Alexander Fleming was a biologist and pharmacologist by trade, but his most famous discovery was accidental and changed medicine forever. Which substance did he identify and isolate?
Alexander Fleming discovered penicillin after carelessly leaving a culture plate out in his lab before going on holiday. He came back to find that mold had grown - the mold that would end up being the world's first true antibiotic.
Asked by Kiera Hart · Last updated 1 year ago · 439K views