Which one is without a specific target organ?

Options

A. Thyrotropin
B. Gonadotropin
C. Somatotrophin
D. Adrenocortitropin.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which hormone is without a specific target organ among the given options: thyrotrophin, gonadotrophin, somatotrophin, or adrenocorticotrophin.

2. **Identifying the Hormones**:
- **Thyrotrophin (TSH)**: Stimulates the thyroid gland to produce thyroid hormones.
- **Gonadotrophin (LH and FSH)**: Stimulates the gonads (ovaries and testes) to produce sex hormones and gametes.
- **Somatotrophin (Growth Hormone)**: Promotes growth and metabolism in various tissues.
- **Adrenocorticotrophin (ACTH)**: Stimulates the adrenal cortex to produce cortisol.

3. **Analyzing Target Organs**:
- **Thyrotrophin** has a specific target organ (thyroid gland).
- **Gonadotrophin** has specific target organs (gonads).
- **Adrenocorticotrophin** has a specific target organ (adrenal cortex).
- **Somatotrophin** does not have a specific target organ; it acts on all cells in the body.

4. **Conclusion**: Based on the analysis, somatotrophin (growth hormone) is the hormone that does not have a specific target organ.

5. **Final Answer**: Somatotrophin is the correct answer.

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