Immunoglobulin that increases in number during allergy is

Options

A. IgA
B. IgE
C. IgG
D. IgM

Answer

**Step-by-Step Solution:**

1. **Understanding Immunoglobulins**: Immunoglobulins, also known as antibodies, are proteins produced by the immune system to identify and neutralize foreign objects like bacteria and viruses. There are several types of immunoglobulins, including IgA, IgG, IgE, and IgM.

2. **Identifying the Types of Immunoglobulins**:
- **IgA**: This immunoglobulin primarily increases during infections and is found in mucosal areas, such as the gut and respiratory tract.
- **IgG**: This is the most abundant antibody in the blood and is crucial for fighting bacterial and viral infections.
- **IgM**: This immunoglobulin is the first to respond to an infection and is effective in binding to pathogens.
- **IgE**: This immunoglobulin is specifically associated with allergic reactions and is responsible for mediating responses to allergens.

3. **Analyzing the Question**: The question asks which immunoglobulin increases in number during allergic reactions.

4. **Conclusion**: Based on the functions of the immunoglobulins, IgE is the antibody that increases in response to allergens, such as in cases of asthma or sinusitis. Therefore, the correct answer to the question is **IgE**.

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