THE estrogen in mainly synthesised and secreted by

Options

A. Rupture follicles in ovary
B. Corpus luteum
C. Growing ovarian follicles
D. Leydig cells

Answer

**Step-by-step Solution:**

1. **Understanding the Question**: The question asks where estrogen is mainly synthesized and secreted. To answer this, we need to identify the specific cells or structures responsible for the production of estrogen in the female reproductive system.

2. **Role of Follicles**: In females, the maturation of ovarian follicles is crucial for the production of estrogen. Follicles are structures that contain developing eggs and are essential for the reproductive cycle.

3. **Granulosa Cells**: Within the follicles, there are specific cells called granulosa cells. These cells play a significant role in the maturation of the follicles and are responsible for the synthesis of estrogen.

4. **Influence of FSH**: The maturation of the follicles is stimulated by the hormone Follicle Stimulating Hormone (FSH), which is secreted by the anterior pituitary gland. FSH promotes the growth and development of ovarian follicles, leading to increased estrogen production.

5. **Theca Interna Layer**: The follicles consist of two layers: the inner layer called the theca interna and the outer layer called the theca externa. The theca interna is particularly important as it works in conjunction with granulosa cells to produce estrogen.

6. **Conclusion**: Based on the above information, we can conclude that estrogen is mainly synthesized and secreted by the granulosa cells of the growing ovarian follicles (specifically the mature follicles).

**Final Answer**: Estrogen is mainly synthesized and secreted by the granulosa cells of the growing ovarian follicles.

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