in the 50's an American chemist Stanley Miller who subjected a mixture of the supposedly early atmospheric gases (CH4, NH3, H2 and H2O vapor) to an electric discharge. The products that he obtained included several amino acids, fatty acids, and simple sugars. Similar results, using ultraviolet radiation instead of electric discharges demonstrated that solar radiation may have been chiefly responsible for promoting reaction among the gases of the early atmosphere. (to cut to the chase)
As the primitive anaerobic organisms multiplied, the nutrients were depleted and waste products accumulated. Some cells, which then evolved a different means of obtaining food and energy, eventually emerged as the aerobic organism that first accomplished photosynthesis with the aid of chlorophyll. The carbon dioxide accumulated in the atmosphere and oceans by anaerobic and volcanic activity was converted photosynthetically to carbohydrates and gaseous oxygen:
http://www.chem.duke.edu/~bonk/Chem8304/enote1305.html
2006-09-10
08:31:15
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25 answers
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asked by
chris s
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