Soma neuronal or pericarion: parts and functions
Neurons are one of the most important cell types in our body , since they allow the transmission of information between its different parts through the nervous system. Through them, a series of bioelectrical impulses are generated and transmitted that allow us to perform each of the actions we carry out, both voluntarily and involuntarily, and whether we refer to physical behaviors or cognitive processes. or emotional
But neurons are not homogeneous masses: if we focus on their structure we can distinguish different elements or parts. One of the most important is the soma of the neuron, or pericarion , to which this article is dedicated.
- Related article: "Types of neurons: characteristics and functions"
The central part of the neuron: The soma or pericarion
It is known as soma or pericarion the central and most important element of the cell, in which is the nucleus and from which its other parts are derived, as extensions of the first: dendrites and axon. The shape of the soma, as well as its position in relation to the rest of its components of the same neuron, can vary greatly depending on the type of neuron we are talking about (although it is usually rounded and large).
The somas of neurons make up what we call gray matter , linked to the processing of nervous information. In fact, different brain structures of great importance are mainly formed by gray matter, such as the cortex itself, the basal ganglia, the thalamus or the hypothalamus.
- Maybe you're interested: "Gray matter of the brain: structure and functions"
Main parts of the neuronal soma
Within the soma or pericarion we can find a large number of elements, all of them of great importance, which participate in the proper functioning of the cell and its maintenance. The main ones among them are the following.
The main and most important element of the soma is the nucleus, in which there are the genetic instructions that govern the formation, growth, functioning and death of the neuron, that is, the DNA. Around or around the nucleus can be found the nucleolus, which generates the transcription of RNA that will end up generating the ribosomes present in the cell.
- Related article: "Differences between DNA and RNA"
The cytoplasm is the liquid medium in which the nucleus and the rest of the elements of the soma are located, actively participating in the cellular metabolism and the facilitation of its movement . The membrane of the neuron is limited by the cytoskeleton.
This element formed by different types of filaments and tubules they contribute to providing structure and form to the pericarion and also participate in the migration and movement of the different components of the soma.
4. Nissl bodies
Rough endoplasmic reticulum clusters present mainly in the soma (although they can also be observed in the dendrites) and which contain a large number of ribosomes, which are involved in the creation of proteins and neurotransmitters. In addition, they are a fundamental part of the pericarion, because if the cell is damaged (not only in the soma but also for example in the axon) these elements will contribute to its regeneration, dissolving and sacrificing to maintain the functioning of the neuron (in a process known as chromatolysis).
5. Golgi apparatus
Element of great importance for the functioning of the neuron, the Golgi apparatus is a large organelle in which the proteins generated by Nissl bodies are temporarily stored , incorporating other elements in such a way that they can be packaged in macromolecules sent through the neuron to the nerve terminals.
6. Smooth endoplasmic reticulum
Lattice of interconnected tubules whose main function is serve as assembly point of many substances secreted by the other elements . It also participates in the synthesis of lipids and elements related to the neuron membrane. The aforementioned Golgi apparatus is, in fact, smooth endoplasmic reticulum.
Set of elements present in the cytoplasm whose main function is that of Degrade the intracellular material , facilitating the operation of the soma by eliminating harmful remains.
Present in some of the previous structures but also freely localizable in the cytoplasm, ribosomes are macromolecules formed by ribosomal RNA and some proteins which are responsible for the synthesis of proteins. Technically they are the elements that carry out the expression of the genetic information present in the nucleus, through this synthesis.
Fundamental elements of the cell whose main function is that of give it energy and keep it alive , carrying out cellular respiration and synthesizing ATP (element used by cells as fuel).
The soma or pericarion plays a fundamental role: it is about the part of the neuron that governs the functioning and keeps alive this biological unit , being the nucleus of the cell (in which are the genetic instructions present in the DNA) in him. It is responsible for producing and maintaining a sufficient level of energy so that the cell can continue to function. It also contains elements that make up the cell's cytoskeleton, as well as some elements that repair it from possible damage, such as Nissl's bodies.
Perhaps the most important role of the soma is the fact that in it the synthesis of most of the proteins found in the neuron is carried out, and among them those that are going to be part or they will start the synthesis of most neurotransmitters .
Finally, it is from it that the extensions that are going to receive and send the nervous information are derived.
It is the part of the neuron that, likewise, allows the processing of nervous information and its reaction to it , being the somas of the neurons important part when explaining how the human being works and governs their behavior.
- Kandel, E.R .; Schwartz, J.H. & Jessell, T.M. (2001). Principles of neuroscience. Fourth edition. McGraw-Hill Interamericana. Madrid.
- Ramón y Cajal, S. (2007). Histology of the nervous system of man and vertebrates. Volume i. Ministry of Health. Madrid.