Islets of Langerhans are present in

Options

A. Brain
B. Stomach
C. Ovary
D. Pancreas.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where the Islets of Langerhans are located.

2. **Identifying the Options**: The options given are:
- 1st: Brain
- 2nd: Stomach
- 3rd: Ovary
- 4th: Pancreas

3. **Knowledge of Islets of Langerhans**: The Islets of Langerhans are clusters of cells found in the pancreas. They are part of the endocrine system and are responsible for producing hormones.

4. **Function of Islets of Langerhans**:
- They contain different types of cells:
- **Alpha cells** (about 25%): Secrete glucagon, which raises blood glucose levels.
- **Beta cells** (about 60%): Secrete insulin, which lowers blood glucose levels.
- **Delta cells** (about 10%): Secrete somatostatin, which regulates the endocrine system and affects the function of other hormones.

5. **Conclusion**: Based on the information, the Islets of Langerhans are located in the pancreas.

6. **Final Answer**: Therefore, the correct option is **4th: Pancreas**.

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