The first round of meiosis of oogonium is completed in

Options

A. graffine follocile
B. secondary follicile
C. primary follicile
D. tertiary follicle

Answer

To solve the question regarding when the first round of meiosis of an oogonium is completed, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Oogonium**: An oogonium is the female germ cell that undergoes meiosis to form ova (egg cells).

2. **Meiosis Overview**: Meiosis is a type of cell division that reduces the chromosome number by half, resulting in four haploid cells from one diploid cell. The first round of meiosis is called meiosis I.

3. **Stages of Oogenesis**: The process of oogenesis involves several stages:
- Oogonium (diploid)
- Primary oocyte (arrested in prophase I)
- Secondary oocyte (after the completion of meiosis I)
- Ovum (after the completion of meiosis II)

4. **Arrested Development**: The primary oocyte is arrested in prophase I of meiosis until puberty. Upon reaching puberty, the primary oocyte completes meiosis I and is released as a secondary oocyte.

5. **Formation of Follicles**: As the primary oocyte develops, it forms structures known as follicles:
- Primary follicle
- Secondary follicle
- Tertiary follicle (also known as Graafian follicle)

6. **Completion of Meiosis I**: The first round of meiosis (meiosis I) is completed when the primary oocyte divides to form a secondary oocyte and a polar body. This occurs during the development of the tertiary follicle.

7. **Conclusion**: Therefore, the first round of meiosis of the oogonium is completed in the tertiary follicle.

### Final Answer:
The first round of meiosis of oogonium is completed in the **tertiary follicle**.

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