Light micrograph of a section through a liver lobule. Hepatocytes, the main functional cells of the liver, are arranged in units called lobules. Blood filters through a lobule to its central vein (white, lower centre), which drains blood into the hepatic vein. The functions of the liver include destroying old red blood cells, breaking down harmful waste products and toxins in the blood, and extracting useful nutrients from the blood to make and store proteins and other useful chemicals. Numerous capillaries, veins and arteries supply and remove blood. The structure of the liver tissue allows the blood to percolate through the tissue. At any one moment, the liver holds over 10 percent of the body's blood supply. Magnification: x100 when printed at 15cm wide.