Neurons Neurons

A specialized cell designed to transmit information to other nerve cells, muscle, or gland cells. It is the basic unit of the brain.

A cell body, dendrites, and an axon.

Dendrites extend from the neuron cell body and receive messages from other neurons.

Synapses are the contact points where one neuron communicates with another.

Neurons signal by transmitting electrical impulses along their axons, which can range from a tiny fraction of an inch, to three feet or more.

Selectively permeable, water-filled molecular tunnels that pass through the cell membrane and allow ions - electrically charged atoms -- or small molecules to enter or leave the cell. The flow of these ions creates an electrical current that produces tiny voltage changes across the neuron's cell membrane.

A neurochemical, released at nerve terminals, diffuse across the intrasynaptic space, and bind to receptors on the surface of the target cell. The brain's chemical messenger.

The first neurotransmitter. This chemical is released by neurons connected to voluntary muscles (causing them to contract) and by neurons that control the heartbeat.

Amino acids, widely distributed throughout the body and brain, serve as the building blocks of proteins. Certain amino acids can serve as neurotransmitters in the brain.

These are chains of amino acids linked together. Peptides differ from proteins, which are much larger and have more complex combinations of amino acids.

This neurotransmitter is present in the brain and other tissues, particularly blood platelets and the lining of the digestive tract. It is implicated in sleep, mood, depression, and anxiety. Scientist believe these switches can be manipulated by analogs, chemicals with molecular structures similar to that of serotonin. Drugs that alter serotonin relieve symptoms of depression and obsessive-compulsive disorder.

Endorphins kill pain and cause sleepiness.