Penicillin inhibits .

Options

A. Transcription
B. Translation
C. Regulation
D. Cellwall synthesis

Answer

**Step-by-Step Solution:**

1. **Understanding Penicillin**: Penicillin is an antibiotic that was the first to be discovered. It is derived from the mold Penicillium notatum and was discovered by Alexander Fleming.

2. **Function of Antibiotics**: Antibiotics are agents that either kill bacteria or inhibit their growth. They are specifically effective against bacterial infections.

3. **Mechanism of Action of Penicillin**: Penicillin works primarily by inhibiting the synthesis of the bacterial cell wall. The cell wall is crucial for maintaining the structural integrity of bacteria.

4. **Impact of Inhibition**: When penicillin inhibits cell wall synthesis, bacteria become vulnerable and cannot maintain their shape or protect themselves from their environment. This leads to their inability to survive and reproduce.

5. **Limitations of Penicillin**: It is important to note that penicillin is not effective against all types of bacteria. For example, it does not work on mycoplasma because these bacteria lack a cell wall.

6. **Conclusion**: Based on the mechanism of action of penicillin, the correct answer to the question "Penicillin inhibits" is D. Cellular Synthesis, specifically referring to the synthesis of the bacterial cell wall.

**Final Answer**: D. Cellular Synthesis (specifically cell wall synthesis)

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