At cell organelles are structures found in the cell's cytoplasm that function as small organs, performing the most varied functions. An example of an organelle is the mitochondria: elongated spherical structure that is about 10 µm in length and is related to the production of energy for the cell.
→ Structure of a mitochondrion
Mitochondria are cell organelles that are distinguished by the presence of two membranes, one outer and one inner, which are separated by the intermembranous space. The innermost membrane protrudes into the organelle, forming the so-called mitochondrial crests. These ridges increase the inner surface of the organelle and have components that ensure the performance of the cellular respiration. In addition, the ridges delimit the mitochondrial matrix, which is formed by water, ions, enzymes and other substances.
Mitochondria are organelles capable of auto-duplicate and have own DNA, which appears as double and circular filaments and is very similar to that of bacteria. These organelles also have
RNA (messenger, ribosomal and transporter) and ribosomes small. It is worth noting that the mitochondrial genome encodes some important proteins, however, most proteins are encoded by genes located in the cell nucleus.→ What is the function of mitochondria?
Mitochondria are related to the production of energy for the cell, a process known as cellular respiration. In these organelles, there are some steps of this important process, which guarantees the oxidation of organic molecules and the production of ATP (adenosine triphosphate) molecules.
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→ Where are mitochondria found most?
Mitochondria are organelles normally found in places in the cytoplasm where energy expenditure is intense. An example of this can be seen in spermatozoa, gametes with great locomotion capacity due to the presence of flagella. In these cells, the greatest amount of mitochondria is in the middle part, which guarantees energy for locomotion.
Some tissues have a greater amount of mitochondria when compared to others. This is the case of the cells of the muscle tissue cardiac striatum, which is rich in these organelles because of its constant need for energy.
→ Mitochondria and endosymbiosis
It is believed that mitochondria arose in cells, like chloroplasts, through a process of endosymbiosis. This means that mitochondria were probably formerly a prokaryote organism, which was engulfed and started to live in symbiosis with the cell that phagocytosed it. This theory is supported by the fact that mitochondria they have a double membrane, DNA and ribosomes of their own, circular DNA similar to the chromosomes of bacteria and are capable of self-duplicating.
By Ma. Vanessa dos Santos
Would you like to reference this text in a school or academic work? Look:
SANTOS, Vanessa Sardinha dos. "What is mitochondria?"; Brazil School. Available in: https://brasilescola.uol.com.br/o-que-e/biologia/o-que-e-mitocondria.htm. Accessed on June 27, 2021.
