Question

the activity of an enzyme was examined in the laboratory as it catalyzed the formation of a product molecule, b, from a substrate, a. this reaction was carried out in an aqueous solution consisting of water and copper sulfate at a ph of 7. while attempting to repeat the experiment, a biochemist uses a solution of pure distilled water (ph = 7) and observes that the rate of formation of b has decreased dramatically. which is a possible explanation for this result? the enzyme needs the presence of a buffer to function. the enzymes optimal activity is not at ph 7. the enzyme needs copper ions to act as cofactors for optimal enzyme activity. b is unstable and cannot be measured. sulfate ions inhibit binding of a to the enzymes active site.

Explanation:

Enzymes often require specific co - factors for optimal activity. Copper ions can act as co - factors for some enzymes. In this case, the decrease in product formation (B) when copper sulfate is added may be because the enzyme needs copper ions as co - factors for optimal activity. Without copper ions in the right form or concentration, the enzyme's activity is reduced.

Answer:

The enzyme needs copper ions to act as cofactors for optimal enzyme activity.