In the ovum of rabbit, Graafian follicle is

Options

A. Oogonial cells
B. Corpus luteum
C. Corpus albicans
D. Theca externa, theca interna, oocyte & follicle cells

Explanation

**Step-by-Step Solution:**

1. **Understanding the Graafian Follicle**: The Graafian follicle, also known as the mature follicle, is a structure in the ovary that contains the ovum (egg) and is essential for reproduction.

2. **Structure of the Graafian Follicle**: The Graafian follicle has several layers:
- **Theca Externa**: This is the outer layer of the follicle, composed of connective tissue.
- **Theca Interna**: This is the inner layer, which is responsible for producing hormones, particularly estrogen.
- **Granulosa Cells**: These are the cells that surround the ovum and are involved in the nourishment and support of the developing egg.

3. **Location of the Ovum**: The ovum is located at the center of the Graafian follicle, surrounded by the granulosa cells.

4. **Hormonal Function**: The theca interna plays a crucial role in hormone production, specifically in the synthesis of estrogen, which is vital for the regulation of the female reproductive cycle.

5. **Conclusion**: Based on the structure and function of the Graafian follicle, we can summarize that it consists of the theca externa, theca interna, granulosa cells, and the ovum.

**Final Answer**: The Graafian follicle in the ovum of a rabbit consists of the theca externa, theca interna, granulosa cells, and the ovum.

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