Enzymes which catalyse intra molecular rearrangement are kept under

Options

A. Isomerases
B. Oxidoreductases
C. Hydralases
D. None of the above

Answer

To answer the question "Enzymes which catalyse intramolecular rearrangement are kept under," we will analyze the options provided and determine the correct classification of the enzymes.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about enzymes that catalyze intramolecular rearrangements. This means we are looking for a class of enzymes that facilitate the rearrangement of atoms within a single molecule.

2. **Evaluating the Options**:
- **Option A: Isomerase**: Isomerases are enzymes that catalyze the conversion of a molecule into one of its isomers. This includes intramolecular rearrangements, which result in the formation of optical isomers, geometrical isomers, or positional isomers. Thus, this option is likely correct.

- **Option B: Oxyreductase**: Oxyreductases are enzymes that catalyze oxidation-reduction reactions. They do not specifically facilitate intramolecular rearrangements, so this option is incorrect.

- **Option C: Hydrolysis**: Hydrolytic enzymes catalyze the breakdown of complex molecules into simpler ones, often using water. This process does not involve rearranging the atoms within a molecule but rather breaking them apart, making this option incorrect.

- **Option D: None of the above**: Since we have identified that isomerases do catalyze intramolecular rearrangements, this option is also incorrect.

3. **Conclusion**: Based on the analysis, the correct classification of enzymes that catalyze intramolecular rearrangements is **Isomerase**.

### Final Answer:
The correct answer is **Isomerase**.

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