Read the following statements regarding antibiotics.
I. Antibiotics are chemical substances produced by certain microorganisms that can inhibit or kill other disease-causing microorganisms.
II. Penicillin was the first antibiotic to be discovered, and its discovery was a chance discovery.
III. The role of penicillin as an antibiotic was confirmed by Ernest Chain and Howard Florey.
Which of the statements given above are correct?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → I, II and III
True. I. Antibiotics are chemical substances produced by certain microorganisms that can inhibit or kill other disease-causing microorganisms. This is the book’s meaning of an antibiotic: a substance made by microbes that kills or slows the growth of disease-causing microbes.
True. II. Penicillin was the first antibiotic to be discovered, and its discovery was a chance discovery. Fleming saw by chance that a mould on an unwashed culture plate stopped Staphylococci from growing. It made penicillin, the first antibiotic.
True. III. The role of penicillin as an antibiotic was confirmed by Ernest Chain and Howard Florey. Fleming found penicillin, but its full potential as an antibiotic was established later by Chain and Florey. All three won the Nobel Prize in 1945.
All three statements are correct.
NCERT Extract:
Antibiotics – “… Antibiotics are chemical substances, which are produced by some microbes and can kill or retard the growth of other (disease-causing) microbes. You are familiar with the commonly used antibiotic Penicillin. … Alexander Fleming while working on Staphylococci bacteria, once observed a mould growing in one of his unwashed culture plates around which Staphylococci could not grow. He found out that it was due to a chemical produced by the mould and he named it Penicillin after the mould Penicillium notatum. However, its full potential as an effective antibiotic was established much later by Ernest Chain and Howard Florey.”