Figure 6.2 Rate of an enzyme-catalyzed reaction as a function of varying reactant concentration, with the concentration of enzyme constant.
-For the enzyme-catalyzed reaction shown in Figure 6.2, which of these treatments will cause the greatest increase in the rate of the reaction, if the initial reactant concentration is 1.0 micromolar?
A) doubling the activation energy needed
B) cooling the reaction by 10°C
C) doubling the concentration of the reactants to 2.0 micromolar
D) doubling the enzyme concentration
E) increasing the concentration of reactants to 10.0 micromolar, while reducing the concentration of enzyme by 1/2

Question

Figure 6.2 Rate of an enzyme-catalyzed reaction as a function of varying reactant concentration, with the concentration of enzyme constant.
-For the enzyme-catalyzed reaction shown in Figure 6.2, which of these treatments will cause the greatest increase in the rate of the reaction, if the initial reactant concentration is 1.0 micromolar?
A) doubling the activation energy needed 
B) cooling the reaction by 10°C 
C) doubling the concentration of the reactants to 2.0 micromolar 
D) doubling the enzyme concentration 
E) increasing the concentration of reactants to 10.0 micromolar, while reducing the concentration of enzyme by 1/2

Quizplus · Accepted Answer

The greatest increase in the rate of the reaction would be achieved by doubling the enzyme concentration. This would increase the number of enzyme-substrate complexes formed and thus increase the rate of the reaction. Changing the activation energy or cooling the reaction would both decrease the rate of the reaction. Doubling the concentration of the reactants would increase the rate of the reaction, but not as much as doubling the enzyme concentration. Increasing the concentration of reactants while decreasing the concentration of enzyme would likely decrease the rate of the reaction, as there would be fewer enzyme-substrate complexes formed. Therefore, D is the best choice.

Figure 62 Rate of an Enzyme-Catalyzed Reaction as a Function of of Varying