Origem da Vida: Descrição Da Primeira Química para Leigos


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What drives the molecules to be ordered by themselves? is there an ordering force? How do yo know that first molecules that got some level of order, kip that order during millions of years? I can tell a story of how the Mona Lisa painted alone without human intervention, will you believe that tale? No? why no?, I can not believe in your tale
To Jorge Juarez: I believe you may not understand how chemistry works. I will try to explain in layman’s terms.
RNA/DNA did not just form by themselves. At first, there were extremely simple replicating molecules. How this works is that when these molecules come into contact with certain chemicals, they bind. Certain molecules will bind to certain parts of the molecule. Some of these happen to be a “reverse” copy; they bind in the opposite order.
When all spots have been filled, the new molecule splits at these sites, and thus replicates. It splits do to opposite forces. These first molecules were only 5-6 atoms in length; very simple. Because these molecules could replicate, they eventually became very common, and thus were everywhere.
Now, it is common knowledge that molecules can undergo changes (chemical reactions). Sometimes, these changes would make these molecules replicate faster by becoming more attractive (more binding spots). Sometimes they would become more stable (harder to break). Etc. Now, because these changes would make these molecule “superior” (they were able to replicate better than previous versions), they would become very numerous. And just like before, after time they would become extremely common.
Now, this process would repeat, and repeat, and repeat. Each time getting just SOMEWHAT slightly more complex. Repeat this process millions of times, and its not hard to see where DNA came from. The reason the molecules kept that order is because once they started replicating, there were tons of them. So even if most got destroyed, there were always extra because they replicated. What you have to also understand is that there are TRILLIONS AND TRILLIONS of different chemical combinations possible.
Even infinite. So it is not unlikely that at LEAST one of these combinations could produce a self-replicating molecule. Also, there are 10000000… molecules in the Earths oceans, undergoing chemical reactions. So its not really hard for life to form.
The analogy of the Mona Lisa does not work, because dna did not just fully appear. It took millions of small very simple steps in order to finally emerge. The process took millions-billions of years.
+Jorge Juarez  – Because we do not know the exact conditions of early Earth. That is why we are unable to replicate it. That is the whole point; we are trying to find the conditions of early Earth. We have an idea, but its too long ago to know exactly. Thus, scientists are trying different methods and environments. We are slowly narrowing it down. The key is replicating the EXACT same conditions. Given that this was 4 BILLION YEARS AGO, I think a lot of credit is due to the fact we ALREADY have RNA forming in labs. This I think is your misunderstanding. We DO know how life formed. We DO know the process. What we don’t know is the environment.

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