During Allergy acidophil secrete `:-`

Options

A. Histamine
B. Heparin
C. Prothrombin
D. Serotonin

Answer

**Step-by-Step Solution:**

1. **Understanding the Context**: The question asks about the secretion of a substance by acidophils during an allergic reaction.

2. **Identifying Acidophils**: Acidophils are a type of white blood cell that play a role in the immune response. They are often associated with allergic reactions.

3. **Reviewing the Options**: The options provided are:
- Histamine
- Heparin
- Prothrombin
- Serotonin

4. **Analyzing Histamine**: Histamine is a chemical that is released during allergic reactions. It is known to cause symptoms such as itching, sneezing, and swelling.

5. **Connection to Allergic Reactions**: Histamine is released by mast cells and basophils during type 1 hypersensitivity reactions, which are common in allergies.

6. **Conclusion**: Since histamine is the substance that is primarily involved in allergic reactions and is secreted by cells involved in the immune response, the correct answer is that during an allergy, acidophils secrete histamine.

**Final Answer**: During an allergy, acidophils secrete **histamine**.

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