The activity of certain macromolecules as catalysts within living systems is a central biological process. Macromolecules that act as catalysts are enzymes. Most, but not all, enzymes are proteins. A few ribonucleoprotein enzymes have been discovered in which the catalytic activity is in the RNA portion of the molecule rather than the protein part. Enzymes bind temporarily to one or more reactants and lower the activation energy of the reaction.
Enzyme concepts including mechanics, kinetics and regulation are centrally important for the new MCAT, in which biochemistry has such strong emphasis. To understand enzyme activity at the superior level you need to fully involve your general chemistry and organic chemistry. Beyond simple retention of information, try your best to embed your understanding of this material in all of its conceptual underpinnings from the rest of science.
Conceptual Vocabulary for Enzymes