The basic mechanism by which energy production is provided in the living body operates through the organelle called “mitochondria deki in our cells. The energy provided by the mitochondria to the living body is used by other organelles in different pathways. Thus, the basic and first examples of energy transformations in our bodies are observed in our cells.
Mitochondria, with their unique genetic material and double-membrane tissue, can only be carried by eukaryotic organisms. Representation of mitochondria in eukaryotes that exclude backs and bacteria in the tree of life and which form the basis of our energy, and enzymes that provide energy production in organisms that do not carry membrane organelles. Well; how is the energy we need at every point from vital metabolic activities to our daily lives? What kind of pathways work effectively in our body to ensure energy production?
At this point, we need to make a distinction between living things that contain mitochondria, which are our power plants, and living things that do not. Organisms possessing mitochondrial cells can carry out their own activities using the chemical energy produced in this organelle. In organisms that do not carry mitochondria, a different process operates, but these organisms also use essentially the same chemical energy, although their sources are different. This chemical energy is called ATP. Adenosine Tri Phosphate in ATP expansion; It consists of adenine nucleic base and phosphate molecules.
ATP production overview: Respiratory mechanism
Breathing is the main mechanism that produces energy in the living body. Respiration may be carried out by means of oxygen; oxygen-free. Therefore, energy production in the body is not dependent on the presence of oxygen. In mitochondria, this situation is slightly different. Mitochondria are basically organelles where oxygen breathing occurs. As the amount of energy produced by oxygen respiration is higher, it can be stated that mitochondria are the power plants of our body as in the basic judgment. At this point, let’s broaden our basic question and answer this question: How does our body produce energy?
At this point, the primary focus should be on the respiratory mechanism. When breathing occurs in a living thing, the nutrients consumed and digested by the living thing are converted to energy by various mechanisms. These mechanisms occur within the cell. This energy, which is synthesized in all cells in the living body, cannot be stored but can be spent by converting it into other energies.
Respiration basically occurs in two different ways. These differences are the differences in the use of oxygen as previously mentioned. Aerobic respiration (oxygen breathing) and anaerobic respiration (oxygen-free breathing) differ depending on whether or not oxygen is used in their mechanisms. Let’s take oxygen-free breathing first and then focus on mitochondria and energy production there. Oxygen-free respiration occurs on the basis of the operation of the lik Glycolysis ”pathway in the cytoplasm. Usually “Glycolysis izler is followed by ayrı Ethyl Alcohol Fermentation” and akt Lactic Acid Fermentation reaksiyon reactions. The starting material of Glycolysis is Glucose, which can be summarized by the destruction of Glucose up to Pyruvic acid. Glycolysis, which is the most basic pathway of respiration, is observed in all living things and the enzymes necessary for Glycolysis are the same in all living things. The fact that the general functioning of enzymes and pathways is exactly the same in all living things is also important from an evolutionary point of view.
ATP production through metabolic events is called “Phosphorylation ve and this concept is divided into several titles. The main form of phosphorylation observed during the glycolysis phase is Fos Phosphorylation at Substrate Level ancak, but in Aerobic Respiration, where energy production is widely observed, “Oxidative Phosphorylation” is the basic energy production mechanism.
Mitochondria in office: Aeobic Respiration and Oxidative Phosphorylation
Let’s open the curtain we open with glycolysis and enter the oxygenated respiration. This type of respiration follows Glycolysis, the Krebs cycle and the ETS pathway. The location of Krebs and ETS mechanisms is the mitochondria, which are the main power plants of our cells. At this point, it should be noted that the answer to our main question in mitochondria!
Mitochondria play a role in the production of metabolic energy in eukaryotic cells; It is responsible for the production of ATP through oxidative phosphorylation, and this organelle carries a specific genome and proteins synthesized by these genomes. The mitochondria contain internal and external mitochondrial membranes. The inner membrane has a plurality of curved structures extending towards the interior of the organelle. These curved structures are called “krista..
The matrix, which is the liquid region where the inner membrane of the mitochondria separates from the outer area, carries the mitochondria genome and the essential elements for the realization of oxidative phosphorylation. Pyruvic acid, which continues its path for Aeorobic respiration after the occurrence of glycolysis, is transported to the mitochondria through various channels. Here, an introduction to the Krebs Cycle is observed; Pyruvate is converted to Acetyl CoA with the presence of CO2. With the production of this substance is passed to the Krebs cycle. The Krebs Cycle, also known as the Citric Acid Cycle, is the central pathway in which oxidative degradation occurs for both carbohydrates and fatty acids.
The Krebs Era starting with the presence of acetyl CoA; This results in the reduction of NAD + and FAD coenzymes to NADH and FADH2. Here, Fos Phosphorylation at Substrate Level ”is observed. NADH and FADH2 formed by the Citric Acid Cycle are transferred to the ETS pathway, the center of merkezi Oxidative Phosphorylation için for the next step. Here, high-energy electrons from NADH and FADH2 are transferred to molecular oxygen through a series of carriers on the membrane surface. Here, the energy produced through the membrane is converted into potential energy and used for ATP production. At this point, it should be noted that the inner mitochondrial membrane is also the main site in the ETS pathway following Krebs. At this point, “krista mal folds are of great importance. In addition, the inner mitochondrial membrane contains a number of proteins that are the precursors for the transport of pyruvic acid and fatty acids. Otherwise, the inner mitochondrial membrane is not susceptible to passage against small molecules with such substances and even ions. This is a critical feature necessary to maintain the proton gradient that causes oxidative phosphorylation. However, unlike the inner mitochondrial membrane, the outer mitochondrial membrane is highly permeable. The basis of this situation is the presence of a number of channels that allow diffusion of small molecules and protein channels that allow the passage of large molecules.
ATP production is carried out by the use of Oxygen in the path called Electron Transport System. In this respect, this pathway is where Oxidative Phosphorylation takes place. A large amount of the energy produced in Aerobic Respiration is generated at this stage.
Visualization of human mitochondrial DNA
Mitochondria contain a separate genetic system outside the cell’s own genome. This situation; It is explained by the theory known as the os Endosymbiotic Theory ve, which states that the mitochondrial organelle originates from a living bacterium by establishing a symbiotic relationship with that cell in a larger cell. This theory is confirmed by the striking similarities observed by comparing the sequences of the mitochondria genome with the aforementioned Rickettsia prowazekii bacteria. Mitochondrial genomes have a circular structure, very similar to the genome structure of bacteria.
The genetic material of mitochondria is inherited from the mother. From this perspective, the main lineage of a living thing can be traced through mitochondria. In this way, the line can be drawn to reach the first female individual of the species. However, recent studies have revealed certain exceptions. According to these exceptions, genetic information transmitted from the father can be found in the mitochondrial genome.