Enzymes are able to accelerate a reaction because

Options

A. Reacting substances are brought into highly specific relations with each other
B. Energy is added to the system
C. Molecules of the reactants are speeded up so that random encounters are more
D. Products of the reaction are removed simultaneously

Answer

To answer the question "Enzymes are able to accelerate a reaction because," we need to analyze the options provided and understand the role of enzymes in biochemical reactions.

### Step-by-Step Solution:

1. **Understanding Enzymes**: Enzymes are biological catalysts that speed up chemical reactions in living organisms. They do this by lowering the activation energy required for the reaction to occur.

2. **Analyzing the Options**:
- **Option 1**: "Reacting substances are brought into highly specific relationship with each other."
- This statement is partially true as enzymes do facilitate the proper orientation of substrates, but it does not fully explain how they accelerate reactions.
- **Option 2**: "Energy is added to the system."
- This is the correct answer. Enzymes lower the activation energy barrier, effectively allowing the reaction to proceed faster without adding external energy.
- **Option 3**: "Molecules of the reactant are speeded up so that random encounters are more."
- This is incorrect because enzymes do not speed up the molecules themselves; they provide an alternative pathway for the reaction.
- **Option 4**: "Products of the reaction are removed simultaneously."
- This statement is also incorrect as it does not directly relate to how enzymes function to accelerate reactions.

3. **Conclusion**: The correct answer is **Option 2**: "Energy is added to the system." Enzymes accelerate reactions by lowering the activation energy, which effectively increases the rate of reaction.

### Final Answer:
Enzymes are able to accelerate a reaction because energy is added to the system.

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