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Impudence!: The Most Significant Of The Scientific Theories

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The theories of the origin of life they try to explain how living things originated. How life arose as we know it is a question that many philosophers, theologians and scientists have asked themselves for many years, in fact, we could say that almost since man has been a man. Different scientific records establish that the earth was formed about 4.

Although there are no fossil records or older geological evidence, many scientists agree that other life forms may have existed earlier, but that fossils may have been destroyed by heat and the shape changes of many rocks during the Precambrian. What happened during the almost 2 billion years that elapsed since the origin of the earth and the visit web page of the first fossils? It is the biological events that occurred at that time that made the emergence of life possible and those that are so much debated in the scientific community today. Some scientists propose that the "initial" earth was impacted by different types of celestial objects and that the temperatures on this planet were so high that the water was not in a liquid state, but in the form The Most Significant Of The Scientific Theories gas.

However, many agree that Precambrian land may have had temperatures similar to land today, meaning that water could be found in liquid form, condensed into oceans, seas, and lakes. The Earth's atmosphere at the time, on the other hand, is thought to be strongly reducing with zero or very little free oxygenso that after exposure to different forms of energy the first organic compounds could have been formed.

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From the Greeks to many scientists of the mid-nineteenth century, the proposal was accepted that living things could arise spontaneously, without other parental organisms, from "non-living" matter. Therefore, for many centuries, different thinkers were convinced that insects, worms, frogs and other vermin formed spontaneously on mud or on decomposing matter.

These theories were discredited on more than one occasion by the experiments carried out by Francesco Redi and Louis Pasteurfor example.

Redi proved that unless adult insects laid their eggs on a piece of meat, the larvae did not spontaneously emerge on it. On the other hand, Pasteur later showed that microorganisms could only come from pre-existing microorganisms.

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Furthermore, it must be said that this theory was also ignored because in different historical contexts "spontaneous generation" referred to two quite different concepts, namely:. Thus, the theory of spontaneous generation disappeared from the scene and the scientific community began to wonder how those "simpler unicellular beings" emerged that evolutionists spoke of. Inthe scientists A. Oparin and J. Both researchers suggested that the "initial" earth must have had a reducing atmosphere poor in oxygen, in which all molecules tended to donate electronsa condition that could perfectly explain some events:.

Ina scientist named August Arrhenius proposed that "life-bearing seeds" were scattered throughout cosmic space and that they fell on the planets and "germinated" when conditions there were favorable. This theory, also known as The Most Significant Of The Scientific Theories theory of panspermia from the Greek breadwhich means "everything" and spermThe Most Significant Of The Scientific Theories means "seed"was supported by different scientists and we can also find it referred to in some texts as "the extraterrestrial origin of life".

Later, part of the scientific community hinted that the origin of life proposed by Oparin and Haldane could have started on earth thanks to an electrical "spark" that provided the energy necessary for the "organization" of the fundamental organic compounds from of inorganic compounds a form of abiogenesis. Through their experiments, both scientists demonstrated that, from inorganic substances and under some special atmospheric conditions, an electrical discharge was capable of 31 Unit organic molecules such as amino acids and carbohydrates. This theory proposed, then, that with the passage of time the more complex molecules that today characterize living beings could have been formed; which is why this was so supportive of Oparin and Haldane's "primeval stock" theories a few years earlier.

Another theory, perhaps a little less known and accepted, proposes that life arose in deep ocean waters, the surface of which was presumably covered by a thick and thick layer of ice, since the Sun of the initial earth probably did not affect so strongly. The theory proposes that the ice could have protected whatever the biological phenomenon occurred in the sea, allowing the interaction of the different compounds that originated the first living forms.

After it could be demonstrated in a laboratory that organic compounds such as amino acids could form from inorganic matter under certain conditions, scientists began to wonder how the polymerization process of organic compounds occurred. Let's remember that cells are made up of large and complex types of polymers: proteins polymers of amino acidscarbohydrates polymers of sugarsnucleic acids polymers of nitrogenous basesetc. Inthe biochemist Sidney Fox and his work group discovered that, under experimental conditions, if a set of amino acids was heated in the absence of water, they could join together to form a polymer, that is, a protein.

These findings served for Fox to suggest that in Thwories "primitive broth" proposed by Oparin and Haldane, amino acids could have been formed that, read article they came into contact with a hot surface, promoting the evaporation of water, could form proteins. Organic chemist Alexander Cairns-Smith Philosophy Government proposed that the first molecules that Scirntific life possible could be found on clay surfaces, which not only helped to concentrate them, but also promoted their organization into defined patterns.

Therefore, it was suggested that other important elements, such as metabolic networks and membrane formation, for example, be added later to the "primeval" system. Tye the reactivity characteristics of RNA, many scientists support the notion that the first auto-catalytic structures were formed by this nucleic acid evident as ribozymeshypotheses known as "the world of RNA". Accordingly, RNA could potentially have catalyzed the reactions that allowed its own copying, making it capable of transmitting genetic information from generation to generation and even evolving.

On the other hand, different researchers rather supported The Most Significant Of The Scientific Theories notion that life took place first in "protein-like" organic molecules, establishing that the initial life forms could have consisted of "self-sustaining" metabolic networks prior to nucleic acids.]