In this article we are going to define what cell metabolism is, what are its parts, functions and how it helps cells and living beings in the cycle of life.
This biological mechanism consists of different steps and consists of an elaborate process that can be difficult to understand. Therefore, we are going to explain in a simple way the fundamentals of this concept.
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What is cellular metabolism?
The concept of metabolism comes from the Greek, and means “change of quality”. At biological levels, we refer to chemical, physical and physiological changes in the structure and function of cells .
Without these changes, life as we know it today would be unfeasible, so we can say with total certainty that cellular metabolism allows life as such to be created (and destroyed).
Cellular metabolism in evolution
It would be expected that depending on the species, the environment and the needs faced by a living being throughout its evolution, the characteristics and cellular metabolic processes would vary. But the truth is that no.
The basic metabolic pathways of all species are known to be the same , even between species as different as a single-celled bacterium and an elephant. This is probably explained by the fact that these routes appeared at the beginning of evolution as basic mechanisms and were very useful for the development of the species.
What is a metabolic
pathway A metabolic pathway is a succession of chemical processes that occur until a final product is reached. Thus, we would be talking about chain processes where A results in B, thanks to a metabolic process; to later obtain C through B, by a new metabolic process. And so on.
What is cellular metabolism for?
Broadly speaking, cellular metabolism, as we have said, allows the life and evolution of a species, both at the ontogenetic and phylogenetic levels.
In fact, we can say that cellular metabolism affects so many functions that it is difficult to enumerate them, since it is an intrinsic part of terrestrial biology. Anyway, mainly this biological mechanism serves so that cells can grow, reproduce, survive, respond to the environment and do the activities for which they serve .
Phases of cellular metabolism
Broadly speaking, we can divide cellular metabolism into two phases that we will explain below:
By definition,all catabolic processes are responsible for releasing energy . So that we understand each other, we will use the example of sugar.
When we ingest sugar (or almost any substance) different cellular metabolic processes allow this sugar to be converted into energy for the body (this particular process is called glycolysis).
In this way we can say that catabolism is the part of cellular metabolism that allows the human body (and that of all living beings) to obtain energy from other chemical compounds .
As might be expected, the anabolic phase of cellular metabolism is responsible for, making use of the energy available in the body, synthesizing chemical compounds useful to the body.
This is why the famous anabolics are chemical compounds that allow the generation of new useful elements for the muscles of athletes, thus improving their performance.
Enzymes and cellular metabolism
To understand cellular metabolism we must keep enzymes in mind. Likewise, we have to take into account that in any metabolic process, there are two components. The first is the substrate and the second the product.
The substrate is the chemical compound that the body has before the process in question, while the product, as its name indicates, is what is obtained thanks to the process.
There are almost as many enzymes as there are substrate-reaction processes in the body., and these are in charge of intermediating, making it possible for the process to be much faster and more efficient, or even making it possible.
These enzymes are regulated by the body through different physiological processes that, depending on the conditions in which the body is found, increase or decrease their quantity, so that the cellular metabolism adapts to the needs of the organism as a whole.
What molecules do we metabolize?
There is a wide variety of molecules that serve in cellular metabolic processes for the phases of anabolism and catabolism. Anyway, next, we are going to see the most important ones.
Proteins are made up of amino acidsand organized in chain form by peptide bonds (an amino group plus a carboxyl group).
The enzymes we were talking about are a type of protein that is used for all kinds of metabolic processes. Other proteins, however, are responsible for giving “structure” to the cells of the body, as if they were a skeleton.
This is why the molecular metabolism of proteins can have a wide variety of functions, being these catabolized or anabolized.
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At the cellular level, carbohydrates serve to store energy or as structural components . Its catabolization offers a large amount of energy to the body.
Like carbohydrates, lipids are a great source of energy for the body . They are molecules that stand out for their great biodiversity. They make up a large part of the cell membrane of the cells of the organism.
Toxicity and metabolism
An interesting point that we discovered through understanding what cell metabolism is is its implication in the levels of toxicity of an organism.
Especially in the catabolism part,the characteristic cellular metabolism of a species is what dictates which foods are beneficial for it and which are not.
This is because those foods that can be processed (catabolized) through the different metabolic processes to obtain energy and other useful compounds, will be non-toxic foods. On the other hand, those foods that cannot be catabolized will be useless foods for the body or even toxic, if it does not have the necessary mechanisms to get rid of them.
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