When studying the nervous system, we learned that he is formed by nervous tissue. This tissue is made up, among other cell types, by the neurons, cells responsible for the propagation of the nerve impulse. We also learned that the nervous system is divided into the peripheral nervous system and the central nervous system, the latter being composed of two parts: the brain and the spinal cord.
When analyzing the central nervous system, it is possible to notice two portions with different colors: a portion with a more gray color and another with a whiter region. The gray region is called gray matter, and the whitish region is called white matter.
Gray matter is made up of a large number of cell bodies of neurons. The white matter, on the other hand, is formed by a portion of extensions of neurons, especially axons. As the axons of some neurons are surrounded by myelin, this substance gives a whitish appearance to the white matter.
→ Location of gray matter and white matter
White and gray matter are found in the central nervous system, more precisely in the brain (a part of the brain) and in the spinal cord. In each of these regions, they are arranged in different locations.
In the brain, it is possible to observe that the gray matter is in the outermost region of the organ and in more centralized places called the nuclei. The white matter is found inside the organ.
In the medulla, the gray matter is H-shaped.
In the spinal cord, the arrangement of these substances is different. The gray matter is arranged in the shape of an H in the inner part of the medulla. The white matter presents itself more externally (See the figure above).
By Ma. Vanessa dos Santos
