Which of the following components are involved in allergic reaction?

Options

A. IgA and mast cells
B. IgG and basophils
C. IgE and mast cells
D. IgG and mast cells.

Answer

**Step-by-Step Solution:**

1. **Understanding Allergic Reactions**: Allergic reactions occur when the immune system overreacts to a substance (allergen) that is usually harmless. This response involves specific components of the immune system.

2. **Identifying Key Components**: The main components involved in allergic reactions include immunoglobulins (antibodies) and certain types of immune cells. The most relevant immunoglobulin for allergies is IgE.

3. **Role of IgE**: IgE antibodies are produced in response to allergens. They bind to mast cells and basophils, which are types of immune cells that play a crucial role in the allergic response.

4. **Mast Cells and Basophils**: When IgE binds to these cells, it triggers them to release chemicals such as histamine. Histamine is responsible for many of the symptoms associated with allergic reactions, such as swelling, redness, and itching.

5. **Evaluating the Options**:
- **Option 1**: IgA and mast cells - IgA is not involved in allergic reactions.
- **Option 2**: IgG and basophils - IgG is not primarily involved in allergic reactions, although basophils do release histamine.
- **Option 3**: IgE and mast cells - This is the correct option as both IgE and mast cells are directly involved in allergic reactions.
- **Option 4**: IgG and mast cells - Again, IgG is not involved in allergic reactions.

6. **Conclusion**: The correct answer is **Option 3: IgE and mast cells**.

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