What groundbreaking experiment did Stanley Miller conduct in 1953?

Stanley Miller's groundbreaking experiment in 1953 focused on organic compound synthesis, specifically the creation of amino acids under conditions similar to those thought to exist on early Earth. This experiment is significant because it provided evidence that simple organic compounds necessary for life could be formed from inorganic precursors through natural processes.

Miller and his colleague Harold Urey simulated the conditions of the early Earth by using a closed system filled with water, methane, ammonia, and hydrogen, then subjected it to electrical sparks to mimic lightning. After a week, they found that several amino acids, which are the building blocks of proteins, had been formed. This experiment supported the theory of abiogenesis, which posits that life could arise from non-living matter.

The implications of this experiment extend to our understanding of the origins of life on Earth and beyond, stimulating research into how life might form on other planets and the potential for prebiotic chemistry in extraterrestrial environments. Thus, organic compound synthesis stands as the correct answer, reflecting Miller's significant contribution to biological and chemical science.