Stages of Plasmodium discovered by Ronald Ross in female Anopheles mosquito

Options

A. Sporozoites
B. Oocysts
C. Gametocytes
D. Merozoites

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the stages of the Plasmodium parasite that were discovered by Ronald Ross in the female Anopheles mosquito.

2. **Identifying the Key Scientist**: Ronald Ross is the scientist known for his work on malaria and the life cycle of the Plasmodium parasite.

3. **Recognizing the Relevant Stages**: The stages of Plasmodium that are typically mentioned include:
- Spores (sporozoites)
- Oocysts
- Gametocytes
- Merozoites

4. **Focusing on Ronald Ross's Discovery**: Among these stages, Ronald Ross is specifically credited with discovering the **oocyst stage** of the Plasmodium parasite.

5. **Location of Discovery**: He discovered the oocyst stage in the mid-gut of the female Anopheles mosquito. This is the part of the mosquito's stomach where the oocysts develop.

6. **Historical Context**: Ronald Ross made this discovery on **August 20, 1897**, marking a significant milestone in the understanding of malaria transmission.

7. **Conclusion**: The correct answer to the question is the **oocyst stage** of the Plasmodium parasite, as discovered by Ronald Ross.

### Final Answer:
The stage of Plasmodium discovered by Ronald Ross in the female Anopheles mosquito is the **oocyst stage**.

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