ANSWER:
Changes in pH not only affects the shape of an enzyme but also changes the shape or charge properties of the substrate
Step-by-step explanation:
Changes in pH may not just change the shape of an enzyme but it may further alter the appearance or charge properties of the substrate so that either the substrate cannot connect to the existing site or it cannot undergo catalysis. In common, the enzyme have a pH optimum. Despite, the optimum is not identical for every enzyme.