Liver peritoneum. Coloured scanning electron micrograph (SEM) of the peritoneal cells which form the peritoneum that covers the liver. These flattened serosal cells have many short hair-like microvilli. The cells secrete fluid derived from blood serum, which allows the liver to move smoothly within the abdomen. The protective peritoneum lines the whole of the abdominal cavity, which is important in this organ-packed part of the body. Magnification unknown.