Liver is the glandular organ that stores and metabolizes nutrients, detoxifies, and produces bile salts. Liver is the largest organ of human body. The study of anatomy and functions of the liver is known as Liver Biology. Liver consists of two major lobes, the right lobe and the left lobe, and two smaller lobes, the caudate lobe and the quadrate lobe. Lying under the right lobe is the gallbladder, a muscular sac that is anatomically and physiologically associated with the liver. Emerging from the gallbladder is the cystic duct. The lobes contain liver cells (hepatocytes), which secrete bile, an alkaline , yellow-green liquid that is composed of water, bile salts, and several other substances. Bile is delivered to the duodenum, the first portion of the small intestine, where the bile salts emulsify lipids ; that is, break down large lipid globules into small droplets, in order to increase the efficiency of lipid digestion and absorption by the small intestine. In addition to producing bile for the emulsification of dietary lipids, the liver also plays an important role in the maintenance of normal blood glucose concentration, inactivation of toxins, synthesis of plasma proteins , and the metabolism of carbohydrates , fats, and proteins.