neuromuscular junctions across a muscle fibre?
A
To ensure contraction
1
Q
A neuromuscular junction is where…
A
A motor neurone meets skeletal muscle fibre
2
Q
What is a motor unit?
A
Number of muscle fibres supplied by one neuromuscular junction
3
Q
Explain what happens at a neuromuscular junction
A
1) action potential arrived
2) synaptic vesicles fuse & release
3) acetylcholine diffuses to PSM altering permeability to Na ions
4) Na ion influx, depolarisation
5) acetylcholine broken down by -sterase ( to prevent overstimulation)
6) choline and ethanoic acid diffuse back into neurone, reform acetylcholine using energy from mito.
