Enzyme

Enzymes are macromolecular biological catalysts. They accelerate or catalyze chemical reactions. At the beginning of the process, the molecules are calle substrates and the enzyme converts these into different molecules, called products. Like all catalysts, enzymes increase the rate of a reaction by lowering its activation energy. Some even can make their conversion of substrate to product occur many millions of times faster, which allows a reaction that would otherwise take millions of years to occur in millioseconds. The set of enzymes made in a cell determines which metabolic pathways occur in that cell.

#Biology