Cellular respiration (internal respiration or aerobic respiration) refers to all metabolic processes by which energy is obtained in cells. Molecular oxygen serves as the oxidant in this process. This is reduced and in this way water is formed from oxygen and hydrogen.
What is cellular respiration?
Cellular respiration refers to all metabolic processes by which energy is obtained in cells. To supply energy, cells take up glucose (dextrose). The glucose is subsequently broken down to water or carbon dioxide in the mitochondria or cytoplasm. In this way, the cells obtain the compound adenosine triphosphate (ATP), a universal energy source that is extremely important for many metabolic processes. Overall, cellular respiration is divided into three steps:
- Glycolysis: Here, one molecule of glucose is broken down into two molecules of acetic acid. From each molecule of glucose, two C3 molecules are obtained, which are transported to the mitochondria, where the next degradation step occurs.
- Citrate cycle: the activated acetic acid enters the citrate cycle and is degraded in several steps. In the process, hydrogen is released, which is bound to so-called hydrogen transport molecules. As a by-product, CO2 is formed, which is then released by the cell and excreted via respiration.
- The final oxidation is also called the respiratory chain, where the hydrogen obtained is burned to water and ATP is produced.
Through this stepwise process, a very large amount of energy can be used. A total of 36 ATP molecules are obtained from one molecule of glucose, which corresponds to an efficiency of over 40 percent.
Function and task
Every cell in the body has a nucleus, where genetic information is found. The cell is separated from the outside world by the cell membrane. This consists of tunnel proteins, glycoproteins, cholesterol, lecithin, and fatty acids. An intact cell membrane is very important because, for example, the disposal of waste products or nutrition depends on it. The plant fatty acids in the cell membrane also improve the exchange of substances. An excess of cholesterol or animal fat and protein causes the membranes and the cell structure as well as the boundary layers between the different tissues to solidify. This makes the exchange of substances more difficult and only an insufficient amount of oxygen and nutrients is brought to the cells. Inside the cells are the mitochondria, which have their own genetic information and can also multiply. Body heat and body energy are obtained in the membranes of the mitochondria. If the energy production is disturbed, diseases such as cancer can occur. Oxygen atoms or hydrogen ions can enter the cells via the air we breathe or the food chain. Due to different oxidation and reduction processes of oxygen and hydrogen, energy production takes place. Electrons are brought to a low energy level with the help of co-enzymes, releasing energy. With the help of this energy, protons can be pumped from inside the mitochondria into their intermembrane space and then flow back inside. This creates ATP (adenosine triphosphate), a molecule that plays a central role in storing body heat and body energy. Adenosine triphosphate can be described as the center of energy metabolism. Thus, a cell has over one billion ATP molecules, which are hydrolyzed or phosphorylated thousands of times a day. The energy that is released in this process is needed for various metabolic reactions. If there is a destruction of the co-enzymes within the respiratory chain, the energy production breaks down and an acidic environment occurs. Consequently, the mitochondria leave the cell or may die and there is a stagnation of energy production, i.e. insufficient heat production takes place. This is evident, for example, in the run-up to cancer, as a lower body temperature can be detected in cancer patients.
Diseases and ailments
Our body has an unimaginably large number of cells in which energy is produced. The exchange of energy, substances as well as information takes place via the cell membrane.Due to environmental toxins, proteins, animal fats, free radicals and acids, normal nutrient and oxygen supply is prevented, moreover, the toxins cannot be properly disposed of. As a further consequence, the energy production of the cells is disturbed and the genetic information is damaged, which can lead to numerous diseases. Due to wrong nutrition, cigarette consumption, heavy metals, overacidification, mental stress or chronic diseases, free radicals are increasingly formed. These damage the body structures and lead to premature aging. Free radicals are molecules that have either one electron too few or too many. Therefore, they try to bring about a balance by very radically snatching electrons from other molecules. As a result, a chain reaction occurs in which molecules are destroyed or damaged. Very often, free radicals are so-called oxygen radicals, which trigger an oxidation process and destroy fats or enzymes. In addition, free radicals cause mutations in the mitochondrial or cell nucleus DNA and damage the connective tissue. They cause numerous chronic diseases such as high blood pressure, immune deficiency, Alzheimer’s disease, Parkinson’s disease, allergies, diabetes, rheumatism or arteriosclerosis. As waste products are deposited, the transport of nutrients between cells and blood vessels is impeded, because the free radicals cross-link sugar proteins, proteins and all basic substances. This creates an environment for pathogens and the immune defense is favored. Since the body cannot cope with an excess of radicals, it needs help in the form of enzymes, Q10, a wide variety of vitamins or selenium, which render the free radicals harmless and protect the body.
