Which of the following statements regarding antibiotics is not correct ?
(i) Antibiotics are the attenuated microorganisms which in small concentration can kill or retard the growth of other harmful microorganisms.
(ii) Penicillin was the first antibiotic discovered by Alexander Fleming (1928) while working on bacterium Staphylococcus aureus.
(iii) The full potential of penicillin as an effective antibiotic was established by Ernest chain and Howard Florey.
(iv) Fleming, Chain and Florey were awarded the Nobel Prize in 1945

Options

A. (i) only
B. (ii) only
C. (ii) and (iv)
D. (i),(ii) and (v)

Answer

To determine which statement regarding antibiotics is not correct, we will analyze each statement one by one.

1. **Statement (i)**: "Antibiotics are the attenuated microorganisms which in small concentration can kill or retard the growth of other harmful microorganisms."
- **Analysis**: This statement is incorrect. Antibiotics are not attenuated microorganisms; they are chemical substances produced by microorganisms (like bacteria and fungi) that can kill or inhibit the growth of other harmful microorganisms. Attenuated microorganisms are those that have been weakened and are often used in vaccines, not as antibiotics.

2. **Statement (ii)**: "Penicillin was the first antibiotic discovered by Alexander Fleming (1928) while working on bacterium Staphylococcus aureus."
- **Analysis**: This statement is correct. Alexander Fleming discovered penicillin in 1928 while he was studying Staphylococcus aureus. This discovery marked the beginning of antibiotic therapy.

3. **Statement (iii)**: "The full potential of penicillin as an effective antibiotic was established by Ernest Chain and Howard Florey."
- **Analysis**: This statement is also correct. Although Fleming discovered penicillin, it was Chain and Florey who developed it into a usable form and demonstrated its full potential during the 1940s.

4. **Statement (iv)**: "Fleming, Chain and Florey were awarded the Nobel Prize in 1945."
- **Analysis**: This statement is correct as well. Fleming, Chain, and Florey were awarded the Nobel Prize in Physiology or Medicine in 1945 for their contributions to the discovery and development of penicillin.

**Conclusion**: The statement that is not correct is **(i)**: "Antibiotics are the attenuated microorganisms which in small concentration can kill or retard the growth of other harmful microorganisms."