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The emergence of the first organisms
When in the world are having such proteinaceous materials, began a new stage in the development of matter - the transition from organic compounds to living beings. First organic substances were in the seas and oceans in the form of solutions. They did not have any structure, any structure. However, when solutions of proteins or other similar organic compounds are mixed together, the solutions are distinguished from special semisolid, gelatinous formation - coacervates. For example, if clear solutions are mixed ovalbumin and gelatin, they fouled and microscopically distinguishable in their floating in the water droplets are small sharply defined. This is the coacervates. They are all concentrated in a solution of protein substances.
Although coacervate droplets of liquid, but they have some internal structure. The particles of substance which are not arranged randomly, both in solution and with certain regularity. In the formation of coacervates arise rudiments of organization, however, is still very primitive and unstable. For the most droplets that organization is important. Any coacervate droplet of solution able to detect in which floats, or another substance. They are chemically attached to the substance of most of the droplet. Thus it is the process of creation, growth. But in any droplet along with Origination observed decay. One or another of these processes, depending upon a
composition and internal structure of the droplets is faster and begins to dominate.
Let us imagine that at some point the primary ocean mixed solution proteinaceous materials formed coacervate droplets. They do not float in clean water and in a solution of various substances. Droplets caught these substances and grow at their expense.
The growth rate of individual droplets varies. It depends on the internal structure of each of them.
If the droplet is dominated by the processes of decomposition, it soon disintegrates. Substance, its components go into solution and absorbed by other droplets. More or less long-term there will be only those droplets in which the processes of creation prevail over the processes of decay.
Thus, all arising accidentally, so to say "bad" forms of organizing themselves falling out of the process of further evolution of matter.
Each individual droplet can not grow indefinitely as a solid mass - it breaks up into droplets subsidiaries. But every drop at the same time something different from their "sisters" and separated from the others, growing and changing yourself. The new generation of poorly organized droplets all die, decompose, and the most advanced participate in the further evolution of matter. So in the process of life is a kind of natural selection coacervate droplets. Coacervates growth gradually accelerated. Number of organized matter on the surface of the Earth has increased, complicated by his organization.
Ultimately improvement coacervates led to a new form of existence of matter - to the emergence of the simplest in the world of living beings.
Hydrocarbons to proteins
Age of the Earth is determined by science in different ways within 5 billion years , life on it there are more than 2 billion years . Thus, the greatest period of its existence, our planet was lifeless. A simple hydrocarbons and organic matter arising from them, began to appear on the earth's surface from the beginning of its formation . They served as the initial link of the long chain of transformations , which eventually led to the emergence on the earth's surface, its water shell and in the atmosphere of a large number of diverse and sometimes very complex substances . In the very nature of hydrocarbons already incorporated the possibility of such transformations (see Vol 3 DE , Art. "Organic matter around us"). But in order for them to happen , you need an adequate supply of energy from the outside. Such energy on the earth's surface was available in several forms: the radiant energy of the sun , particularly ultraviolet light , electrical discharges in the atmosphere , the energy of atomic decay of natural radioactive substances.
The possibility of complex organic compounds in those conditions , which were on the surface of the Earth in the early periods of its existence , we can prove even direct laboratory experiments . Recently, the American researcher S. Miller artificially reproduced primary environment of Earth's atmosphere , he missed a silent electric discharge through a mixture of methane, hydrogen , ammonia and water vapor. The result is a amino acids - the main components of the protein molecule. Indian scientist K. Bahadur in a similar experiment was amino sunlight . This experience through the use of ultraviolet rays significantly refined our scientists at the Institute of Biochemistry . Bakh USSR Academy of Sciences . Japanese scientist experiments Sh Akabori also showed how the conditions in the primary periods of the Earth's existence
The possibility of complex organic compounds in those conditions , which were on the surface of the Earth in the early periods of its existence , we can prove even direct laboratory experiments . Recently, the American researcher S. Miller artificially reproduced primary environment of Earth's atmosphere , he missed a silent electric discharge through a mixture of methane, hydrogen , ammonia and water vapor. The result is a amino acids - the main components of the protein molecule. Indian scientist K. Bahadur in a similar experiment was amino sunlight . This experience through the use of ultraviolet rays significantly refined our scientists at the Institute of Biochemistry . Bakh USSR Academy of Sciences . Japanese scientist experiments Sh Akabori also showed how the conditions in the primary periods of the Earth's existence
History of hydrocarbons
At the beginning of this century, many naturalists deny the possibility of the formation of organic compounds from inorganic matter . It was believed then that the inorganic forms of carbon compounds (eg , carbon dioxide, air ) are converted in vivo into organic exclusively by means of living beings. This opinion has been formed because it is so formed is currently the overwhelming mass of organic substances. Green plants absorb carbon dioxide from the air and create a water and organic substances they need for life and growth. Herbivores get these substances by eating plants , and predators - eating herbivores . Thus, the entire living world now uses organic substances formed with the participation of living beings.
Scientists, astronomers have found however, that all celestial bodies have hydrocarbons. But many of them have no life . Therefore , there arose independently hydrocarbons from living organisms. One would think that hydrocarbons and on our planet could be formed before the appearance of living organisms. Geologists are sometimes deeply buried rocks , in cracks granites hydrocarbon gases , and even traces of liquid hydrocarbons. These gases and liquids may appear there is any connection with the living beings .
History of the Earth shows that the formation of our planet, and the first period of its existence on the surface of the globe appeared enormous amount of simple organic substances.
Now astronomy is generally accepted that the Earth and other planets in the solar system formed from a giant cloud of gas and dust matter . Such gas- dust matter is in interstellar space now. Astronomers have learned to determine its composition. It is found methane ( CH4) . Possibly there are more complex hydrocarbons. When particles of gas and dust clouds merged into the larger planets ( Jupiter, Saturn ) , methane and other gases preserved in the primitive atmosphere of evolving planets. There astronomers detect these gases now. And in the composition of the Earth - it is in fact a relatively small planet - carbon was only in the form of graphite and carbides ( carbon compounds with metals ) . Of carbides when they interact with water to produce hydrocarbons , and entered into the earth and water - in the form of hydrates of different rocks . Consequently, hydrocarbons and their simple derivatives were bound to be formed on Earth long before her living beings.
Cell precursors - coacervate droplets
Coacervate droplets and surrounding fluid ( aqueous solution) called coacervate systems (" koatser - vare " in Latin - raking in a pile ) . In such droplets gather molecule substances.
Nowadays there are more than 250 different chemical composition of droplets. They can be artificially synthesized from the compounds resembling proteins , carbohydrates , nucleic acids , etc. , as well as compounds within the cytoplasm. Especially droplets easily arise from molecules with different charges of the molecules such as proteins , charged positively , and nucleic acid negatively charged . Droplets with nucleic acids in the ultraviolet microscope appear red. In view pasted as interference microscopes droplets become colored . With visible light rays in the interference microscope can weigh up to 10-14 each droplet of light rays passing through the droplet bent differently because the droplets have a different weight . As the droplets can flow from the fast chemical reaction catalysts , such as enzymes. Coacervate droplet size of from 0.5 to 640 microns, and as many cells. Our scientists at Moscow State University showed that the coacervate droplets have the same weight and water content , as well as cells . This predkletochnye structure.
Further improvement has led them in due time to the emergence probiontov - predecessors of modern organisms .