False-colour scanning electron micrograph (SEM) of the cell structure within a lobule of the liver. Hepatic cells (brown) surround sinusoids (blue channels) in a three-dimensional network. Blood (red) flows through these sinusoids to link up to a central vein. In this process of blood flow, specialized liver cells clean the blood of microorganisms, toxins, aged cells, and debris. Bile formed by the liver cells is released into tiny bile capillaries (cholangioles, green). Bile enters the gall bladder to be used for digestive purposes. The liver also synthesizes Vitamin A. Magnification: ×300 at 6×7cm size. Magnification: ×460 at 4×5 inch size. Cover credit: PROF. P. MOTTA / DEPT. OF ANATOMY / UNIVERSITY “LA SAPIENZA”, ROME / SCIENCE PHOTO LIBRARY.