What is common among amylase, rennin and trypsin?

Options

A. These are produced in stomach
B. These act at a pH lower than 7
C. These all are proteins
D. These all are proteloytic enzymes

Answer

### Step-by-Step Solution:

1. **Identify the Enzymes**: The question asks about amylase, rennin, and trypsin. We need to first understand what these enzymes are and their functions.
- **Amylase**: An enzyme that breaks down starch into sugars (disaccharides). It is produced in the salivary glands and pancreas.
- **Rennin**: An enzyme that curdles milk by converting casein into para-casein. It is primarily found in infants and is produced in the stomach.
- **Trypsin**: A proteolytic enzyme produced in the pancreas that breaks down proteins into peptides.

2. **Common Characteristics**: Now, we need to find what is common among these three enzymes.
- **Proteins**: All three enzymes are proteins. This is a fundamental characteristic of enzymes, as they are biological catalysts made of amino acids.

3. **Functionality**: While they have different specific functions (amylase acts on starch, rennin on casein, and trypsin on proteins), they all serve as enzymes in the digestive process.

4. **Conclusion**: The commonality among amylase, rennin, and trypsin is that they are all enzymes and they are all proteins.

### Final Answer:
Amylase, rennin, and trypsin are all enzymes and they are all proteins.

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