Which is not correct ?

Options

A. All enzymes are biocatalysts
B. All proteins are enzymes
C. All enzymes are proteins
D. All enzymes are thermolabile.

Explanation

To determine which statement is not correct regarding enzymes, we will analyze each of the four statements provided:

1. **All enzymes are biocatalysts.**
- This statement is correct. Enzymes are indeed biocatalysts that facilitate biochemical reactions by lowering the activation energy required for the reaction to occur.

2. **All proteins are enzymes.**
- This statement is incorrect. While all enzymes are proteins, not all proteins function as enzymes. There are various types of proteins, such as structural proteins, transport proteins, and storage proteins, which do not have enzymatic activity.

3. **All enzymes are proteins.**
- This statement is correct. Enzymes are a specific type of protein that catalyzes biochemical reactions.

4. **All enzymes are thermolabile.**
- This statement is also correct. Enzymes are sensitive to temperature changes; they can denature and lose their functional shape at high temperatures, which affects their activity.

**Conclusion:**
The incorrect statement among the four provided is the second one: "All proteins are enzymes."