It works like a factory assembly.The endoplasmic reticulum is like a shipping dept shipping the products of reactions that occur within the cell to the Golgi apparatus.In the Golgi materials produced by the cell are packaged in the Vesicles,small membrane enclosed sacs.The Vesicles are then mailed to other organelles or to the cell membrane for export.The cell membrane contains 'customs officers' (called CHANNELS) who allow secretions of the contents from cell.Secreted substances are then available for other cells or organs