Types of neurons
Types of neurons Neurons vary in structure, function, and genetic makeup. Given the sheer number of neurons, there are thousands of different types, much like there are thousands of species of living organisms on Earth. However, there are five major neuron forms. Each combines several elements of the basic neuron shape. Multipolar neurons. These neurons have a single axon and symmetrical dendrites that extend from it. This is the most common form of neuron in the central nervous system. Unipolar neurons. Usually only found in invertebrate species, these neurons have a single axon. Bipolar neurons. Bipolar neurons have two extensions extending from the cell body. At the end of one side is the axon, and the dendrites are on the other side. These types of neurons are mostly found in the retina of the eye. But they can also be found in parts of the nervous system that help the nose and ear function. Pyramidal neurons. These neurons have one axon but several dendrites to form a pyramid type shape. These are the largest neuron cells and are mostly found in the cortex. The cortex is the part of the brain responsible for conscious thoughts. Purkinje neurons. Purkinje neurons have multiple dendrites that fan out from the cell body. These neurons are inhibitory neurons, meaning they release neurotransmitters that keep other neurons from firing.