Almost all eukaryotic cells, plant and animal, contain a specialized part of the internal membrane system called the Golgi apparatus, named after Camillo Golgi, the Italian physician who discovered it in 1898. Characteristically, a golgi apparatus is composed of regions of stacked cisternae lacking membrane bound ribosomes. The major function of these organelles is to process and export of materials from cells and to make lysosomes.
This can be seen very clearly in secretory cells where proteins and other materials are brought to the Golgi from their primary points of synthesis, are modified in the apparatus and are then pinched off into secretory vacuoles from the edges of the flattened disks. As with the vesicles from the ER, secretion of the contents of the vacuoles takes place when the vacuoles fuse with the plasma membrane.
Golgi apparatus consisting of flattened cisternae and some secretory vesicles.