Beta cells of islets of langerhans secrete_____

Answer

**Step-by-Step Solution:**

1. **Identify the Location**: The beta cells are located in the islets of Langerhans, which are found in the pancreas.

2. **Understand the Function of Beta Cells**: Beta cells are one of the three types of cells in the islets of Langerhans. The other two types are alpha cells and delta cells.

3. **Know the Hormones Secreted**: The primary hormone secreted by beta cells is insulin.

4. **Recognize the Role of Insulin**: Insulin plays a crucial role in regulating carbohydrate and fat metabolism in the body. It helps cells absorb glucose from the bloodstream.

5. **Implications of Insulin Deficiency**: A deficiency of insulin can lead to diabetes mellitus, a condition characterized by high blood sugar levels.

6. **Conclusion**: Therefore, the beta cells of the islets of Langerhans secrete insulin.

**Final Answer**: Beta cells of islets of Langerhans secrete insulin.

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