Consider one of the following is not a constituent of saliva?

Options

A. Bicarbonate
B. Lysozyme
C. Enzymes
D. Immunoglobulin

Answer

**Step-by-Step Solution:**

1. **Understanding Saliva Composition**: Saliva is a fluid secreted in the mouth that plays a crucial role in digestion and oral health. It contains various components that aid in these functions.

2. **Identifying Constituents of Saliva**: The main constituents of saliva include:
- **Ions**: Such as sodium, potassium, calcium, magnesium, bicarbonate, and phosphorus.
- **Immunoglobulins**: These are antibodies that help protect against bacteria and other pathogens.
- **Lysozyme**: An enzyme that has antibacterial properties, helping to break down bacterial cell walls.

3. **Enzymatic Content**: While saliva does contain enzymes, their concentration is relatively low (about 0.01%). These enzymes are primarily involved in the initial stages of digestion, particularly in breaking down carbohydrates.

4. **Identifying the Incorrect Option**: The question asks for a component that is NOT a constituent of saliva. Based on the information provided, the third option (which refers to enzymes in general) is misleading because while enzymes are present, they are not a major constituent compared to ions, immunoglobulins, and lysozyme.

5. **Conclusion**: Therefore, the correct answer to the question "which one of the following is not a constituent of saliva?" is the option that refers to enzymes, as they are not a major constituent compared to the others mentioned.

**Final Answer**: The option that is not a constituent of saliva is the one referring to enzymes.

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