Deuxième chose, on est tous au courant que les théories actuelles sur l'abiogenèse se sont tournées vers les molécules d'ARN réplicateur comme précurseur de la vie au lieu des protéines.
Il est important de noter, pour votre éducation, que de telles molécules n'existent pas à l'état libre dans la nature. Pauvre vous, je viens de vous donner un choc en vous enlevant vos illusions.
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"In today's organisms, nearly all chemical reactions are catalyzed by proteins, powerful enzymes that have evolved to master a bewildering array of tasks. However, proteins cannot carry a cell's genetic information. That deed is the domain of the nucleic acids: double-stranded DNA and its single-stranded relative, RNA. Although DNA is more widely known, scientists have found that RNA is far more complex and versatile.
Modern proteins and nucleic acids need each other to exist and function. ****However, it is extremely unlikely that these two complex types of molecules evolved together on the young earth.**** Within the last decade, biologists have turned to RNA as a way out of this chicken-and-egg paradox. In addition to acting as a genetic librarian and stenographer, RNA can mimic proteins by triggering certain reactions. But until now, that class of reactions had seemed limited."
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