Question

Inhibitor molecules can block an enzyme's activity. Some inhibitors, called competitive inhibitors, compete directly with the substrate for the enzyme's active site. What effect will such inhibitors have on the reaction?

Choose one:
A. They will decrease the Vmax of the reaction.
B. They will decrease the KM of the reaction.
C. They will have no effect on the Vmax of the reaction.
D. They will increase the Vmax of the reaction.
E. They will have an irreversible effect on the reaction.

Answer 1

Competitive inhibitors compete with the substrate for the active site of an enzyme, but they do not affect Vmax since the maximum rate can still be achieved if substrate concentration is sufficiently high. Option C is correct.

Step-by-step explanation:

Competitive inhibitors compete directly with the substrate for the enzyme's active site which can alter the rate of the reaction.

The effect of such inhibitors is that they will have no effect on the Vmax of the reaction, because the reaction can still proceed at the maximum rate if the substrate concentration is high enough to outcompete the inhibitors. This reflects the nature of competitive inhibitors as they can be outcompeted by an excess of substrate. Therefore, the correct option is C.