Which of the following cells secrete histamine

Options

A. Plasma cells
B. Mast cells
C. Monocytes
D. N.K. cells

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which type of cells secrete histamine. Histamine is a chemical involved in immune responses, particularly in allergic reactions.

2. **Identifying Cell Types**: The options provided likely include various types of immune cells. Common types include plasma cells, mast cells, monocytes, and non-killer cells (which are a type of lymphocyte).

3. **Analyzing Plasma Cells**: Plasma cells are responsible for producing antibodies when stimulated by an antigen. They do not secrete histamine. Thus, plasma cells can be ruled out as the correct answer.

4. **Identifying Mast Cells**: Mast cells are known for their role in allergic reactions. They release histamine when they encounter allergens. This release of histamine leads to the symptoms associated with allergies, such as itching, swelling, and redness.

5. **Examining Monocytes**: Monocytes are a type of white blood cell (WBC) that play a role in the immune response but do not secrete histamine. They differentiate into macrophages and dendritic cells to help fight infections.

6. **Considering Non-Killer Cells**: Non-killer cells, or helper T-cells, do not secrete histamine. They assist in the immune response but are not involved in the direct secretion of histamine.

7. **Conclusion**: Based on the analysis, the only cells that secrete histamine are mast cells. Therefore, the correct answer to the question is option number two, which refers to mast cells.

**Final Answer**: Mast cells secrete histamine.

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