Acid neutraliser present in mucus of saliva is

Options

A. Bicarbonate ion
B. Thiocyanate
C. Sodium acetate
D. Sodium hydroxide

Answer

To solve the question regarding the acid neutralizer present in the mucus of saliva, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Composition of Saliva**: Saliva is produced by the salivary glands and contains various components including water, electrolytes, mucus, and enzymes.

2. **Identify the Role of Mucus in Saliva**: The mucus in saliva serves several functions, one of which is to provide a medium for enzymes to act and to help in the lubrication of food.

3. **Recognize the Importance of pH in Saliva**: The pH of saliva is generally between 6.2 to 7.2, which is slightly basic. This pH is crucial for the proper functioning of enzymes present in saliva, such as salivary amylase.

4. **Determine the Acid Neutralizer**: Among the options provided (bicarbonate ion, thiocyanate, sodium acetate, sodium hydroxide), we need to identify which one acts as an acid neutralizer.

5. **Identify Bicarbonate Ions**: Bicarbonate ions (HCO3-) are known to neutralize acids. They help maintain the alkaline environment in the mouth by neutralizing any acids that may be present.

6. **Conclusion**: Based on the information, the acid neutralizer present in the mucus of saliva is the bicarbonate ion. Therefore, the correct answer is option number 1.

### Final Answer:
The acid neutralizer present in the mucus of saliva is **bicarbonate ion**.

---