Antrum is filled with fluid and is found in

Options

A. Bone-marrow of bone
B. Cavity of brain
C. Graffian follicle of ovary
D. Pericardium of heart

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where the antrum, which is filled with fluid, is found.

2. **Analyzing the Options**:
- **Option 1**: Bone marrow of the bone - This is not related to antrum.
- **Option 2**: Cavity of the brain - The brain has ventricles filled with cerebrospinal fluid, but this is not referred to as antrum.
- **Option 3**: Graphene follicle of the ovary - This is a structure in the female reproductive system that contains an antrum.
- **Option 4**: Pericardium of the heart - This is a membrane surrounding the heart, not related to antrum.

3. **Identifying the Correct Answer**: The antrum is specifically associated with the Graphene follicle (also known as the tertiary follicle) in the ovary, where it is a fluid-filled cavity.

4. **Explanation of the Graphene Follicle**:
- During oogenesis (the formation of ova), primary oocytes are surrounded by granulosa cells, forming primary follicles.
- As development continues, these primary follicles develop into secondary follicles with more layers of granulosa cells.
- Eventually, they mature into tertiary follicles, known as Graphene follicles, which are characterized by the presence of the antrum.

5. **Conclusion**: Therefore, the correct answer is that the antrum is found in the Graphene follicle of the ovary.

**Final Answer**: The antrum is filled with fluid and is found in the Graphene follicle of the ovary.

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