Which one of the following is not true about antibiotics

Options

A. First antibiotic was discovered by Alexander Fleming.
B. The term 'antibiotic' was coined by S. Waksman in 1942.
C. Some persons can be allergic to a par- ticular antibiotic.
D. Each antibiotic is effective only against one particular kind of germ.

Answer

To determine which statement is not true about antibiotics, let's analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Antibiotics**:
- Antibiotics are antimicrobial substances that act against bacteria. They are produced by microorganisms and can help prevent or treat bacterial infections.

2. **Evaluating the Statements**:
- **Statement A**: "The first antibiotic was discovered by Alexander Fleming."
- This statement is true. Alexander Fleming discovered penicillin, the first antibiotic, in 1928.

- **Statement B**: "The term antibiotic was coined by S. Waxman in 1942."
- This statement is also true. The term "antibiotic" was indeed coined by the scientist Selman Waksman in 1942.

- **Statement C**: "Some persons can be allergic to a particular antibiotic."
- This statement is true. It is well-known that some individuals can have allergic reactions to certain antibiotics.

- **Statement D**: "Each antibiotic is effective only against one particular kind of germ."
- This statement is not true. While some antibiotics are narrow-spectrum (effective against specific types of bacteria), many antibiotics are broad-spectrum, meaning they can act against a wide variety of bacteria, including both gram-positive and gram-negative bacteria. An example of a broad-spectrum antibiotic is ampicillin.

3. **Conclusion**:
- The statement that is not true about antibiotics is **Statement D**: "Each antibiotic is effective only against one particular kind of germ."

### Final Answer:
The correct option that is not true about antibiotics is **D**: "Each antibiotic is effective only against one particular kind of germ."

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