Fat cells. Coloured scanning electron micrograph (SEM) of a freeze-fractured sample of adipose tissue, consisting of fat-storing cells (adipocytes) supported by connective tissue (grey strands). Almost the entire volume of each fat cell consists of a single lipid (fat or oil) droplet (orange). Adipose tissue forms an insulating layer under the skin, storing energy in the form of fat, usually obtained from excess food. Magnification: x500 when printed at 10 centimetres high.