Cellular compartment

1 B io F actsheet September 1997 Number 4 Structure to function in eukaryotic cells The cell surface membrane and the membranes which form organelles in eukaryotic cells all have the same basic structure, known as the fluid mosaic model. Such membranes provide control of the entry and exit of substances into cells and organelles and such control is a result of the phospholipid bilayer and membrane proteins. In eukaryotic cells, such membranes divide the cytoplasm into multiple compartments (organelles). Organelles allow different functions to occur efficiently and simultaneously in different parts of the cell. For example, the outer double membrane of the mitochondrion separates out those reactions which occur in mitochondria from those in the general cytoplasm.