Empty fat cells. Coloured scanning electron micrograph (SEM) of the adipocytes (fat cells) that make up adipose connective tissue. The honeycomb structure of the cell membranes is seen here. The lipid (fat) deposits of the cells (their major component) has been removed. Fat cells are amongst the largest cells in the human body. They form a thick insulating layer under the skin. Magnification: x260 when printed 10 centimetres wide.