The central nervous system is the spinal cord and brain. The substance of the brain in its composition is heterogeneous, it is formed by white and gray matter. White are nerve fibers, their processes, respectively, having a white color. Gray is a collection of nerve cells and processes of these cells.
Spinal cord gray matter
It is formed by a very large number of neurons of three types, which are grouped into nuclei: radicular cells, bundle neurons, internal cells. It is located inside, and is surrounded by white matter. It is more developed in the cervical and lumbar, which is associated with an increase in motor neurons.
In the center there is a central channel that runs along the entire length of the spinal cord, which is why it is central. Contained in the canal is cerebrospinal fluid. It is surrounded by gray matter, which is called an intermediate substance. Here, gray matter can be divided into paired front, paired rear and side columns. Accordingly, on the cross-section, three horns are distinguished: front, side and rear.
Gray matter of the brain
The spinal cord passes, without any changes, into the medulla oblongata. The border that forms between the oblong and dorsal is the place where the roots of the first pair of nerves of the spinal cord come from . The departments of the upper part are thicker than the lower. In the oblong brain there are nuclei responsible for balance, coordination, metabolism, blood circulation and respiration. The hindbrain consists of two parts: the bridge and cerebellum.
A bridge is a white cushion located on the side of the base of the brain. In front you can see the border with the legs of the brain, and behind - with the medulla oblongata. On a cross-section, white matter is visible, as well as gray nuclei. The extension of the medulla oblongata is the dorsal part of the bridge, in which the nuclei of the sensory systems and cranial nerves are located. Here the gray matter of the brain predominates . The cerebellum is located under the occipital part of the brain. It consists of the hemispheres and the middle part - the worm. A worm connects two hemispheres. The cerebellum covers the layer of gray matter that makes up the cerebral cortex, forming convolutions. White matter penetrates the gyrus. On top of them is the gray matter of the brain. The sectional image is very similar to a tree.
Among the nuclei of gray matter, the most important and most significant is the red nucleus, which serves as the focal point. The water supply to the midbrain is a narrow canal, the length of which is two centimeters. It connects the ventricles, the third and fourth. This channel frames the gray matter of the brain, which is central and consists of small cells. In the diencephalon, the substance consists of nuclei belonging to the centers located under the cortex and responsible for all types of sensitivity. The final brain consists of two parts, two hemispheres. The cerebral cortex is the gray matter of the brain in the form of a thin plate. It is formed by nerve cells in large numbers. These cells can be divided into layers. Each layer, in turn, has its own specific features.
So, gray matter is a cluster of neurons and dendrites. Accumulation occurs in the central nervous system, which is formed by the spinal cord and brain. This substance forms the cerebral cortex, as well as the subcortical nuclei. The substance located in the spinal cord is formed by nerve cells, of which there are about thirteen million. The amount of gray matter contained in the brain can affect the level of development of intelligence. It is assumed that the additional volume of gray matter allows you to process information much faster.