We explain what the different components of these nerve cells are like.
On numerous occasions we have talked about the nervous system, the cells that make it up, their functions and what happens when they do not work properly. Now, what makes up the neuronal cells that inhabit the nervous system?
Throughout this article we will talk about the different parts of neurons, as well as their main characteristics and the functions that each one of them has and that make it possible to transmit information throughout the entire nervous system.
What is a neuron?
Neurons are small cells that inhabit our nervous system and that are responsible for activating or inhibiting its electrical activity. Sun’s main function is to receive electrical stimuli and lead them to other neurons. This electrical stimulus or reaction is known as the action potential.
Therefore, neurons send an infinite amount 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 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 decline.
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 occurs. In addition, some studies assure 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 made up of different parts, each with specific characteristics and specific functions.
These parts are known as the 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 constitutes the center of the neuron, and it is here where its metabolic activity takes place.
New molecules are generated in the soma and all kinds of essential functions are carried out that make possible the vital maintenance of the cell and its functions,
In order to carry out these functions and achieve the transmission of information between neurons, each of them must produce huge 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 cells of another type such as lysosomes and mitochondria, the Golgi apparatus or the chromosomes themselves that define our genetics. All of this is located in the cytoplasm, which constitutes the neuron’s soma.
Finally, within the neuronal cytoplasm there are also fibrillar proteins, which form the cytoskeleton. This cytoskeleton is what shapes the neuron and provides a mechanism for the transport of molecules.
Another of the parts that make up neurons are dendrites. This name refers to the numerous extensions in the form of small branches that arise from the neuronal body and whose main functions are to receive stimuli and provide 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 their branched shape, along these we find dendritic spines, small spines in which synapses that make the transmission of bioelectric impulses possible.
Finally, the axon constitutes the main prolongation of the neuron (and the largest one). It is responsible for transporting the action potential from the cell body to another neuron.
This long extension arises from the cell body or, in some cases, from a dendrite. Inside we can find the axoplasm, a characteristically viscous substance in which the different organisms of the neurons are found.
One of the main characteristics of these axons is that they can be covered by a layer known as myelin sheath, which can enhance or facilitate the speed with which action potentials or electrical stimuli are transmitted.
Furthermore, neurons can be classified into different types according to the length of the axon: type I and type II Golgi neurons, or according to their shape: pyramidal cells of the cerebral cortex and Purkinje cells.
4. Other neural elements
In addition to the main parts of the neuron described above, there are other particles or sections of great importance for the correct functioning of these. Some of these parts are:
Also known as neurolemocytes, these cells line the axons of the neurons of the peripheral nervous system and are formed by myelin sheaths.
As mentioned above, some axons have a myelin layer that facilitates the transmission of electrical stimuli over long distances.
This concept refers to the tiny spaces found in the myelin sheath and its main purpose is to enhance the speed with which electrical impulses are transmitted.