# What is the order of Synaptic Transmission?

May 25, 2017

1. Neurotransmitter synthesis
2. Packaging
3. Release
4. Binding
5. Stopping the chemical signal

#### Explanation:

Electrical information is conducted through the body along neurons. But neurons are not infinitely long (although some can be pretty long and measure above 1 m in length) and they “synapse” on each other.

The problem is that at the point of synaptic junction there is a “gap” between the first neuron and the subsequent one. This gap is called the synaptic cleft (it’s between $10 \text{ nm}$ and $20 \text{ nm}$ large).

The electrical signal cannot “jump” over that gap. Instead, at the point of synaptic junction between two neurons, the electrical signal is “translated” into a chemical message (the neurotransmitter) by the presynaptic neuron (at the presynaptic terminal) – Step 1 & 2.

That chemical diffuses (“swims”) across the synaptic cleft until it reaches the other neuron – Step 2 & 3.

The other neuron then “translates” the chemical signal back into an electrical one – Step 3 & 4.

The chemical message is degraded – Step 5.

This “new” electrical message can now travel down the neuron until it reaches a new synaptic junction.