In biosynthetic pathways, small molecules are assembled into large molecules-for example, simple sugars are assembled into complex carbohydrates. In degradative pathways, large molecules such as carbohydrates, lipids, and proteins are broken down to form products of lower energy. Released energy can be used for cellular work. Enzymes A. Characteristics of Enzymes 1. Enzymes can be reused.
Enzyme actions are reversible.
The active site is a crevice where the substrate binds to the enzyme during a reaction. Enzymes increase the rate of a reaction by lowering the activation energy through ex-ensive bonding of substrate at the active site. C. Effects of Temperature and pH on Enzymes 1. D. Control of Enzyme Activity 1. ATP is composed of adenine, ribose, and three phosphate groups.