Meiosis during sperm formation of Ascaris, was first observed by

Options

A. Fleming
B. Boveri
C. Brauer
D. De Vries

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks who first observed meiosis during sperm formation in Ascaris. Ascaris is a genus of parasitic roundworms, and the process of sperm formation is known as spermatogenesis.

2. **Identifying the Process**: Spermatogenesis occurs in the testes and involves several stages:
- **Spermatogonia**: These are the initial germ cells that undergo mitosis.
- **Primary Spermatocyte**: The spermatogonia divide to form primary spermatocytes.
- **Meiosis I**: The primary spermatocyte undergoes meiosis I to produce secondary spermatocytes.
- **Meiosis II**: The secondary spermatocytes then undergo meiosis II to form spermatids, which mature into spermatozoa.

3. **Recognizing Key Scientists**: The question provides four options: Fleming, Bovary, Brouwer, and De Rijs. We need to identify which of these scientists first observed meiosis in Ascaris.

4. **Finding the Correct Answer**: Based on historical scientific contributions, it is known that the first observation of meiosis during sperm formation in Ascaris was made by Brouwer.

5. **Conclusion**: Therefore, the correct answer to the question is option 3, Brouwer.

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