Initiation of impulse at
muscle
1] An impulse from a nerve causes calcium to enter a synaptic end
bulb.
2] Acetycholine is released and diffuses across the cleft between the nerve and
the muscle cell.
3] Two molecules of Acetycholine bind with receptors on the muscle cell
membranes.
This opens the sodium channel gate.
4] Sodium flows into the cell.
5] The cell is depolarised.
6] Muscle action potential is generated, causing the muscle to contract.
7] Acetycholine is broken down into choline and acetate and returns to the
synaptic end bulb
to recombine.
8] The sodium channel closes and the potassium channel opens.
9] The cell now repolarises.
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