Endocytosis is a general term for the process by which very large particles of material are enveloped in a plasma membrane and moved into the cell as vesicles or vacuoles. No trapped material crosses the membrane, but remains on the other side of the original membrane, even when the vacuole is inside the cell. Exocytosis is the export of large quantities of material from the cell. Vesicles containing the material to be exported fuse with the plasma membrane, releasing the contents into the environment around the cell (Simon, 2015, p..