Describe the process of an action potential travelling across a synapse

An action potenial reaches the synaptic bouton causing depolarisation which opens calcium voltage gated channels. Calcium moves into the cell and causes the movement of vesicles containing acetylcholine towards the presynaptic membrane here they fuse with the membrane via snare proteins. The acetylcholine is released into the synapse. It then moves across the synapse and binds to acetylcholine receptors on the post synaptic membrane. This causes the opening of sodium channels, the sodium move into the post synaptic neurone reaching the threshold potential causing the opening of more sodium channels resulting in the depolarisiation of the cell and the formation of a new action potential.