1. abiotic synthesis of small organic molecules, such as A.A's and nitrogenous bases.
2. joining of these small molecules into macromolecules, such as proteins and nucleic acids.
3. packaging of these molecules into protocells, droplets with membranes that maintained an internal chem different from that of their surroundings.
4. origin of self-replicating molecules that eventually made inheritance possible.
Synthesis of Organic compounds on Early Earth
Solar Syst formed about 4.6 bya. Collions of huge chunks of rock and ice left over from formation of S.S generated enough heat to vaporize available water, preventing seas from forming. Ended 4.2-3.9 bya.
As earth cooled, water vapor condensed into oceans, H2 escaped into space.
Organic compounds could of formed from simpler molecules. energy for this organic synth could of come from lightning and intense UV rad.
early oceans were a sol of organic molecules, soup from which life arouse.
perhaps first organic compounds formed near volcanoes or deep-sea vents, where hot water and minerals gush into the ocean from earth's interior.
The atmosphere of early Earth
Early earth probably had an atmosphere made mainly from nitrogen and hydrogen gas and very little oxygen gas
One theory holds that the atmosphere contained clouds of H2S, NH3 and CH4 creating a reducing environment. From this environment, the formation of carbon based molecules tat we associate with life required little energy to form.
second source of organic molecules
meteorites. metorites that land on earth are carbonaceous chondrites, rocks that are 1-2%C. A meteroite that landed in Austrailia in 1969 contained more than 80 amino acids. It contained other keyo rganic molecules, including lipids, simple sugars, and nitrogenous bases such as uracil.