Compartmentation

Compartmentalization refers to the elaborate sub division of eukaryotic cell into individual, functionally distinct, membrane enclosed compartments. Each compartment, known as an organelles contains its own characteristic set of enzymes specialized molecules and complex distributions systems transport specific products from one compartment to another while allowing segregation of activities..

These compartments will occupy ~ half of the cell volume. The cytoplasm refers to the cells cytosol plus all the organelles within the cell. Intercellular membrane systems form enclosed compartments that are separate from the cytosol, and thus creating functionally specialised aqueous spaces within the cell

Each organelle is surrounded by a lipid bilayer, impermeable to most hydrophilic molecules and so the membrane of each organelle must contain transport proteins such as carrier proteins, protein channels and pores to import and export specific metabolites into the cell. The mechanisms by which these are transported into and out of the cell make the organelle unique and are determined by its function. 

Some compartments within Eukaryotic cells include; the nucleus, chloroplasts, ribosomes, endoplasmic reticulum, golgi apparatus and mitochondria .