Explain synaptic transmission at a cholinergic synapse.

A synapse is a gap between neurons that allows communication between different neurons using chemical messengers or neurotransmitters. Let's start simple and describe the basic structure of the synapse; it contains a pre-synaptic terminal and a post-synaptic membrane. When an electrical impulse travels down the pre-synaptic neuron and reaches the end, i.e. terminal, it triggers the release of vesicles containing neurotransmitters into the synapse. These neurotransmitters travel across the synapse and bind to their specific receptors on the post-synaptic membrane. This results in the opening of channels in the membrane and exchange of ions between the post-synaptic cell and the synapse. Different channels allow different ions to pass into or out of the post-synaptic cell. The type of channel that opens depends upon the neurotransmitter that is released. For example, Acetylcholine (a neurotransmitter) binds to its receptor and allows Sodium ions (Na⁺) to pass into the post-synaptic cell. The positive charge of Na⁺ makes the cell more positive and creates a generator potential in the post-synaptic neuron and allows an electrical signal to travel down that neuron.