In nature, there are several ways to nourish the body. They depend on the structural features, development and living conditions of the body. Chemosynthesis is one of them. For which organisms is it characteristic and in what conditions is it possible? These and other questions will be answered by our article.
Autotrophic organisms
The two main ways of feeding organisms are hetero- and autotrophic. At the first, the assimilation of ready-made nutrients occurs: proteins, lipids and carbohydrates. This is how animals, mushrooms, and some bacteria feed. Autotrophs are able to independently synthesize organic matter from inorganic in the presence of certain conditions. This group of organisms includes plants and a special group of bacteria.
Types of autotrophic nutrition are photosynthesis and chemosynthesis. Their main difference lies in the source of energy for life. Chemosynthesis is a nutritional method in which oxidation of inorganic compounds occurs. Not all living organisms can carry out this process .
Hemotrophs
The process of chemosynthesis, discovered in 1887 by the famous Russian scientist S.N. Vinogradov, is characteristic of a special group of unicellular prokaryotes. These include iron, sulfur, and nitrifying bacteria. All of them oxidize the corresponding inorganic substances. So, as a result of a chemical oxidation reaction, iron is converted from two to trivalent. And hydrogen sulfide - into a simple substance, i.e. sulfur. Nitrifying bacteria are of particular importance in nature.
During the decomposition and decay of organics, ammonia is released. A group of nitrifying bacteria oxidizes this substance to nitric acid. When dissolved in water, this substance forms soluble salts. As a result, plants, absorbing them from the soil, are enriched with nitrogen, the presence of which is a necessary condition for the development of the root system. Thus, chemosynthesis is a process that provides the necessary substances to different groups of organisms at the same time.
Phototrophs
Another group of autotrophic organisms are plants. They use sunlight to produce organic matter. Therefore, the method of their nutrition is also called phototrophic. This process is possible only in special cell organelles - chloroplasts. They contain a coloring matter - the pigment chlorophyll.
It is he who stains the photosynthetic parts of autotrophic organisms in green. Also a necessary condition for this process to occur is the presence of water and carbon dioxide, which is released as a result of breathing of living organisms. The process of photosynthesis is of great planetary importance. The fact is that as a result of its course, not only glucose carbohydrate is formed, which is used by phototrophs as a source of energy, but also oxygen. And without this gas, the process of breathing is impossible, and therefore life itself.
The difference between chemosynthesis and photosynthesis
Despite the fact that the two above processes are varieties of the autotrophic method of nutrition, they also have a number of significant differences.
Photosynthesis is impossible without light. In addition, it occurs only in the presence of chloroplasts in the cells. Chemosynthesis is a process that occurs without these conditions, but only in bacterial cells.
They differ in their biological value. Phototrophs provide all life with oxygen. Bacteria carry out the cycle of nitrogen, sulfur and other substances.
Another important difference is the result that autotrophic organisms receive directly for themselves. Photosynthetic plants form glucose carbohydrate. When combined, the molecules of this substance create the polysaccharide starch. It is a reserve plant nutrient. Chemotrophs do not synthesize organic matter directly, but through ATP molecules - adenosine triphosphoric acid. This substance is a kind of accumulator of energy in the cells of living organisms. If necessary, it splits. This process proceeds in several stages, in each of which a certain amount of energy is released. Chemotrophs use it to carry out vital processes.
So, photosynthesis and chemosynthesis are varieties of the autotrophic way of feeding living organisms, which themselves produce the energy necessary for the processes of their growth and development.