Caption

Liver cell, coloured transmission electron micrograph (TEM). A healthy liver cell (hepatocyte) showing the wide range of organelles typical of hepatocytes. Liver cells commonly have two nuclei (large, round structures, light brown) meaning they contain double the usual number of chromosomes, a characteristic known as polyploidy. Liver cells require a large amount of energy and therefore contain large numbers of mitochondria (orange) which are the sites of respiration within the cell. Rough endoplasmic reticulum (RER, yellow lines) and glycogen granules (black dots), the storage form of glucose, can also be seen. Magnification: x73,300 when printed at 10 centimetres wide.