The liver, an organ found in all vertebrates, is the largest organ in the human body. It is a spongy, reddish browh gland that lies just below the diaphragm in the abdominal cavity. It serves to metabolize Carbohydrates and store them as glycogen; metabolize lipids (fats, including cholesterol and certain vitamins) and protein manufacture a digestive fluid, bile, filter impurities and toxic material from the blood; produce blood-clotting factors , and destroy old, worn-out red blood cells . Two large lobes, the right and the left, make up most of the liver; attached to the right lobe are the smaller quadrate and caudate lobes. The lobes are made up of lobules - six sided cells arranged in sheets one cell thick - that are closely arranged around blood vessels, blue ducts, lymp vessels, and nerves. Certain reticuloendothelial cells (Kupffer cells) line these lobules and play a role in immunity. Approximately three sides of each cell are in contact with a blood vessel , and there are
