The correct statement about ptyalin and pancreatic amylase is :

Options

A. Ptyalin breaks down only uncooked starch in acidic medium while pancreatic amylase breaks down only uncooked starch in alkaline medium.
B. Ptyalin breaks down only cooked starch in alkaline medium while pancreatic amylase breaks down only uncooked starch in acidic medium.
C. Ptyalin breaks down only uncooked starch in acidic medium while pancreatic amylase breaks down only cooked starch in alkaline medium.
D. Ptyalin breaks down only cooked starch in acidic medium while pancreatic amylase breaks down only uncooked starch in alkaline medium.

Answer

To solve the question regarding the correct statement about ptyalin and pancreatic amylase, we need to analyze the functions and characteristics of both enzymes.

### Step-by-Step Solution:

1. **Identify the Enzymes**:
- **Ptyalin**: Also known as salivary amylase, this enzyme is produced in the saliva.
- **Pancreatic Amylase**: This enzyme is produced in the pancreas and released into the small intestine.

2. **Function of Ptyalin**:
- Ptyalin breaks down starch into simpler sugars (like maltose) primarily in an **acidic medium**.
- It is effective on **uncooked starch**. Cooked starch is more readily digestible, but ptyalin specifically targets starch that has not been gelatinized through cooking.

3. **Function of Pancreatic Amylase**:
- Pancreatic amylase also breaks down starch into simpler sugars, but it operates in an **alkaline medium** (basic environment).
- It is effective on **uncooked starch** as well.

4. **Evaluate the Statements**:
- **Statement 1**: Incorrect. Ptyalin does not break down cooked starch; it acts on uncooked starch.
- **Statement 2**: Incorrect. Ptyalin does not work in an alkaline medium.
- **Statement 3**: Incorrect. Ptyalin does not break down cooked starch; it works on uncooked starch in an acidic medium.
- **Statement 4**: Correct. Ptyalin breaks down uncooked starch in an acidic medium, while pancreatic amylase breaks down uncooked starch in an alkaline medium.

5. **Conclusion**:
- The correct statement about ptyalin and pancreatic amylase is that **Ptyalin breaks down uncooked starch in an acidic medium, while pancreatic amylase breaks down uncooked starch in an alkaline medium**.

### Final Answer:
The correct statement is: **Ptyalin breaks down uncooked starch in an acidic medium, while pancreatic amylase breaks down uncooked starch in an alkaline medium.**