Stanley L. Miller and Harold C. Urey’s Experimental Support for Oparin’s Chemical Evolution Theory:
Apparatus and Procedure:
Miller and Urey devised a spark-discharge apparatus, a glass chamber, to experimentally validate Oparin’s chemical evolution theory. The apparatus was sterilized, evacuated, and filled with methane, ammonia, and hydrogen gases in a 1:2:2 ratio. A tube introduced water vapor, and an electric discharge simulated lightning. Heating and condensation were used to replicate evaporation and precipitation.
Observation:
The liquid in the U-tube, subjected to continuous electric discharge for several days, exhibited a brown color.
Results and Conclusions:
Chemical analysis of the brown liquid revealed the presence of simple organic compounds, including urea, amino acids, and lactic acid. This experiment strongly supports the idea that the basic molecules in Earth’s early atmosphere combined to create the organic foundations of life.