All cell membranes have the same basic structure, composed of lipids, proteins and carbohydrates.
- The arrangement of molecules in the membranes are described by the fluid mosaic model.
- Essentially, phospholipid molecules form a bilayer - a double layer.
- This is known as being "fluid" due to the constant movement of the phospholipids.
The "mosaic" comes from the arrangement of proteins, as they are scattered throughout the phospholipid bilayer.
- The proteins are also channel proteins and carrier proteins - these are transport molecules.
- They allow ions and large molecules to pass through the phospholipid bilayer.