so in the begining there were gases and stuff like hydrogn. overtime cuz of gravity they came together and made new stuff like oxygen. but all these were non living gases so how did things like FUBA or Ameba come from
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So for starters let’s go back in time, around 3.8 billion years ago. Keep in mind what I am about to say hasn’t been experimentally proven but we will get to that soon enough.
At the 3.8 bya mark, things were weird. Earth wasn’t the beautiful paradise we live in. It had:
1. tiny bits of oxygen, O2
[the stuff we breathe]
2. Whole lot of Carbon dioxide, CO2
[the stuff plants use to photosythesise]
3. Whole lot of Nitrogen, N2
[The stuff that’s most of our present-day air content]
4. Little bits of–
Hydrogen (H2)
Hydrogen sulphide (H2S)
[that rotten egg smell]
Carbon Monoxide(CO)
[Incomplete burning of stuff like coal can release these, extremely deadly]
Now these are the basic gases that were there.
Now there was of course a hell lot of sunlight and lightning. (Energy sources)
So we have the gases and a source of energy!!
These combined and created organic molecules!! This is a huge deal as till here it’s been proven experimentally by Stanley Miller.
The next part comes in making these molecules grow and grow a hell lot. So here’s the tricky part. We need these molecules to combine and be macromolecules which is fine and dandy.
But they have to replicate themselves!
There is nucleic acid (stuff like your DNA) which does replicate on its own with a template strand (it’s like one strand of your DNA just makes a photocopy of itself)
But at that time DNA wasn’t the first nucleic acid. It was in reality RNA!
So now we have an unstable mutating nucleic acid that just desperately wants to divide and replicate.
So what is hypothesised is that it probably got wrapped in a phospholipid membrane and created a CELL.
(Imagine a filling wrap, where the filling is an RNA and it gets wrapped by Phospholipid)
What’s a phospholipid? It’s what makes up our cell membrane! It looks like a mutated sperm with a head (phosphate) and 2 tails (2 fatty acids)
RNA is like the ancestor of DNA in a sense. This RNA could replicate a ton and mutate a lot too cause it was way too reactive.
The reason why we have DNA for modern species is because it is a hell lot more stable and not unstable like RNA.
Cells divide because of the RNA. Metabolism arises.
What is metabolism? It’s like your food breaking down to give you strength!
Now remember that RNA is hella mutative and mutates rapidly.
Some work out for the cell to survive, and some don’t.
This trial and error keeps happening.
Slowly…like really really slowly they shift into prokaryotes.
What are prokaryotes? Simply put they are the older versions of our cells, with every organ in them just floating around without any membrane or anything in the cell.
Now some prokaryotes like photosynthesis! Like our nowadays plants they can make food too!!
The nucleic acid keeps mutating more and more.
Then we reach something like amoeba and stuff that you mentioned in the question.
Evolution happens, and organisms keep getting created! Complexity and body design become way more difficult to adapt to the harsh and ever-changing environment.
And hence life as we know today is formed.
To be noted that to date no cell has been created by recreating the early earth atmosphere.
I know it’s oversimplified and I skipped a lot of nuances but anyone please be free to add on and say where I might have gone wrong.
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