Which of the following factor(s) do(es) not affect enzyme activity ?
A. Temperature
B. pH
C. Enzyme concentration
D. Product concentration
E. Substrate concentration
F. Activation energy

Options

A. C only
B. C & D
C. D only
D. F only

Answer

To determine which factor(s) do(es) not affect enzyme activity, we need to analyze each option provided in the question:

1. **Temperature (A)**: Enzymes are proteins that can be denatured by high temperatures, which affects their activity. Therefore, temperature does influence enzyme activity.

2. **pH (B)**: Each enzyme has an optimal pH range in which it functions best. Deviations from this pH can lead to decreased enzyme activity or denaturation. Thus, pH also affects enzyme activity.

3. **Enzyme Concentration (C)**: The concentration of enzymes directly influences the rate of reaction. More enzymes mean more active sites available for substrates, leading to increased reaction rates. Hence, enzyme concentration affects enzyme activity.

4. **Product Concentration (D)**: The concentration of products can influence the reaction rate through feedback mechanisms. It can either inhibit or enhance enzyme activity, depending on the context. Therefore, product concentration does affect enzyme activity.

5. **Substrate Concentration (E)**: Initially, as substrate concentration increases, enzyme activity increases until all active sites are occupied. Beyond that point, adding more substrate does not increase activity. Thus, substrate concentration affects enzyme activity.

6. **Activation Energy (F)**: Activation energy is the energy required for a reaction to occur. Enzymes lower the activation energy required for reactions but do not influence their own activity based on activation energy. Therefore, activation energy does not affect enzyme activity.

Based on this analysis, the only factor that does not affect enzyme activity is:

**Answer: F. Activation energy**

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