Question

Describe the Miller and Urey experiment on the origin of life.

Answer 1

The oparin-Haldane concept of the biochemical basis of the origin of life was put to a test by Stanley Miller and Harold C.Urey (1953) in the laboratory by creating the probable conditions of primitive earth. They designed their apparatus of glass tubes and flasks as shown in the figure and created an atmosphere containing hydrogen, ammonia, methane and water vapour in one chamber of the apparatus and allowed condensed liquids to accumulate in another chamber. The energy was supplied by heating the liquid containing chamber as well as by electric sparks from electrodes in the gaseous chamber.

The experiment was run continuously for a week and then they analysed the chemical composition of the liquid inside the apparatus. They found that the liquid contained a large number of complex organic compounds including some amino acids such as glycine, adenine and aspartic acid. However, from the result of their experiment, they suggested that the electrical discharges produced during lightening in the primitive atmosphere of earth containing hydrogen, ammonia, nitrogen, water vapour might have resulted in the formation of amino acids and other essential building blocks. Thus, the experiment of Miller and Urey provides support for the biochemical concept of origin of life of Oparin and Haldane.