[Campbell Biology P.204] Which statement accurately describes the effect of an enzyme on a b... | Practice Question

Which statement accurately describes the effect of an enzyme on a biochemical reaction based on the provided text and Figure 8.14?

  • A: Enzymes decrease the activation energy (EA) of a reaction, thereby speeding it up.
  • B: Enzymes increase the free-energy change (ΔG) of a reaction, making it more favorable.
  • C: Enzymes increase the total free energy of the products relative to the reactants.
  • D: Enzymes make endergonic reactions exergonic.

Explanation

Figure 8.14 and the accompanying text explicitly state that enzymes speed up reactions by reducing the activation energy EA but do not affect the free-energy change ΔG for a reaction. This means they do not alter the overall energy difference between reactants and products, nor do they make an endergonic reaction exergonic.