What is a neurotransmitter?

A neurotransmitter is a chemical substance that plays a crucial role in the nervous system by transmitting signals across the synapse, which is the gap between two neurons. When an electrical impulse, known as an action potential, reaches the end of a neuron, neurotransmitters are released into the synaptic cleft. These chemicals then bind to specific receptors on the surface of the next neuron, facilitating the continuation of the nerve impulse. This process is vital for communication within the nervous system, influencing various functions such as mood, memory, and muscle control.

In contrast, hormones produced by endocrine glands have a different function and are involved in regulating various bodily processes through the bloodstream rather than directly transmitting nerve impulses. Proteins that break down glucose serve metabolic functions and do not relate to the signaling role of neurotransmitters. Additionally, while structural components of neurons, such as dendrites and axons, are essential for the overall function and integrity of the nervous system, they do not participate in the transmittance of signals in the same way that neurotransmitters do.