The endomembrane system is the system of internal membranes within eukaryotic cells that divide the cell into functional and structural compartments, or organelles. Prokaryotes do not have an endomembrane system and thus lack most organelles.
The endomembrane system also provides a transport system, for moving molecules through the interior of the cell, as well as interactive surfaces for lipid and protein synthesis. The membranes that make up the endomembrane system are made of a lipid bilayer, with proteins attached to either side or traversing them.
The following organelles are part of the endomembrane system: