Explanation

Chemical theory of origin of life is the most accepted theory. Stanley Miller in 1953, who was than a graduate student of Harold Urey (1893-1981) at the university of Chicago, demonstrated it clearly that ultra-violet radiation or electric discharges can produce complex organic compounds from mixture of $CH_{4},\ NH_{3},\ H_{2}O\$and$\ H_{2}$. The ratio of methane, ammonia and hydrogen in Miller’s experiment was 2 : 1 : 2 Experimental Evidences of Chemical Evolution Experi ik mentally chemical theory of evolution performed by SL Miller and HC Uray in 1953. He created electric discharge in a closed flask containing $CH_{4},H_{2},NH_{3}$ and water vapour at 800 C. He observed formation of amino acids. In similar experiments other the observed, formation of sugar, nitrogen bases, pigments and fats [image:7_image18.png] The first non-cellular forms of life could have originated-3 billion years back. The first cellular form of life did not possibly originated till about 2 billion years ago because the conditions were non-biogenic at that time. This version of biogenesis, i.e., the first form of life arose slowly through evolutionary forces from non-living molecule was accepted by majority