What makes up the neuronal cells that inhabit the nervous system?
Throughout this article we will discuss the different parts of the neurons, as well as their main characteristics and the functions that each of them possess and that make possible the transmission of information throughout the entire nervous system.
What is a neuron?
Neurons are small cells that inhabit our nervous system and are responsible for activating or inhibiting the electrical activity of this. Sun’s main function is to receive electrical stimuli and drive them to other neurons. This stimulus or electrical reaction is known as action potential.
Therefore, the neurons send an infinite number of action potentials between them that make possible the functioning of our nervous system, thanks to which we can move our muscles, feel pain or even dream.
It is estimated that only about 86 billion neurons are housed in our brain. However, at the time of our birth there may be more than 100 billion. The reason for this decrease in the amount is that over the years our brain ages and the number of neurons begins to wane.
However, this does not mean that our neurons can only die. In our day to day, not only the degeneration of neurons occurs, but also their regeneration.
Currently it is believed that our brain is in constant neuronal regeneration. Thanks to the process known as neurogenesis, the creation of new neurons and new neuronal connections takes place. In addition, some studies say that, especially during childhood, we can enhance this birth of new neurons through a series of exercises and activities that exercise our brain.
Main parts of the neuron
As mentioned above, the neuron constitutes the functional and structural unit not only of our brain, but of the entire nervous system. These are formed by different parts, each with specific characteristics and specific functions.
These parts are known as soma or cell body, dendrites and axon.
1. Soma or cell body
The first part we will talk about is the soma or cell body. As its name suggests, the soma is at the center of the neuron, and this is where the metabolic activity of the neuron takes place.
In the soma new molecules are generated and all kinds of essential functions are carried out that make possible the vital maintenance of the cell and its functions,
To carry out these functions and achieve the transmission of information between neurons, each of them must produce enormous amounts of proteins, without which this transmission would not be possible.
In addition, within the cell body we can find some organelles also present in other types of cells such as lysosomes and mitochondria, the Golgi apparatus or the chromosomes that define our genetics. All this is located in the cytoplasm, which constitutes the soma of the neuron.
Finally, fibrillar proteins are also found within the neuronal cytoplasm, which form the cytoskeleton. This cytoskeleton is what gives shape to the neuron and provides a mechanism for the transport of molecules.
Another part that make up the neurons are the dendrites. This denomination makes reference to the numerous prolongations in the form of branches of small size that are born from the neuronal body and whose main functions are those of receiving the stimuli and providing food to the cell.
These extensions function as neuronal terminals, which receive the action potentials of other nearby neurons and redirect them to the cell body or soma. In addition, due to its branched form, along these we find the dendritic spines, small spines in which the synapses that make possible the transmission of bioelectric impulses take place.
Finally, the axon is the main prolongation of the neuron (and the largest). It is responsible for transporting the action potential from the cell body to another neuron.
This prolongation of great length is born from the cellular body or, in some occasions, from a dendrite. Inside we can find the axoplasm, a characteristically viscous substance in which the different organisms of neurons are found.
One of the main characteristics of these axons is that they can be covered with a layer known as myelin sheath, which can enhance or facilitate the rapidity with which action potentials or electrical stimuli are transmitted.
In addition, neurons can be classified into different types according to the length of the axon: Golgi type I and type II neurons, or according to the form of these: pyramidal cells of the cerebral cortex and Purkinje cells.
4. Other neuronal elements
In addition to the main parts of the neuron described above, there are other particles or sections of great importance for the proper functioning of these. Some of these parts are:
Also known as neurolemocytes, these cells coat the axons of the neurons of the peripheral nervous system and form them myelin sheaths.
As mentioned above, some axons have a myelin layer that facilitates the transmission of electrical stimuli in long travels.
This concept refers to the tiny spaces that are in the myelin sheath and its main purpose is to enhance the speed with which electrical impulses are transmitted.