Synapse

Synapse -> The junction between two cells, is where two cells communicate with each other.

Presynaptic cell -> The cell that transmits a signal toward a synapse

Postsynaptic cell -> The cell that receives the signal

Neurotransmitter -> Chemical medium through which signals flow from one neuron to the next at chemical synapse

There are two fundamentally different types of synapse :

• In an electrical synapse, the presynaptic and postsynaptic cell membranes are connected by special channels called gap junctions that are capable of passing electric current, causing voltage changes in the presynaptic cell to induce voltage changes in the postsynaptic cell. The main advantage of an electrical synapse is the rapid transfer of signals from one cell to the next.

• In a chemical synapse, the presynaptic neuron releases a chemical called a neurotransmitter that binds to receptors located in the postsynaptic cell, usually embedded in the plasma membrane. The neurotransmitter may initiate an electrical response or a secondary messenger pathway that may either excite or inhibit the postsynaptic neuron. Because of the complexity of receptor signal transduction, chemical synapses can have complex effects on the postsynaptic cell.