False-colour transmission electron micrograph of a section through a single dictyosome forming part of the Golgi apparatus in a mammalian cell. The dictyosome is the stack of paired membranes (green with red outlines) curving across the centre of the image. Dictyosomes act as a sorting office, packaging the protein products of the endoplasmic reticulum & directing them to their destination. Protein enters the dictyosome at one end of the stack (the forming face) and exits at the other end (the maturing face) wrapped in small spherical vesicles (small green shapes). The larger red sphere near the top is a mitochondrion. Magnification: x31,800 at 6x4.5cm size.