Which of the following statements about enzymes is true? ANSWER Enzymes speed up the rate of the reaction without changing the ΔG for the reaction. Enzymes increase the rate of a reaction by raising the activation energy for reactions. Enzymes react with their substrate (form chemical bonds), forming an enzyme-substrate complex, which irreversibly alters the enzyme. All of the listed responses are correct. The more heat that is added to a reaction, the faster the enzymes will function.

Enzymes speed up the rate of the reaction without changing the ΔG for the reaction.

Explanation: Enzymes speed up the rate of the reaction without changing the ΔG for the reaction.

Enzyme (E) binds to the substrate (S) to form an enzyme–substrate complex (ES) products are formed at the end of the reaction but however, the enzyme remains unaltered, it can still bind to another substrate and/or can be reused as many times as possible.

Enzymes accelerate the rate of reaction by decreasing the activation energy.

Temperature affects the activity of enzymes, increasing it to reach a limit, which corresponds to the optimal enzyme activity. If the temperature goes beyond this maximum limit, enzymatic activity declines. The optimal temperature for most animal enzymes is about 37°C. The inactivating effect of temperature is due to protein denature.