In a maturing Graafian follicle the granulosa cells secrete ……… into the blood .

Options

A. Estrogen
B. progesterones
C. LH
D. FSH

Answer

**Step-by-Step Solution:**

1. **Understanding the Graafian Follicle**: The Graafian follicle is a mature ovarian follicle that has developed from a primary follicle. It contains a primary oocyte surrounded by layers of granulosa cells.

2. **Role of Granulosa Cells**: Granulosa cells are specialized cells that surround the oocyte in the follicle. They play a crucial role in the development and maturation of the oocyte and are involved in hormone secretion.

3. **Hormonal Secretion**: In a maturing Graafian follicle, the granulosa cells secrete hormones into the bloodstream. The primary hormone secreted by these cells is crucial for regulating the menstrual cycle.

4. **Identifying the Hormone**: The main hormone secreted by the granulosa cells is estrogen. Estrogen is an ovarian hormone that is essential for the regulation of the menstrual cycle and the development of secondary sexual characteristics in females.

5. **Conclusion**: Therefore, the correct answer to the question is that the granulosa cells in a maturing Graafian follicle secrete **estrogen** into the blood.

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