Fluid Mosaic Model of Cell Membrane
| Part in Cell Membrane | Structure | Function | Part in Model |
| Phospholipid bilayer | Hydrophilic heads (polar) and hydrophobic tails (unsaturated fatty acids) | Make a continuous boundary between the cell and its environment, keeping most molecules out but allowing small ones in | |
| Cholesterol | Lipid with low melting temp | Maintains fluidity, especially when the cell is at low temperatures | |
| Integral Proteins | Protein that is imbedded inside the cell membrane either partially or completely. Can have both hydrophobic and hydrophilic parts. | Move items in and out of the cell using passive or active passageways; Enzymatic reactions inside the cell; Signal transduction convey signals from the outside of the cell to the inside, functioning like a light switch; Intercellular joining of cells to make tissues; Recognition by immune system to recognize what is self and not self | |
| Peripheral Proteins | Protein on the outside of membrane stuck in hydrophilic heads | Cytoskeletal fibers that allow cells to bind to one another or to a substrate | |
| Carbohydrate-proteins | A glycoprotein- carbohydrate attached to a protein | Recognition glycoproteins allow immune system to recognize what is self and not self; Cellular communication | |
| Small particles such as O2 and CO2 | Small, non-polar molecules that fit in between polar heads and are soluble in hydrophobic tails | Particles get into cell to be used for cellular respiration, photosynthesis and other metabolic processes |