Which substance of saliva destroy the harmful bacteria -

Options

A. Cerumin
B. Chyme
C. Lysozyme
D. Secretin

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which substance in saliva is responsible for destroying harmful bacteria.

2. **Analyzing the Options**: The options provided are:
- Cerumen
- Chyme
- Lysozyme
- Secretin

3. **Evaluating Cerumen**:
- Cerumen is commonly known as earwax.
- Its primary function is to protect the ear canal from water, damage, infection, and foreign bodies.
- Since cerumen is not related to saliva, it cannot be the correct answer.

4. **Evaluating Chyme**:
- Chyme is the semi-fluid mass of partly digested food that is formed in the stomach.
- It is not produced in the mouth and is not a component of saliva.
- Therefore, chyme is also not the correct answer.

5. **Evaluating Secretin**:
- Secretin is a hormone that regulates gastric acid secretion, pancreatic bicarbonate secretion, and osmoregulation.
- It does not have a role in saliva or in destroying bacteria.
- Thus, secretin is not the correct answer.

6. **Evaluating Lysozyme**:
- Lysozyme is an enzyme found in saliva that has bacteriolytic properties, meaning it can kill bacteria.
- It works by breaking down the cell walls of bacteria, effectively destroying them.
- Additionally, lactoferrin, another component of saliva, inhibits bacterial growth by binding iron, which is essential for bacterial multiplication.

7. **Conclusion**: Based on the evaluation of all the options, the correct answer is **lysozyme**, as it is the substance in saliva that destroys harmful bacteria.

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