A-LevelBiologyEnzymesFeb/Mar 2025Paper 1 Q151 Mark
Succinic dehydrogenase is an enzyme that catalyses the conversion of succinate to fumarate in aerobic respiration. Malonate is a reversible inhibitor of succinic dehydrogenase. Malonate reduces the enzyme’s activity by binding to its active site. Malonate and succinate cannot bind to the active site at the same time. Which statement describes the effect of malonate on the activity of succinic dehydrogenase?
AIn the presence of malonate, Vmax can still be reached if the concentration of succinate is increased.
BMalonate has no effect on the Km.
CIn the presence of malonate, Vmax can still be reached if the concentration of fumarate is increased.
DMalonate decreases the Km.
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