Which one of the following pituitary hormones does not have a target gland to act upon ?

Options

A. Thyrotropin
B. Somatotropin
C. Gonadotropin
D. Adrenocorticotropin

Answer

To determine which pituitary hormone does not have a target gland to act upon, we can analyze the options provided: thyrotropin, somatotropin, gonadotropin, and adrenocorticotropin.

### Step-by-Step Solution:

1. **Understanding Pituitary Hormones**: The pituitary gland secretes various hormones that typically target specific glands or organs in the body to elicit a response.

2. **Analyzing Thyrotropin**:
- Thyrotropin, also known as Thyroid Stimulating Hormone (TSH), stimulates the thyroid gland to produce thyroid hormones (T3 and T4).
- **Conclusion**: Thyrotropin has a specific target gland (the thyroid gland).

3. **Analyzing Somatotropin**:
- Somatotropin, commonly known as Growth Hormone (GH), is involved in growth and metabolism. It affects various tissues throughout the body rather than a specific target gland.
- **Conclusion**: Somatotropin does not have a specific target gland; it acts on multiple tissues and organs.

4. **Analyzing Gonadotropin**:
- Gonadotropins include hormones like Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH), which target the gonads (ovaries and testes) to regulate reproductive functions.
- **Conclusion**: Gonadotropin has specific target glands (the gonads).

5. **Analyzing Adrenocorticotropin**:
- Adrenocorticotropic hormone (ACTH) stimulates the adrenal cortex to release cortisol and other hormones.
- **Conclusion**: Adrenocorticotropin has a specific target gland (the adrenal cortex).

6. **Final Conclusion**:
- Among the options, somatotropin (Growth Hormone) is the only hormone that does not have a specific target gland to act upon. It influences growth and metabolism across various tissues in the body.

### Answer:
**Somatotropin (Growth Hormone)** does not have a target gland to act upon.

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