What is allergy ? Name the antibody responsible for it. Also, mention the two chemicals released from the mast cells during an allergic reaction.

Explanation

### Step-by-Step Solution:

1. **Define Allergy**:
- Allergy is an exaggerated response of the immune system to a certain antigen present in the environment. This means that when the immune system encounters a harmless substance (like pollen, dust, or certain foods), it reacts in an overly aggressive manner, leading to various allergic symptoms.

2. **Identify the Antibody Responsible for Allergy**:
- The antibody responsible for allergic reactions is Immunoglobulin E (IgE). This specific antibody plays a crucial role in the body's immune response to allergens.

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