Which phase of Plasmodium is resistant to drugs ?

Options

A. Pre-erythrocytic phase
B. Posterythrocytic phase
C. Erythrocytic phase
D. Gamogonic phase

Answer

To determine which phase of Plasmodium is resistant to drugs, we can analyze each phase of its life cycle:

1. **Understanding the Life Cycle of Plasmodium**:
- Plasmodium has several phases in its life cycle: pre-erythrocytic phase, erythrocytic phase, post-erythrocytic phase, and gammogonic phase. Each phase has different characteristics and interactions with the host's body.

2. **Evaluating Each Phase**:
- **Gammogonic Phase**: This phase involves the production of gametes. Since it is focused on reproduction, it does not require drugs for intervention, making it an incorrect option.
- **Erythrocytic Phase**: This is the phase where merozoites invade red blood cells. Drugs can effectively target and control the merozoites during this phase, so it is also not the correct answer.
- **Pre-Erythrocytic Phase**: In this phase, sporozoites enter the bloodstream and migrate to the liver. Drugs can prevent the infection at this stage, so it is not the correct option either.
- **Post-Erythrocytic Phase**: This phase occurs after the erythrocytic phase and involves some merozoites that can damage liver cells. This phase is resistant to drugs, as the damage done to the liver cells cannot be effectively prevented by any available drugs.

3. **Conclusion**:
- Based on the analysis, the phase of Plasmodium that is resistant to drugs is the **post erythrocytic phase**.

**Final Answer**: The post erythrocytic phase is resistant to drugs.

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