`alpha-" and" beta`-cells in the islets of Langerhans are respectively defunctioned by

Options

A. Mercuric chloride and alloxan
B. Alloxan and DDT
C. Alloxan and cobalt chloride
D. Cobalt chloride and alloxan.

Answer

To answer the question regarding the defunctioning of alpha and beta cells in the islets of Langerhans, we will follow these steps:

### Step 1: Understand the Islets of Langerhans
The islets of Langerhans are clusters of cells in the pancreas that play a crucial role in regulating blood sugar levels. They consist of different types of cells, primarily alpha cells and beta cells.

### Step 2: Identify the Functions of Alpha and Beta Cells
- **Alpha Cells**: These cells secrete the hormone glucagon, which raises blood glucose levels.
- **Beta Cells**: These cells secrete the hormone insulin, which lowers blood glucose levels.

### Step 3: Determine the Need for Defunctioning
To study the function of one type of cell, researchers often need to defunction the other type. This means they will inhibit the activity of one type of cell to observe the effects of the other.

### Step 4: Identify the Chemicals Used for Defunctioning
- **Eloxin**: This chemical is used to defunction beta cells. By using eloxin, researchers can inhibit insulin secretion and study the effects of glucagon from alpha cells.
- **Cobalt Chloride**: This chemical is used to defunction alpha cells. By using cobalt chloride, researchers can inhibit glucagon secretion and study the effects of insulin from beta cells.

### Step 5: Conclusion
Thus, the correct answer to the question is:
- Alpha cells are defunctioned by **Cobalt Chloride**.
- Beta cells are defunctioned by **Eloxin**.

### Final Answer
The alpha and beta cells in the islets of Langerhans are respectively defunctioned by Cobalt Chloride and Eloxin.

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