Vesicles transport materials within a cell. Vesicles are constantly forming, membrane-wrapped containers that transport things like protein through a cell.
Vesicles that are artificially prepared are called liposomes. Naturally prepared vesicles are those made during exocytosis, endocytosis and phagocytosis. The membrane that encloses a vesicle is similar to the plasma membrane, and plasma membranes and vesicles can fuse together, making it possible to release the contents of the vesicle outside the cell.
Vesicles have various job functions. They aid in metabolism and enzyme storage and help control the balance inside and outside a cell. When vesicles malfunction, sometimes serious or fatal conditions may occur like diabetes and epilepsy.