D. Non-protein compounds that function in the reaction mechanism for some enzymes. A. Enzyme activity decreases below its optimum, since reactants no longer have enough thermal energy to achieve activation energy. B. Enzyme activity decreases above a temperature optimum, since protein structure is destabilized. The electrical properties of some amino acid side chains are affected by pH, so most enzymes have a pH optimum. All of the above are true.
Many enzymes consist of two or more subunits that each carry out the same reaction.
Often, the binding of substrate to the active site of one subunit increases the rate of binding to the other active sites. C. allosteric inhibition. D. zymogen activation. A. Competitive inhibition. B. Non-competitive inhibition.