The LH and FSH secretion from the anterior pituitary is Stimulated by the

Options

A. gonadotropin releasing hormone .
B. testosterone from testis
C. melatonin from pineal gland
D. thyroxine from thyroid gland

Answer

To solve the question regarding what stimulates the secretion of LH (Luteinizing Hormone) and FSH (Follicle Stimulating Hormone) from the anterior pituitary, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Hormones in Question**:
- We are looking at LH and FSH, which are both gonadotropins produced by the anterior pituitary gland.

2. **Understand the Role of Gonadotropins**:
- Gonadotropins, such as LH and FSH, are involved in regulating gonadal activity (testes in males and ovaries in females).

3. **Locate the Source of Stimulation**:
- The secretion of LH and FSH is regulated by the hypothalamus, which releases specific hormones that act on the pituitary gland.

4. **Identify the Key Hormone**:
- The hormone that stimulates the anterior pituitary to release LH and FSH is Gonadotropin-Releasing Hormone (GnRH).

5. **Evaluate Other Options**:
- Testosterone from the testes, melatonin from the pineal gland, and thyroxin from the thyroid gland do not stimulate the secretion of LH and FSH directly.
- Testosterone is a product of the gonadal activity that is regulated by LH and FSH, while melatonin and thyroxin have different functions unrelated to the stimulation of LH and FSH.

6. **Conclusion**:
- Therefore, the correct answer is Gonadotropin-Releasing Hormone (GnRH) as it is the hormone that stimulates the secretion of LH and FSH from the anterior pituitary.

### Final Answer:
The LH and FSH secretion from the anterior pituitary is stimulated by Gonadotropin-Releasing Hormone (GnRH).

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