Which of the following is/are NOT secretion(s) of islets of Langerhans ?

Options

A. Glucagon
B. Insulin
C. Somatostatin
D. Androgen

Answer

To determine which of the following is/are NOT secretions of the islets of Langerhans, we need to analyze the hormones produced by these pancreatic cells. The options given are glucagon, insulin, somatostatin, and androgen.

### Step-by-Step Solution:

1. **Understanding the Islets of Langerhans**:
- The islets of Langerhans are clusters of cells in the pancreas that produce hormones. They consist of different types of cells, including alpha, beta, delta, F cells, and epsilon cells.

2. **Identifying Hormones Produced**:
- **Alpha Cells**: Produce glucagon.
- **Beta Cells**: Produce insulin.
- **Delta Cells**: Produce somatostatin.
- **F Cells**: Produce pancreatic polypeptide.
- **Epsilon Cells**: Produce ghrelin (the hunger hormone).

3. **Analyzing the Options**:
- **Glucagon**: Produced by alpha cells of the islets of Langerhans.
- **Insulin**: Produced by beta cells of the islets of Langerhans.
- **Somatostatin**: Produced by delta cells of the islets of Langerhans.
- **Androgen**: This is not produced by the islets of Langerhans; it is produced by the adrenal cortex and is involved in male sexual characteristics.

4. **Conclusion**:
- Among the options, glucagon, insulin, and somatostatin are all secretions of the islets of Langerhans, while androgen is not. Therefore, the correct answer is **androgen**.

### Final Answer:
The secretion that is NOT produced by the islets of Langerhans is **androgen** (Option D).

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