The specific feedback effector for follicle-stimulating hormone (FSH) is

The specific feedback effector for follicle-stimulating hormone (FSH) is

• A. Inhibin
• B. Activin
• C. Progesterone
• D. Estradiol

Answer: (A)

The main idea is that FSH is controlled by a molecule that provides targeted negative feedback to its production. Inhibin, produced by ovarian granulosa cells as follicles develop, acts on the anterior pituitary to specifically suppress FSH secretion. This helps fine-tune follicle development by lowering FSH levels when appropriate. Activin does the opposite, promoting FSH production rather than inhibiting it. Estradiol and progesterone influence the axis more broadly, affecting GnRH pulse dynamics and pituitary sensitivity, but they do not provide the precise, FSH-specific feedback that inhibin does.

The main idea is that FSH is controlled by a molecule that provides targeted negative feedback to its production. Inhibin, produced by ovarian granulosa cells as follicles develop, acts on the anterior pituitary to specifically suppress FSH secretion. This helps fine-tune follicle development by lowering FSH levels when appropriate. Activin does the opposite, promoting FSH production rather than inhibiting it. Estradiol and progesterone influence the axis more broadly, affecting GnRH pulse dynamics and pituitary sensitivity, but they do not provide the precise, FSH-specific feedback that inhibin does.