Re: Atmospheres
There have been many experiments carried out simulating conditions prebiotic Earth. The test atmospheres usually contain mixtures of NH3, CH4, H2, and H2O and a spark generator to simulate lightning. Lots of carboxylic acids, amino acids, nucleic acid bases (like those of DNA, RNA, and ATP), and even pentose and hexose sugars have been observed to form under these conditions. Adding inorganic ions like Cu2+, Ni2+, Zn2+, etc, help to increase the polymerization of these components, not to mention other factors like UV radiation, heat, and things like that. Interesting stuff.
There are molecules that can replace O2, but some organisms on Earth can use H2, H2S, S, HNO3, H2SO4, and CO2 in lieu of O2. But as I've said before, they just don't make enough energy to be useful for anything more than a bacteria, and in that case, it has to have little or no competition!
[ February 20, 2003, 03:28: Message edited by: Captain Kwok ]
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