Stanley Miller's Experiment / Harold Upey - Miller's experlment:
In 1953, Stanley Miller under the guidance of his professor Harold Urey conducted an experiment to investigate the conditions under which the simplest organic compounds were formed from the gases of the primitive carth. Miller designed a glass apparatus called "Spark-discharge apparatus" to conduct the experiment: Spark discharge apparatus is roughly rectangular in shape with a Spark discharge chamber, water boiler, U-trap condensers all of which were connected by a rectangular side tube as shown in the diagram. The side tube is connected to the vacuum pump or stop cock, water was takenfg the round bottom flask and the entire apparatus was evacuated to remove the free molecular oxygen. A mixture of gases like methane, hydrogen, and ammonia in the ratio of 2: 1:2 by volume were passed into the apparatus. The water in the round bottom flask was boiled to produce steam which was circulated clockwise in the apparatus. The spark discharge chamber contained two tungsten electrodes which were connected to a sparking coil that produced continuous discharge of sparks which served as sources of energy similar to lighting of the primitive Earth. The convectional current created by the circulation of the steam, carried the gases across the clectrodes. The cooling jacket or condenser present below the sparking chamber, condensed the steam and the contents were collected in the U-trap. When the products were analyzed it was found that there were a number of simpler organic compounds such as amino acids, acetic acid, propionic acid etc. The acids formed were alanine, glycine, aspartic acid, glutamic acids etc. Formation of amino acid is an important step in the origin of life. This Miller's experiment provided the vital proof that organic compounded can be fomed form simple inorganic molecules under the conditions that existed on the primitive earth. This proves the origin of life from chemical substances.
