Astrocyte Ependymal cells Tanycyte Microglia. Epineurium Perineurium Endoneurium. Axon hillock. Authority control TH : H2. This article is issued from Wikipedia.
The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files. Example of several unipolar neurons from a nerve ganglion of a velvet worm a primitive arthropod.
Anatomical terms of neuroanatomy. Cell processes, termed dendrites , extend superficially from the cell body into the molecular layer. A small axon arrow emerges from each cell body and runs through the granue cell layer. Note: Axons and dendrites of neurons are normally visible only in special stained sections such as this Golgi preparation. Schematic cartoon of a ventral horn Somatic Efferent SE multipolar neuron. SE neurons have their cell bodies in the CNS; their axons join peripheral nerves and innervate skeletal muscle.
As a multipoar neuron, a number of dendrites and one axon emanate from the cell body. The axon has few if any branches until its termination in a profusion of branches.
The axon is specialized for conducting excitation from the input region to the output region of the neuron. The cell body plus the dendrites of a mulltipolar neuron constitute a "dendritic zone" which receives synaptic input from other neurons. Neurons also have exceptionally high metabolic rates and subsequently require high levels of glucose and oxygen.
The body will go to great lengths to ensure that neurons are adequately fed; in fact, if for some reason the brain detects that it is not receiving adequate amounts of nutrition, the body will shut down immediately i. Title: Neuron-figure-notext. Illustration of key neuronal structures. Structural classification of neurons is based upon the number of processes that extend out from the cell body. Three major groups arise from this classification: multipolar , bipolar, and unipolar neurons.
Multipolar neurons are defined as having three or more processes that extend out from the cell body. Title: Neurons uni bi multi pseudouni. Structural classification of neurons. Bipolar neurons have only two processes that extend in opposite directions from the cell body. One process is called a dendrite, and another process is called the axon. Although rare, these are found in the retina of the eye and the olfactory system.
Unipolar neurons have a single, short process that extends from the cell body and then branches into two more processes that extend in opposite directions.
The process that extends peripherally is known as the peripheral process and is associated with sensory reception. The process that extends toward the CNS is the central process.
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