Catechol is a chemical found in a number of fruits. Catechol can be oxidised to a quinone by the enzyme catechol oxidase. Catechol oxidase is inhibited by parahydroxybenzoic acid (PHBA), which is structurally similar to catechol. In the presence of PHBA, the Michaelis-Menten constant (Km) for catechol oxidase increases. How does PHBA inhibit catechol oxidase? 1 PHBA and catechol can both bind to the enzyme but not at the same time. 2 PHBA is a non-competitive inhibitor of catechol oxidase. 3 PHBA decreases the Vmax of the reaction.

Which statement describes an example of an extracellular enzyme?

Which row is correct for enzymes that catalyse reactions using the lock-and-key hypothesis?

Many flowers produce a sweet solution called nectar. Bees provided with nectar use enzyme Q to change the nectar into…

The enzyme telomerase repairs telomeres. It stops the telomeres from getting shorter each time a chromosome is replic…

The statements describe events during the mitotic cell cycle. 1 Chromosomes migrate to opposite poles of the spindle.…

Which statement about nitrogenous bases is correct?