Memory cells are formed from:

Options

A. moncytes
B. eosinophils
C. neutrophils
D. lymphocytes

Answer

**Step-by-Step Solution:**

1. **Understanding Memory Cells**: Memory cells are a type of immune cell that play a crucial role in the adaptive immune response. They are responsible for "remembering" past infections and enabling a faster response upon re-exposure to the same pathogen.

2. **Identifying Cell Types**: The question presents several types of white blood cells: monocytes, eosinophils, neutrophils, and lymphocytes. Each of these cells has different functions in the immune system.

3. **Focusing on Lymphocytes**: Among the listed cell types, lymphocytes are specifically involved in the adaptive immune response. They include T cells and B cells, both of which can form memory cells after an initial exposure to an antigen.

4. **Confirming the Source of Memory Cells**: Memory cells are primarily derived from T lymphocytes (T cells). When T cells encounter an antigen, they can differentiate into memory T cells, which persist long-term in the body.

5. **Conclusion**: Therefore, the correct answer to the question "Memory cells are formed from:" is lymphocytes, specifically T lymphocytes.

**Final Answer**: Memory cells are formed from lymphocytes (specifically T lymphocytes).

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