The chemical substances produced by some microbes which can kill or tetrad the growth of other microbes are called -

Options

A. toddy
B. lactic acid
C. antibiotics
D. ethanol

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks about chemical substances produced by some microbes that can kill or inhibit the growth of other microbes.

2. **Identifying the Term**: The chemical substances that fit this description are known as "antibiotics."

3. **Definition of Antibiotics**: Antibiotics are substances that can kill or inhibit the growth of bacteria. The prefix "anti-" means against, and "biotic" refers to life, hence antibiotics are substances that work against living microorganisms.

4. **Historical Context**: The first antibiotic discovered was Penicillin. It was discovered by Alexander Fleming in 1928 when he was studying the bacterium Streptococcus.

5. **Function of Penicillin**: Penicillin is a type of antibiotic that is produced by the mold Penicillium. It works by interfering with the ability of bacteria to form cell walls, which ultimately leads to their death.

6. **Conclusion**: Therefore, the answer to the question is that the chemical substances produced by some microbes which can kill or inhibit the growth of other microbes are called antibiotics.

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