Which is not a hydrolase?

Options

A. Protease
B. Dehydrogenase
C. Sucrase
D. Amylase.

Answer

To determine which option is not a hydrolase, we can follow these steps:

### Step 1: Understand what hydrolases are
Hydrolases are a class of enzymes that catalyze the cleavage of covalent bonds through the addition of water. This process is known as hydrolysis.

### Step 2: Analyze the options
The options given are:
1. Protease
2. Dehydrogenase
3. Sucrase
4. Amylase

### Step 3: Identify the function of each enzyme
- **Protease**: This enzyme breaks down proteins by hydrolyzing peptide bonds, thus it is a hydrolase.
- **Dehydrogenase**: This enzyme is involved in oxidation-reduction reactions, specifically it removes hydrogen from a substrate and does not use water to cleave bonds. Therefore, it is not a hydrolase.
- **Sucrase**: This enzyme catalyzes the hydrolysis of sucrose into glucose and fructose, making it a hydrolase.
- **Amylase**: This enzyme breaks down starch into sugars through hydrolysis, so it is also a hydrolase.

### Step 4: Conclusion
From the analysis, the enzyme that is not a hydrolase is **Dehydrogenase**.

### Final Answer
The correct answer is **Dehydrogenase**.

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