The RNA World Hypothesis

I was surprised that Google's price is so much lower than Amazon's though? Less than a half? (Might be locale-dependent, I'm in Poland). It has been long since I bought anything on Google, but I assume it can still be converted to a DRM-free epub like described here?: https://www.reddit.com/r/kindle/comments/3menci/i_prefer_my_...

Where's the catch?

It didn't happen that fast. The earliest direct evidence, (as in: fossils) for life on earth are 3.465 BILLION years old.

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

>Also anyone who’s worked in a lab trying to keep some Lb plates sterile would immediately see how difficult it would be to keep an earth sized Lb plate sterile if the galaxy has a ton of life harboring planets.

The earths diameter is 12742 km.

A petri-dish is usually about 12 cm in diameter.

The closest star system (Alpha Centaury) is 9461000000000 km away (4.35 LY).

So the closest place in the galaxy where there is even sufficient mass for conditions to form life, is ~2970020405 earth-diameters from here.

Two petri dishes on opposite sides of the planet are ~106183333 petri-dish-diameters away from each other.

So purely from a perspective of distance, the chance that two petri-dishes on opposite sides of the planet transmit life between them, is an order of magnitude HIGHER than life coming to earth from outer space.

The difference between a living being with genetic information and a living being without genetic information is the same as between a processor with micro-programmed control and a processor with hard-wired control.

In a processor with micro-programmed control, it is easy to add new instructions or to replace the instructions that it can execute with others having a completely different behavior, just by changing the content of the control memory.

In a processor with hard-wired control, you might be able to change the interconnections between blocks or to replace some logical gates with other kinds of logical gates, but the chances that these changes will result in a new processor that will still function and do something useful are minuscule.

Genetic information is necessary for the evolution of simple self-reproducing living beings to the complex living beings that exist today, but it is not necessary for life, i.e. for growth and reproduction of complex molecules.

It is fortunate that this is true, because otherwise there would have not been any path from inanimate matter to memory molecules like RNA, because they cannot continue to exist without being replicated from the template of an already existing memory molecule, so they cannot have any other function earlier than the first replication begins to produce them, and the replication cannot appear before the monomers, e.g. ATP, are available.

About the RNA synthetase, that is just a catalyst.

It cannot produce any RNA without the monomers (nucleotides) and without energy, i.e. a dehydrating agent like ATP, which must extract the water from the monomers, to condense them in the RNA polymer.

In the first living beings that used ATP and the other nucleotides to perform condensation reactions, the reactions were not controlled as well as today, so there were many parasite reactions that consumed a part of the reactants instead of producing the desirable end products. So some of the ATP molecules must have condensed with themselves and with other nucleotides, instead of producing useful polymers.

From these ATP condensation side-reactions, some kind of RNA synthetase must have been produced by chance and then it began to replicate itself. However that was possible only because ATP and nucleotides produced continuously by the host metabolism were available. Without monomers, the RNA synthetase would not have been able to do anything.