Which of the following enzymes is not useful in the digestion of proteins

Options

A. Chymotrypsin
B. Pepsin
C. Trypsin
D. Lipase

Explanation

To determine which enzyme is not useful in the digestion of proteins, we need to analyze the functions of the given enzymes:

1. **Identify the enzymes listed in the question**:
- Chymotrypsin
- Pepsin
- Trypsin
- Lipase

2. **Understand the function of each enzyme**:
- **Chymotrypsin**: This enzyme is a protease that digests proteins in the small intestine. It breaks down protein molecules into smaller peptides.
- **Pepsin**: This enzyme is also a protease and is active in the stomach. It begins the process of protein digestion by breaking down proteins into smaller peptides.
- **Trypsin**: Another protease that functions in the small intestine, trypsin further digests proteins into smaller peptides and amino acids.
- **Lipase**: This enzyme is involved in the digestion of lipids (fats) rather than proteins. It breaks down fats into fatty acids and glycerol.

3. **Determine which enzyme is not useful in protein digestion**:
- From the analysis, we can see that chymotrypsin, pepsin, and trypsin are all involved in the digestion of proteins. However, lipase is not involved in protein digestion; instead, it is involved in lipid metabolism.

4. **Conclusion**:
- Therefore, the enzyme that is not useful in the digestion of proteins is **lipase**.

**Final Answer**: Lipase is the enzyme that is not useful in the digestion of proteins.

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