Mammalian follicle was first described by

Options

A. Leewenhock
B. R.D. Graaf
C. Spallazani
D. Von Baer

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks who first described the mammalian follicle.

2. **Recall Key Information**: The mammalian follicle is a significant structure in the reproductive system, particularly in the ovaries, where the egg (ovum) develops.

3. **Name the Contributor**: The mammalian follicle was first described by R.D. Graaf, a Dutch anatomist.

4. **Define the Graafian Follicle**: The Graafian follicle is a fluid-filled structure in the ovary that contains the developing egg. It plays a crucial role in the process of ovulation.

5. **Describe the Structure**: The Graafian follicle consists of:
- An oocyte (the egg).
- Granulosa cells that surround the oocyte.
- An antrum, which is the fluid-filled cavity present in mature follicles.
- Theca cells that are located outside the granulosa cells.

6. **Conclude the Answer**: Therefore, the answer to the question is that the mammalian follicle was first described by R.D. Graaf.

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