The function of the axon terminal is to transmit a neurotransmitter from one neuron to another. The neurotransmitter is released from the end of the axon of one neuron and binds to the dendrites of the target neuron. Neurotransmitters may be classified as excitatory or inhibitory or both, as in the case of dopamine or acetylcholine.
A neuron contains four main parts: the cell body, dendrites, the axon and the axon terminal. The axon is a long projection from the cell body of the neuron that transmits signals from one nerve cell to another. Bundles of axons are known as nerves. The longest axon in the human body is the sciatic nerve. It spans from the base of the spine to the big toe of each foot. Axons in vertebrates are covered in a myelin sheath. The sheath is made of two different types of cells, depending on what branch of the nervous system the axon is located on. Oligodendrocytes make up the myelin sheath on axons in the central nervous system. Schwann cells form the sheath in peripheral system neurons. Both oligodendrocytes and Schwann cells are types of glial cells. The myelin sheath increases the speed at which signals are sent from neuron to neuron.