How did life originate?

Answer

Dear Thomas,

How life originated is not yet known!

We do know that organic molecules can ‘form’ such as amino acids (the building blocks of proteins) and nucleotides (the building blocks of DNA) in the atmosphere (the composition of what is called the ‘primordial soup’) and in specific circumstances (temperature, lightning strikes). and RNA). These small building blocks could also bind together to form precursor biomolecules, which already have an onset of bioactivity (enzymes that speed up reactions). However, for real ‘life’ you need (at least) a cell (like our cells or those of bacteria and other micro-organisms). Viruses (the smallest structures we count among living things) also do not have a cell of their own, but that is precisely why they infect our cells or those of plants, animals or microorganisms. They cannot live without a cell. By life we ​​mean: (1) the maintenance (maintenance, repair when necessary) of the existing structure (virus particle, cell or complete organism with all the trimmings) by (2) consuming energy from the environment and new biomolecules (3) reproduce and (4) slowly evolve into an increasingly successful life form.

To put together a cell, you need a whole lot of biomolecules together (this could still be done in the primordial soup), but separated from that primordial soup by a bio-membrane. And that’s exactly where the shoe pinches. Making a membrane like the one around our cells is not easy. It is not yet known how this was possible. A primitive membrane consists of 2 layers of phospho- and glycolipids in a special structure, closed all around, with an aqueous solution inside and outside. The lipids themselves do not dissolve in water, but float in a monolayer on top. Once a primitive membrane has been made, proteins still need to be in it to let in food molecules and to take out waste products, because a membrane without proteins is completely closed and impermeable.

If you could do this, you are well on your way to creating ‘life’, from there one has an idea of ​​how evolution worked.