A biocatalyst

Options

A. decreases the activation energy and decreases the energy yield
B. increase the activation energy and increases the energy yield
C. decreases the activation energy and has no effect on the energy yield
D. increases the energy yield and decreases the activation energy

Answer

To solve the question regarding the role of a biocatalyst, we will analyze the options provided and understand the concept of activation energy and energy yield.

### Step-by-Step Solution:

1. **Understanding Biocatalysts**:
- A biocatalyst is a substance that increases the rate of a chemical reaction without being consumed in the process. Enzymes are the most common examples of biocatalysts.

2. **Activation Energy**:
- Activation energy is the minimum energy required for a chemical reaction to occur. Biocatalysts work by lowering this activation energy, allowing reactions to proceed more quickly and efficiently.

3. **Energy Yield**:
- Energy yield refers to the amount of energy produced from a reaction. This is determined by the difference in energy between the reactants and the products, not by the pathway taken to get there.

4. **Analyzing the Options**:
- **Option A**: Decreases the activation energy and decreases the energy yield. (Incorrect, because while activation energy decreases, energy yield remains constant.)
- **Option B**: Increases the activation energy and increases the energy yield. (Incorrect, as biocatalysts do not increase activation energy.)
- **Option C**: Decreases the activation energy and has no effect on the energy yield. (Correct, as biocatalysts lower activation energy without changing the energy yield.)
- **Option D**: Increases the energy yield and decreases the activation energy. (Incorrect, as energy yield does not change.)

5. **Conclusion**:
- The correct answer is **Option C**: "decreases the activation energy and has no effect on the energy yield."