Fluid Mosaic Model

The currently accepted model of the cell membrane is called the fluid mosaic model

Phospholipids can move within the bilayer, making the membrane fluid meaning they can change shape and flow.

The term 'mosaic' refers to the diverse collection of molecules that make up the membrane

The fluidity of the membrane allows for:

• Formation of vesicles

• Materials to be taken into cells by endocytosis or released by exocytosis

• Movement of transport proteins within/around the membrane

Membrane fluidity can be further regulated by the presence of cholesterol

1. Phospholipid bilayer shown with heads facing in opposite directions.

2. Phospholipids with labelled hydrophilic/phosphate head and hydrophobic/hydrocarbon tail​

3. Peripheral protein, shown as globular structure at the surface of the membrane.​

4. Integral protein shown as embedded globular structure.​

5. Glycoprotein shown as embedded globular structure with protruding carbohydrate (shown as a branching, antenna-like structure).​

6. Channel protein shown with a pore passing through it.​

7. Cholesterol shown in between adjacent phospholipids.​

8. Glycolipid (in green but unlabeled)​