Kitobni o'qish: «Life is one of the forms of existence of matter»
The problem of the origin of life, as a worldview problem, is of paramount philosophical importance. Theologians prove the improbability of a purely accidental origin of life. They deny or simply do not accept the effect of adaptation that occurs in primary systems due to their interaction with the external environment, as something to which any rationality is completely alien, can give rise to a rational organization of the living. Theologians believe that scientists are trying to find the source of a natural development in matter itself, while this process is only the implementation of a program once compiled by the Creator. However, for materialists, the ways of the evolutionary development of matter that led to the emergence of primary living beings on our planet are mostly clear. Schematically, it can be divided into several stages: firstly, the occurrence of hydrocarbons, cyanides and their closest derivatives in outer space and during the formation of the Earth as a planet; secondly, abiogenic, independent of life, syntheses of increasingly complex organic substances in interplanetary space and on planets, the emergence of a "primary broth" on the Earth's surface – an aqueous solution of various and complex organic substances; thirdly, the self-formation in this "broth" of individual multimolecular systems capable of interacting with the environment and on the and, finally, the further evolution of these formations, their comprehensive improvement on the basis of prebiological selection, the emergence and development of primary organisms. Further research on the problem of the origin of life is devoted to a detailed study of each of these stages, but the transition from purely chemical to biological evolution is now attracting special attention of scientists.
Important for its development was the discovery in the 50s of the fact that the basis of living matter is formed along with proteins by deoxyribonucleic and ribonucleic acids (DNA and RNA). Now this theory, based on the achievements of biochemistry, biophysics, molecular biology, cytology and other sciences, leads to the conclusion that life on Earth appeared about 4 billion years ago. years ago. The evolution of carbonaceous compounds originally present on Earth and the multimolecular systems formed from them led to the emergence of life. Experiments simulating conditions on the surface of the young Earth showed that then a variety of more complex compounds were formed from simple organic compounds, water, and ammonia, including amino acids, nucleotides, which in turn formed protein- and nuclein-like polymers – polypeptides and polynucleotides. In a solution of organic substances, in the sun-warmed water of the seas, under certain conditions, multimolecular colloidal systems (coacervate droplets) were formed, separated from the environment, but maintaining a constant exchange of matter and energy with this environment. Inside the coacervate droplets, or some other phase-separated formations, the interaction of polynucleotides and polypeptides took place: polynucleotides served as matrices for non-enzyme synthesis of polypeptides, polyaminoacids bound certain nucleotides. This interaction had a direct impact on the stability of the formations. Those in which the mutual structural and functional conditionality of polynucleotides and polypeptides was more pronounced than in others, turned out to be more stable and durable, since they were better balanced with the environment. There was a primary selection of formations with the most mutually "fitted" in structural and functional relations polypeptide and polynucleotide elements. Under these conditions, such formations appeared, within which nucleotide elements turned into nucleic acids that acted as organizers and matrices of protein synthesis, and polypeptide elements – into protein enzymes that ensure the self-replication of nucleic acid molecules. These formations could increase the level of orderliness of their structure through the use of energy and matter of the external environment, reproduce themselves on the basis of information contained in the chemical structure of nucleic acids, and had an individually different ability to balance with the environment, so that primary selection turned into a qualitatively new, biological phenomenon – natural selection. Such formations were the primary living bodies.
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