How does the Michaelis-Menten constant (K_m) relate to enzyme-substrate affinity and reaction velocity?

• A. A high K_m indicates a high affinity of the enzyme for the substrate and results in a higher reaction velocity.
• B. A low K_m indicates a low affinity of the enzyme for the substrate and results in a higher reaction velocity.
• C. A high K_m indicates a low affinity of the enzyme for the substrate and requires a higher substrate concentration to reach half of the maximum reaction velocity (V_max).
• D. K_m has no relationship with enzyme-substrate affinity or reaction velocity.

Answer: (C)