Carbohydrate digestion occurs first in which structure ?

Options

A. mouth
B. intestine
C. Stomach
D. none of these

Answer

**Step-by-Step Solution:**

1. **Understanding Carbohydrate Digestion**: Carbohydrate digestion refers to the process where complex carbohydrates (polysaccharides) are broken down into simpler sugars (monosaccharides), primarily glucose.

2. **Identifying the Site of Digestion**: The question asks where carbohydrate digestion begins. We need to consider the different parts of the digestive system: mouth, stomach, and intestine.

3. **Role of the Mouth**: The mouth is the first site of digestion. When food enters the mouth, it is mechanically broken down by chewing. This process is known as mechanical digestion.

4. **Saliva and Enzymes**: As we chew, saliva is secreted from the salivary glands. Saliva contains an enzyme called salivary amylase, which is crucial for carbohydrate digestion. This enzyme starts breaking down complex carbohydrates into simpler sugars.

5. **Conclusion**: Since carbohydrate digestion begins in the mouth due to the action of salivary amylase, the correct answer to the question is "mouth".

6. **Elimination of Other Options**:
- **Intestine**: While carbohydrates are further digested and absorbed in the intestine, this is not where digestion begins.
- **Stomach**: No significant carbohydrate digestion occurs in the stomach.
- **None of these**: This option is incorrect as we have identified the mouth as the site.

**Final Answer**: The first site of carbohydrate digestion is the **mouth**.

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