Difference between revisions of "Miller-Urey experiment"
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[[File:MillerUreyExperiment.PNG|300px|thumb|right|The setup of the Miller-Urey Experiment of 1953. It attempted to simulate primitive Earth gases (Methane, Ammonia, Hydrogen, Water Vapor), primitive oceans (Water), and lightning.]] | [[File:MillerUreyExperiment.PNG|300px|thumb|right|The setup of the Miller-Urey Experiment of 1953. It attempted to simulate primitive Earth gases (Methane, Ammonia, Hydrogen, Water Vapor), primitive oceans (Water), and lightning.]] | ||
In 1953, Stanley Miller reported the production of biomolecules from simple gaseous starting materials using an apparatus constructed to simulate the primordial Earth's atmosphere-ocean system. Miller used what he thought was primitive gases that would be available on a primitive earth: 200 mmHg of CH<sub>4</sub>, 100 mmHg of H<sub>2</sub>, 200 mmHg of NH<sub>3</sub> and 200 ml of H<sub>2</sub>O into the equipment. In other words the ratio was 2:1:2:2 for CH<sub>4</sub>:H<sub>2</sub>:NH<sub>3</sub>:H<sub>2</sub>O. Then he subjected this mixture, under reflux, to an electric discharge simulating lightning for a week while the water was simultaneously heated for that time period.<ref name="exp setup">Parker, E. T., Cleaves, J. H., Burton, A. S., Glavin, D. P., Dworkin, J. P., Zhou, M., Bada, J. L., Fernández, F. M. [https://pmc.ncbi.nlm.nih.gov/articles/PMC4089479/ Conducting Miller-Urey Experiments]. J. Vis. Exp. (83), e51039, doi:10.3791/51039 (2014).</ref> | In 1953, Stanley Miller reported the production of biomolecules from simple gaseous starting materials using an apparatus constructed to simulate the primordial Earth's atmosphere-ocean system. Miller used what he thought was primitive gases that would be available on a primitive earth: 200 mmHg of CH<sub>4</sub>, 100 mmHg of H<sub>2</sub>, 200 mmHg of NH<sub>3</sub> and 200 ml of H<sub>2</sub>O into the equipment. In other words the ratio was 2:1:2:2 for CH<sub>4</sub>:H<sub>2</sub>:NH<sub>3</sub>:H<sub>2</sub>O. Then he subjected this mixture, under reflux, to an electric discharge simulating lightning for a week while the water was simultaneously heated for that time period.<ref name="exp setup">Parker, E. T., Cleaves, J. H., Burton, A. S., Glavin, D. P., Dworkin, J. P., Zhou, M., Bada, J. L., Fernández, F. M. [https://pmc.ncbi.nlm.nih.gov/articles/PMC4089479/ Conducting Miller-Urey Experiments]. J. Vis. Exp. (83), e51039, doi:10.3791/51039 (2014).</ref> | ||
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| + | ===Results=== | ||
| + | In his original paper, Miller was able to identify glycine, α-alanine and β-alanine while Aspartic acid and α-aminobutyric acid were less certain.<ref name="Miller1953">Stanley Miller. 1953. "[https://web.archive.org/web/20120317062622/http://www.abenteuer-universum.de/pdf/miller_1953.pdf Production of Amino Acids Under Possible Primitive Earth Conditions]". Science. 117 (3046): 528–9.</ref> Miller also stated "it is estimated that the total yield of amino acids was in the milligram range" which means that very little even material formed after a week of continuous running of the experiment non-stop.<ref name="Miller1953" /> | ||
==See also== | ==See also== | ||
*[[Origin of life]] | *[[Origin of life]] | ||
Revision as of 18:43, August 29, 2025
The Miller-Urey experiment was the first attempt to reverse-engineer the conditions in earth's atmosphere that produced abiogenesis – the production of life from non-life. By recent analysis, the experiment did produce as rich a mixture of amino acids as life would require. But it produced those acids in a racemic mixture, and even secular scientists are not willing to accept this as the definitive proof of how life began.
The 1953 experiment
In 1953, Stanley Miller reported the production of biomolecules from simple gaseous starting materials using an apparatus constructed to simulate the primordial Earth's atmosphere-ocean system. Miller used what he thought was primitive gases that would be available on a primitive earth: 200 mmHg of CH4, 100 mmHg of H2, 200 mmHg of NH3 and 200 ml of H2O into the equipment. In other words the ratio was 2:1:2:2 for CH4:H2:NH3:H2O. Then he subjected this mixture, under reflux, to an electric discharge simulating lightning for a week while the water was simultaneously heated for that time period.[1]
Results
In his original paper, Miller was able to identify glycine, α-alanine and β-alanine while Aspartic acid and α-aminobutyric acid were less certain.[2] Miller also stated "it is estimated that the total yield of amino acids was in the milligram range" which means that very little even material formed after a week of continuous running of the experiment non-stop.[2]
See also
References
- ↑ Parker, E. T., Cleaves, J. H., Burton, A. S., Glavin, D. P., Dworkin, J. P., Zhou, M., Bada, J. L., Fernández, F. M. Conducting Miller-Urey Experiments. J. Vis. Exp. (83), e51039, doi:10.3791/51039 (2014).
- ↑ 2.0 2.1 Stanley Miller. 1953. "Production of Amino Acids Under Possible Primitive Earth Conditions". Science. 117 (3046): 528–9.