* Absorbed compounds are carried by the blood to the liver, which plays a central role in metabolism. Most absorbed compounds are broken down for energy, stored, or used to build larger compounds. * Excess carbohydrates and proteins are converted to fat and stored in adipose tissue. * The liver detoxifies dangerous substances (alcohol, NH3), and stores fat-soluble vitamins (A, D) and glucose (as glycogen). * Between meals, the liver provides the brain with glucose by breaki