What is the dissimilation?Dissimilation takes place in the cells of the human body.
The term "dissimilation" derives from the Latin term 'dissimilis' (= dissimilar) or 'dissimilatio' (= dissimilarity). The dissimilation is based on the enzymatic degradation of the body's own substances, which are first absorbed through the diet. These include, for example, fats and carbohydrates as well as glucose.
Subsequent to their degradation, there is an excretion of the now present alien substances in the form of water and carbon (dioxide). Furthermore, during the entire dissimilation large amounts of energy are gained, which store and process the cells in the form of the universal energy carrier adenosine triphosphate (ATP).
Per molecule of glucose, the number of ATP molecules obtained amounts to 38. There is also a differentiation between oxidative energy gain (= reaction sequence with oxygen), also called aerobic respiration, and anaerobic respiration (= without influence of oxygen). Last is known in daily usage mainly as fermentation.
Function & Task
Dissimilation takes place in the cells of the human body. It includes the four steps glycolysis, oxidative decarboxylation, citrate cycle and the final respiratory chain, also called endoxidation.
Apart from glycolysis, which takes place in the cytoplasm, all other partial processes take place in the mitochondria or at their inner membrane. Mitochondria are small cell organelles that are surrounded by a double membrane and thus isolated from the cytoplasm. When human beings consume glucose via food, an energy-use phase begins, in which a phosphate group attaches to the sixth carbon atom of the glucose molecule. This originates from a previous cleavage of a molecule ATP into ADP (= adenosine diphosphate). After the same process is repeated, the glucose with its six carbon atoms breaks down into two molecules of three carbon atoms each.
The energy release phase then begins. The phosphates dissociate from the carbon atoms and combine with ADP to form ATP. Water molecules are split off and there is a high-energy reduction of the substance NAD to NADH + H +. The latter products are called "reduction equivalents" and serve to transfer and store electrons.
This is followed by oxidative decarboxylation. Here, too, a comparable reduction takes place first; however, the original glucose molecule subsequently combines with a coenzyme to enter the citrate cycle.
Fats first pass through the fatty acid cycle before being introduced into the citrate cycle at an appropriate point. Here the molecule goes through a series of different, new compounds and splits of atoms. All of these processes primarily contribute to providing enough additional electron carriers for the end oxidation and to dispose of the human toxic carbon dioxide.
At the inner mitochondrial membrane and in the gap between the inner and outer membrane (= intermembrane space), the reduction equivalents reach and oxidize. As a result, electrons are trapped on the inner membrane through various protein complexes and hydrogen protons are simultaneously pumped into the interspace. These combine with oxygen atoms and leave the cell as a water molecule.
The respiratory chain is, in energetic terms, the most important part of the total dissimilation. Due to the trained forces and concentration differences between the inner and outer milieu of the mitochondrion, 34 molecules of ATP are formed.
Diseases & complaints
In order for such a high number of ATPs to develop, sufficient oxygen must be available. However, under anaerobic conditions, ie fermentation, this is missing so that the endoxidation can not occur. This in turn means that with the same energy supply only a ten percent energy production takes place, since ultimately only four of the actual 38 molecules ATP can be recovered.
Such (lactic acid) fermentation occurs, for example, during sports or comparable physical stress. This is notable for the painful burning of the muscles, as they are acidified by the excess and not completely degraded products.
Permanently disturbed energy production, which results from the lack of appropriate coenzyme, insufficient oxygen supply from the outside, or intake of pollutant-rich water, can lead to cancer in the case of hardship. Such a disorder can be detected early on the basis of the reduced body temperature of those affected. The release of heat is ultimately associated with the production of energy.
But even less drastic complaints can be the result of a short-term reduced oxygen supply to the cells. Thus, a deficiency in the cells of the brain leads to difficulty concentrating and tiredness. At the same time, the deficiency in the heart, lungs and arteries can cause extreme fatigue and circulatory problems, including collapse.
In addition, the entire immune system is weakened by the lack of oxygen in the cells, so that an increased susceptibility to all diseases must be assumed.
Likewise, the central nervous system consists of dissimilation-driving cells, the neurons. Since these also do not work correctly and possibly acidify in case of incomplete dissimilation, the nervous system becomes over-excitable. This manifests itself in the form of nervousness, irritability to muscle tremors and muscle pain. Also, stress and overstimulation can be the cause of a disturbed dissimilation.
In order to counteract a chronic disturbance of dissimilation in the entire organism, it is advisable to ensure a healthy, balanced diet and sufficient exercise, ideally in the fresh air. It is also important to avoid unnecessary physical and mental stress.