`K_(m)` value is dependent upon

Options

A. Temperature
B. Substrate concentration
C. Enzyme concentration
D. All the above.

Answer

To determine what the \( K_m \) value is dependent upon, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition of \( K_m \)**:
- The \( K_m \) value, also known as the Michaelis-Menten constant, is defined as the substrate concentration at which the reaction velocity is half of the maximum velocity (\( V_{max} \)) of an enzyme-catalyzed reaction.

2. **Identify Factors Affecting \( K_m \)**:
- \( K_m \) reflects the affinity of the enzyme for its substrate. A low \( K_m \) indicates high affinity, while a high \( K_m \) indicates low affinity.
- It is important to note that \( K_m \) is not influenced by the concentration of the substrate or the concentration of the enzyme.

3. **Consider External Factors**:
- The \( K_m \) value can be affected by environmental conditions such as temperature and pH. These factors can influence enzyme activity and stability, thereby affecting the \( K_m \) indirectly.

4. **Evaluate the Given Options**:
- The options provided are:
- Temperature
- Substrate concentration
- Enzyme concentration
- All of the above
- Since \( K_m \) is independent of substrate and enzyme concentration, the only factor from the options that affects \( K_m \) is temperature.

5. **Conclusion**:
- Therefore, the correct answer is that the \( K_m \) value is dependent upon temperature.

### Final Answer:
The \( K_m \) value is dependent upon **temperature**.

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