Anamnestic response is caused by :-

Options

A. Memory cells
B. Helper T-cells
C. T-killer
D. Cancer cells

Answer

**Step-by-Step Solution:**

1. **Understanding Anamnestic Response**:
- The anamnestic response, also known as the secondary immune response, occurs when the immune system encounters an antigen for the second time or more. This response is typically stronger and faster than the primary immune response.

2. **Primary vs. Secondary Immune Response**:
- The primary immune response is the initial reaction of the immune system when it first encounters an antigen. This involves the activation of naive B cells and T cells.
- The secondary immune response (anamnestic response) occurs upon re-exposure to the same antigen, utilizing memory cells that were formed during the primary response.

3. **Role of Memory Cells**:
- Memory cells, specifically memory B cells, are responsible for the anamnestic response. They "remember" the specific antigen and can mount a quicker and more effective response upon subsequent exposures.

4. **Evaluating the Options**:
- The options given are:
- A) Memory cells
- B) Helper T cells
- C) T killer cells
- D) Cancer cells
- Among these, memory cells are specifically involved in the anamnestic response.

5. **Conclusion**:
- Therefore, the correct answer to the question "Anamnestic response is caused by:" is **A) Memory cells**.

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