Of the starch consumed, about 30% is hydrolysed by

Options

A. Gastric amylase
B. Salivary amylase
C. Amylase of bile
D. Microbes of caecum

Answer

To solve the question "Of the starch consumed, about 30% is hydrolyzed by which enzyme?", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Starch Hydrolysis**:
- Starch is a carbohydrate made up of glucose units linked by glycosidic bonds. When starch is consumed, it needs to be broken down into simpler sugars (like glucose) for absorption.

2. **Identifying Enzymes Involved**:
- The question provides options: salivary amylase, gastric amylase, amylase of bile, and microbes of the cecum. We need to determine which of these is responsible for hydrolyzing starch.

3. **Role of Salivary Amylase**:
- Salivary amylase is an enzyme present in saliva that begins the digestion of starch in the mouth. It hydrolyzes starch into smaller oligosaccharides and maltose.

4. **Percentage of Hydrolysis**:
- According to the information provided, about 30% of the starch consumed is hydrolyzed by salivary amylase during the initial phase of digestion in the mouth.

5. **Other Enzymes**:
- The remaining 70% of starch is hydrolyzed by pancreatic amylase in the small intestine. Gastric amylase does not play a significant role in starch digestion, and bile does not contain amylase. The microbes in the cecum are involved in the digestion of cellulose, not starch.

6. **Conclusion**:
- Therefore, the correct answer to the question is that about 30% of the starch consumed is hydrolyzed by **salivary amylase**.

### Final Answer:
**Salivary Amylase**

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