Miller and Urey’s Experiment

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Miller and Urey’s Experiment: To prove Oparin and Haldane's biochemical theory of the origin of life Miller and Urey in 1952 conducted an experiment. They designed an apparatus containing a glass tube, flask, and gas chamber. They kept NH3, CH4, H2, CO in the gas chamber, and water is boiled in the flask to produce water vapor. The energy was supplied by heating and by electric sparks.


The condenser was used to cool the reaction. They run the experiment for a week. Finally, they analyzed the products formed within the tube. They found different organic compounds like fatty acid, amino acid, sugar, glycerol etc in the tube. Then they proved Oparin and Haldane's theory of the origin of life through a series of chemical reactions among the inorganic gases under the influence of temperature, electric discharges, and cooling.
 
Drawbacks of Urey Miller Experiment
• By examining rocks- dated to be 3.7 billion years old, geologists determined that earth had an oxygenic atmosphere.
• Oxygen is an oxidizing agent and would inhibit chemical evolution.
• Experiment produced a mixture of right-handed & left-handed amino acids, but in nature left-handed ones predominate.
• Now it is thought that the atmosphere of the early earth was not rich in methane and ammonia -essential ingredients in Miller's experiments. 
 

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