Origin of Life

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Scientists say when asteroids showered on earth they were the ones who brought water to earth which started life. But how did few molecules of water started life on earth?
 

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  • #2
.Scott
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Nobody knows.
It's called abiogenesis.
Here is a link to the wiki page: https://en.wikipedia.org/wiki/Abiogenesis

One presumed step in the process is the creation of organic molecules from inorganic materials: rocks, water, and gases.

Perhaps the real trick is to go from there to an organic molecule (or system) that can self-replicate and mutate in any natural prebiotic environment. I don't believe anyone has discovered that trick.
 
  • #4
Pythagorean
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  • #5
Drakkith
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Scientists say when asteroids showered on earth they were the ones who brought water to earth which started life. But how did few molecules of water started life on earth?
They didn't bring a "few" molecules, they brought more than 1018 metric tons. The reason this is important to life is because water forms a medium in which an enormous range of chemicals can mix together, which in turn allows thousands of different chemical reactions to occur. In addition, water's polar properties (meaning one side of it is charged negative and the other side is positive) cause the folding of certain molecules we call proteins and provides a mechanism for the construction of cell membranes. All of these things are requirements for all known life.
 
  • #6
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I wish to offer speculations that

1) the first cells had no lipid membranes, but only proteinaceous walls vaguely like the outer layers of prokaryotes and viruses... This hypothesis affords you the option of getting started with only RNA and protein.

2) TRNA. Binds amino acids. On to the rybose opposite the nucleobase [2a]. This suggests that an early RNA strand could have used ribose as the translator intermediate with all of the nucleobases on one side of the backbone, templating for all of the amino acids on the other. Indeed [2b], only the pyrimidines U,C have known prebiotic precursors. So possibly the first RNA strands were purely Pyramidine based. And so had no self binding. Or double Helix forming structural. Capabilities. A pure pyrimidine RNA strand would remain single stranded And linear, an ideal template for amino acid. Linkage.

[2a] https://www.atdbio.com/img/articles/protein-synthesis-tRNA-large.png
[2b] http://astrobiology.com/2018/12/life-has-a-new-ingredient.html
 
  • #7
pinball1970
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Scientists say when asteroids showered on earth they were the ones who brought water to earth which started life. But how did few molecules of water started life on earth?
As well as water 1000s of organics in the form of meteorites fall to earth every year, some of these organics contain amino acids alcohols and bases already formed

This one fell 1969 and has been studied intensively since, the fragments when collect weighed over 100kg

https://en.wikipedia.org/wiki/Murchison_meteorite

I would google deep sea vents as a starting point for first proto cells

https://www.livescience.com/26173-hydrothermal-vent-life-origins.html
 

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