Enzymes are biological catalysts that speed up chemical reactions and are inexhaustible. They can increase the rate at which reactions occur by up to a factor of 10^19. The material that is being acted on by the enzyme is called a substrate. Enzymes work because they can bind to the transition state better than the substrate, which lowers the activation energy causing the speed of a reaction to accelerate. The enzyme combines with a substrate at the enzymes active site which creates the enzyme substrate complex. This is where catalysis takes place. When the reaction is complete, the complex dissociates. After the complex dissociates the enzyme is unchanged and as a result can move on to catalyze another reaction. Even though enzymes speed up
