Meaning of Mitochondria
What is Mitochondria:
The mitochondrion is a cellular organelle found in eukaryotic cells, and provides the energy necessary to carry out cellular activity.
In other words, the mitochondria are responsible for breaking down nutrients and synthesizing adenosine triphosphate or ATP, which is essential for obtaining cellular energy.
The mitochondrion is characterized by being large, compared to other cellular organelles, and having a globular shape. Its main function is to supply the electron carriers (ATP), a product of cellular respiration, which provide the energy that the cell needs.
Likewise, the mitochondria has the ability to reproduce by itself, this is because it has its own DNA, which allows it to form more mitochondria depending on the cell's need to have a greater amount of ATP. Therefore, the more active cells are, the more mitochondria you need.
The mitochondria obtain ATP when it performs cellular respiration, in this process it takes certain molecules from food in the form of carbohydrates that, when combined with oxygen, produce ATP.
Parts of the mitochondrion
The mitochondria has a plasma structure and a dynamic character that allows it to vary in size and shape, since it can divide, fuse or deform.
However, it is customary to represent elongated. Its size is estimated to be between 0.5 and 1 µm in diameter and approximately 7 µm long.
The outer membrane works as protection, is permeable to various molecules, smooth and has porins, which are proteins in the form of pores, through which larger molecules can pass. Hence, this membrane is composed of a good percentage of proteins.
The inner membrane is composed of a high percentage of proteins and lipids. Furthermore, it is extensive and allows it to form folds known as "mitochondrial chalk".
It does not have pores, so it is less permeable, and only allows the passage of small cells, however, it does have a significant number of aqueous ducts that allow the transit of molecules.
Various chemical reactions of importance to the cell occur in the mitochondrial crest, such as cellular respiration, electron transport, oxidative phosphorylation, and protein transport.
This ridge forms a membranous system that connects with the inner membrane of the mitochondria, in various parts, to facilitate the transport of metabolites, organic compounds, to various parts of the mitochondria.
The intermembrane space is located between the outer membrane and the inner membrane, which is composed of a liquid similar to hyaloplasm, in which a significant number of protons are concentrated, generated by the pumping of enzyme complexes.
Hence, in this space there are enzymes that allow the transfer of energy from ATP to other nucleotides.
The mitochondrial matrix is composed of a jelly-like fluid. It contains water, ions, its own ribosomes that synthesize proteins, mitochondrial RNA molecules, metabolites, a high amount of enzymes, as well as ATP and ADP substances.
Also, it has double-stranded DNA molecules that perform mitochondrial protein synthesis.
In the mitochondrial matrix, different metabolic routes important for life are carried out, such as the Krebs cycle, in which the nutrients that serve to generate energy are metabolized by the mitochondria, and the beta-oxidation of fatty acids.
Function of the mitochondria
Below are the important functions performed by the mitochondria.
The energy production represented in ATP molecules is the most important function of the mitochondria. This energy is obtained through cellular respiration, a process that involves three stages in the mitochondria, being them: the oxidation of pyruvate, the Krebs or citric acid cycle and oxidative phosphorylation.
Heat production can be generated from exercise-associated thermogenesis, non-shivering thermogenesis, which occurs in the matrix of the mitochondria, and diet-induced thermogenesis.
It is the process of programmed and controlled cell death. Apoptosis is important in multicellular organisms since it controls the growth of cells, and for the development of organisms and tissues.
Mitochondria serve to store calcium ions, which is very important for cell biochemistry. Mitochondria regulate the amounts of necessary for muscle contraction and the release of neurotransmitters, and is vitally important for bone health.
Mitochondrial DNA is duplicated and its copies are transmitted through female gametes, that is, from the mother. Hence, some scientists consider that the mitochondria is part of the consequences of sexual preproduction.