Final answer:
Beadle and Tatum conducted experiments on the red bread mold Neurospora crassa to prove the "one gene-one enzyme" hypothesis, demonstrating the direct relationship between specific genes and the production of enzymes.
Step-by-step explanation:
George Beadle and Edward Tatum conducted their groundbreaking experiments on the organism Neurospora crassa, a type of red bread mold. Their work was seminal, demonstrating the relationship between genes and the proteins they encode, and ultimately leading to the proposition of the "one gene-one enzyme" hypothesis. Beadle and Tatum exposed N. crassa to X-rays to induce mutations and then observed growth in different media to determine specific biochemical pathways affected by these mutations. By systematically testing mutants that could not grow on minimal media, they were able to conclude each gene was responsible for producing a specific enzyme necessary for the biosynthesis of vitamins and amino acids, essential for the mold's growth.
Their experiment is not just a hallmark in genetics but also an exemplar of methodical scientific investigation, revealing the direct link between genetic heredity and enzyme production. This influential concept has evolved into the broader understanding that genes often code for proteins, which may be enzymes or structural components of cells. Beadle and Tatum's research from the 1940s has profoundly shaped our understanding of molecular biology and genetics.