A storage and mixing system for pasty two-component polymethyl methacrylate bone cements comprises a tubular cartridge having a cylindrical inner chamber, a dispensing plunger that is axially displaceable in the inner chamber of the cartridge, a partition disposed axially in the tubular cartridge, and a cartridge head which closes one end of the tubular cartridge. The cartridge head has a slot-shaped opening, wherein the partition protrudes from the inner chamber of the cartridge through the slot-shaped opening of the cartridge head, wherein the partition divides the cylindrical inner chamber of the cartridge bounded by the dispensing plunger and the cartridge head into two cavities that are spatially separated from one another. A first pasty cement component is present in the first cavity and a second pasty cement component is present in the separate second cavity, wherein the partition is removable through the slot-shaped opening of the cartridge head so that the two separate cavities are connected to one another after the partition is removed.