A group of proteins, in living cells, which catalyses chemical reactions, is called ............

Explanation

**Step-by-Step Solution:**

1. **Identify the Group of Proteins**: The question asks about a specific group of proteins in living cells that play a crucial role in chemical reactions.

2. **Understanding the Function**: These proteins are known for their ability to catalyze, which means they speed up chemical reactions without being consumed in the process.

3. **Definition of Catalysis**: Catalysis is the process of increasing the rate of a chemical reaction by providing an alternative pathway with a lower activation energy.

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