Chemical breakdown of starch starts with

Options

A. Salivary amylase
B. Pancreatic amylase
C. Amylopsin
D. Both (2) and (3)

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the initial stage of the chemical breakdown of starch. We need to identify where this process begins in the digestive system.

2. **Identifying Starch**: Starch is a complex carbohydrate that needs to be broken down into simpler sugars for absorption in the body.

3. **Location of Breakdown**: The breakdown of starch begins in the mouth, specifically in the buccal cavity.

4. **Role of Saliva**: Saliva, produced by three pairs of salivary glands (parotid, submandibular, and sublingual), contains enzymes that aid in digestion.

5. **Key Enzyme Involved**: The primary enzyme responsible for the breakdown of starch in saliva is salivary amylase. This enzyme starts the process of converting starch into simpler sugars.

6. **Conditions for Action**: Salivary amylase works optimally at a pH of around 6.8, which is the typical pH of saliva.

7. **Extent of Breakdown**: Approximately 30% of starch is digested in the buccal cavity before the food is swallowed and further digested in the stomach and intestines.

8. **Conclusion**: Based on the information gathered, the answer to the question is that the chemical breakdown of starch starts with **A. Salivary amylase**.

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