A neurotransmitter is a chemical substance that is released at the end of a nerve fiber by the arrival of a nerve impulse and, by diffusing across the synapse or junction, causes the transfer of the impulse to another nerve fiber, a musclefiber, or some other structure.
Functions of Neurotransmitters:
Neurotransmitters play a crucial role in the communication between neurons (nerve cells) in the nervous system. They are involved in various physiological processes including: