Which one of the following is the incorrect matching of the hormone with its source /secretion/disease

Options

A. Glucagon - Beta cells (source)
B. Somatostatin - Delta cells (source)
C. Corpus luteum - Relaxin (secretion)
D. Insulin - Diabetes mellitus (disease)

Explanation

To solve the question regarding the incorrect matching of hormones with their source/secretion/disease, follow these steps:

### Step-by-Step Solution:

1. **Identify the Hormones and Their Sources**:
- The question provides several hormones and their supposed sources. We need to verify each pairing.

2. **Check the First Option**:
- **Glucagon**: It is stated that glucagon is secreted by the beta cells.
- **Correction**: Glucagon is actually secreted by the **alpha cells** of the pancreas, not the beta cells. This is an incorrect matching.

3. **Check the Second Option**:
- **Insulin**: The option states that insulin causes diabetes mellitus.
- **Verification**: Insulin is secreted by the **beta cells** of the pancreas, and a deficiency in insulin leads to diabetes mellitus. This is a correct matching.

4. **Check the Third Option**:
- **Somatostatin**: The option states that somatostatin is secreted by the delta cells.
- **Verification**: Somatostatin is indeed secreted by the **delta cells** of the pancreas. This is a correct matching.

5. **Check the Fourth Option**:
- **Relaxin**: The option states that relaxin is secreted by the corpus luteum.
- **Verification**: The corpus luteum does secrete relaxin during pregnancy, which helps in relaxing uterine muscles. This is also a correct matching.

6. **Conclusion**:
- The only incorrect matching found is in the first option regarding glucagon and its source. Therefore, the answer to the question is that the incorrect matching is **option number one**.

### Final Answer:
- The incorrect matching of the hormone with its source/secretion/disease is **option number one** (Glucagon - beta cells).

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