Frederick Griffith has discovered ______. - Biology (Theory)

Frederick Griffith has discovered transformation.

Explanation:

Frederick Griffith discovered the process of bacterial transformation in 1928 while studying Streptococcus pneumoniae. In his famous experiment, he observed that non-virulent (harmless) bacteria could be “transformed” into virulent (deadly) ones when mixed with heat-killed virulent bacteria. He concluded that a heritable “transforming principle” had been transferred from the dead cells to the living ones, enabling them to gain new physical traits. While Griffith did not identify the substance itself, his work laid the foundation for future scientists to prove that this principle was actually DNA.