Glucagon produced by alpha cells of islet of Langerhans which :-

Options

A. Converts glucose to glycogen
B. Converts glycogen to glucose
C. Decreases concentration of glucose in blood
D. None of the above

Answer

**Step-by-Step Solution:**

1. **Understanding Glucagon**: Glucagon is a peptide hormone produced by the alpha cells of the islets of Langerhans in the pancreas. Its primary role is to regulate blood glucose levels.

**Hint**: Remember that glucagon is produced by alpha cells and is involved in increasing blood glucose levels.

2. **Function of Glucagon**: The main function of glucagon is to increase blood glucose levels when they are low. It does this through several mechanisms:
- It stimulates the conversion of glycogen (stored glucose) in the liver back into glucose.
- It promotes gluconeogenesis, which is the production of glucose from non-carbohydrate sources like amino acids and fatty acids.
- It reduces the consumption of glucose by the liver and body cells, ensuring that more glucose is available in the bloodstream.

**Hint**: Focus on how glucagon acts to increase glucose levels rather than decrease them.

3. **Analyzing the Options**: Now, let's analyze the given options:
- **Converts glucose to glycogen**: This is incorrect. Glucagon does not convert glucose to glycogen; that function is performed by insulin.
- **Converts glycogen to glucose**: This is correct. Glucagon stimulates the conversion of glycogen to glucose.
- **Decreasing concentration of glucose in blood**: This is incorrect. Glucagon increases the concentration of glucose in the blood.
- **None of the above**: This is also incorrect since one of the options is true.

**Hint**: Look for the option that aligns with glucagon's role in increasing blood glucose levels.

4. **Conclusion**: The correct answer is that glucagon produced by alpha cells of the islet of Langerhans converts glycogen to glucose.

**Final Answer**: The correct option is **Option B: Converts glycogen to glucose**.

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