In oogenesis, all divisions are mitotic except during the formation of

Options

A. oogonia
B. primary oocytes
C. first polar body
D. second polar body

Answer

**Step-by-Step Solution:**

1. **Understanding Oogenesis**: Oogenesis is the process of egg (ovum) formation in females. It involves several stages of cell division.

2. **Identifying Types of Cell Division**: In oogenesis, there are two types of cell division: mitosis and meiosis. Mitosis is a process of cell division that results in two identical daughter cells, while meiosis is a specialized form of cell division that reduces the chromosome number by half, resulting in gametes.

3. **Mitosis in Oogenesis**: During the early stages of oogenesis, specifically in the formation of oogonia (the initial germ cells), the divisions are mitotic. This occurs during fetal development.

4. **Meiosis in Oogenesis**: The process of meiosis begins when the primary oocyte is formed. The primary oocyte undergoes meiosis, which includes two divisions: meiosis I and meiosis II.

5. **Identifying the Exception**: The question asks for the exception where all divisions are not mitotic. The key point here is that during the formation of the first polar body, meiosis occurs. The first polar body is produced during the first meiotic division of the primary oocyte.

6. **Conclusion**: Therefore, in oogenesis, all divisions are mitotic except during the formation of the first polar body, where meiosis occurs.

**Final Answer**: In oogenesis, all divisions are mitotic except during the formation of the **first polar body**.

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