The function of enzymes in the living system is to

Options

A. Transport oxygen
B. Provide immunity
C. Catalyse biochemical reactions
D. Provide energy

Answer

**Step-by-Step Solution:**

1. **Understanding Enzymes:**
- Enzymes are complex organic molecules primarily composed of proteins. They play a crucial role in biological systems.

2. **Function of Enzymes:**
- The primary function of enzymes is to catalyze biochemical reactions. This means they speed up the rate of these reactions, making them occur more efficiently.

3. **Mechanism of Action:**
- Enzymes increase the rate of biochemical reactions by lowering the activation energy required for the reaction to proceed. This makes it easier for the reactants to convert into products.

4. **Role in Metabolism:**
- Enzymes are involved in nearly all metabolic processes within living organisms. Each metabolic reaction is typically facilitated by a specific enzyme.

5. **Elimination of Incorrect Options:**
- Option A: Transport oxygen - This is the function of hemoglobin, not enzymes.
- Option B: Provide immunity - Immunity is provided by immune cells (like T cells and B cells), not enzymes.
- Option D: Provide energy - Energy is derived from macromolecules (like carbohydrates and lipids), not directly from enzymes.

6. **Conclusion:**
- The correct answer to the question regarding the function of enzymes in living systems is that they catalyze biochemical reactions.

**Final Answer:**
The function of enzymes in the living system is to catalyze biochemical reactions.

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