GENERAL KNOWLEDGE

Detailed explanation-1: -Answer. Answer: Alexander Fleming noticed that bacteria growing on a plate of agar did not grow next to a mold that was growing on the same plate. He wrote in his laboratory report: “The mold may be producing a substance that kills bacteria.” This statement is described as: An observation.

Detailed explanation-2: -Fleming added nutrient broth that had not had mold growing on it to another dish of bacteria. The bacteria in this dish were not killed. Fleming concluded that the mold produced a bacteria-killing substance in the broth. He called the substance that killed the bacteria penicillin.

Detailed explanation-3: -Fleming believed that a chemical produced by the penicillin was causing the bacteria surrounding it to die. 2. What was the hypothesis? If the bacteria in the petri dishes died, then the penicillin in the petri dish produced a deadly chemical.

Detailed explanation-4: -One day in 1928 he discovered that bacteria he had been growing on a culture plate had been killed in an area close to where a mould was accidentally growing. He isolated the mould and showed that it released a substance that inhibited bacterial growth. He named the substance penicillin after the name of the mould.