This document discusses enzyme induction and inhibition. It defines enzymes as biological catalysts that speed up reactions without being permanently altered. Enzyme activity can be altered by small molecules binding to the active site or other sites. Inhibitors reduce enzymatic reaction rates by blocking the active site without destroying enzymes, and can be reversible or irreversible. Inhibitors are classified as competitive, non-competitive, uncompetitive, or mixed based on whether they bind to the active site or other sites and how they impact substrate binding and catalysis. Enzyme induction increases enzyme production and activity through a homeostatic regulatory mechanism, often by combining with a regulatory protein to increase gene expression.