Which is not a component of nonspecific defence

Options

A. Mucous membrane
B. Phagocytosis
C. Lysozyme
D. Killer T-cells

Answer

**Step-by-Step Solution:**

1. **Understanding Nonspecific Defense Mechanisms:**
- Nonspecific defense mechanisms are the body's first line of defense against pathogens. They include physical barriers and immune responses that do not target specific pathogens.

2. **Identifying Components of Nonspecific Defense:**
- Common components of nonspecific defense include:
- **Mucous Membrane:** Acts as a barrier to trap pathogens.
- **Phagocytosis:** A process where certain cells (like macrophages) engulf and destroy pathogens.
- **Lysozyme:** An enzyme found in various secretions (like saliva and tears) that breaks down bacterial cell walls.

3. **Analyzing the Options:**
- The options given are:
- Mucous membrane
- Phagocytosis
- Lysozyme
- Killer T cells
- The first three options (mucous membrane, phagocytosis, and lysozyme) are all components of the nonspecific defense system.

4. **Identifying the Outlier:**
- **Killer T cells** are part of the adaptive immune system and are involved in the specific immune response. They target specific antigens and are not part of the nonspecific defense mechanisms.

5. **Conclusion:**
- Therefore, the component that is not part of nonspecific defense is **Killer T cells**.

**Final Answer: Killer T cells**

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