Which one of the following paise is incorrectly matched ?

Options

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

Answer

To solve the question of which pair is incorrectly matched, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understanding Glucagon and Beta Cells**:
- Glucagon is a hormone that plays a crucial role in glucose metabolism.
- It is secreted by the **alpha cells** of the pancreas, not the beta cells.
- The beta cells are responsible for producing **insulin**.

**Conclusion**: The statement that glucagon is secreted from the beta cells is incorrect.

2. **Understanding Somatostatin and Delta Cells**:
- Somatostatin is a hormone secreted by the **delta cells** of the pancreas.
- This statement is correct as delta cells are known to produce somatostatin.

3. **Understanding Relaxin and Corpus Luteum**:
- Relaxin is a hormone that is produced by the **corpus luteum** during pregnancy.
- It is also released from the placenta.
- This statement is correct as well.

4. **Understanding Insulin and Diabetes Mellitus**:
- Insulin is a hormone produced by the beta cells of the pancreas.
- A deficiency in insulin leads to **diabetes mellitus**, which is characterized by high blood sugar levels.
- This statement is also correct.

### Final Conclusion:
After analyzing all the options, the only incorrect match is the first option, which states that glucagon is secreted from the beta cells. Therefore, the answer to the question is:

**Answer**: Glucagon is secreted from the beta cells (incorrectly matched).

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