Answer: The enzyme denatures with changes in pH
Explanation: Enzyme activity is highly dependent on the pH level of the environment. Enzymes have an optimal pH at which they function most effectively. Deviating from this optimal pH, either in the acidic or alkaline direction, can disrupt the enzyme's structure (denaturation) and reduce its activity. In the given scenario, as the pH deviates from the optimal value, the enzyme denatures, leading to a decrease in enzyme activity on either side of pH 8.