To which type of barriers under innate immunity, do the saliva in the mouth and the tears the eyes, belong?

Options

A. Physical barriers
B. Cytokine barriers
C. Cellular barriers
D. Physiological barriers

Answer

**Step-by-Step Solution:**

1. **Understanding Innate Immunity**: Innate immunity is the body's first line of defense against pathogens and is present from birth. It includes various types of barriers that help prevent infections.

2. **Identifying Types of Barriers**: Innate immunity can be categorized into several types of barriers:
- **Physical Barriers**: These include structures like the skin that physically block pathogens.
- **Cytokine Barriers**: These involve signaling proteins that help in immune responses.
- **Cellular Barriers**: These include immune cells like leukocytes (white blood cells) and macrophages that actively fight pathogens.
- **Physiological Barriers**: These consist of bodily fluids and secretions that have antimicrobial properties.

3. **Analyzing the Given Examples**: The question specifically mentions saliva in the mouth and tears in the eyes. Both of these are secretions that play a role in protecting against pathogens.

4. **Classifying Saliva and Tears**:
- **Saliva**: It contains enzymes and antimicrobial substances that help in neutralizing pathogens in the mouth.
- **Tears**: They also contain enzymes (like lysozyme) and antibodies that protect the eyes from infections.

5. **Conclusion**: Since both saliva and tears are bodily fluids that help in fighting off infections, they fall under the category of **physiological barriers** in innate immunity.

**Final Answer**: Saliva in the mouth and tears in the eyes belong to **physiological barriers** under innate immunity.

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