The Fluid Mosaic Model Structure
Think of cell membranes as a flexible sandwich made primarily of phospholipids arranged in a bilayer. Each phospholipid has a hydrophilic phosphate head (loves water) and hydrophobic fatty acid tails (hates water). When mixed with water, these clever molecules automatically arrange themselves with heads facing outward and tails tucked safely inside.
Intrinsic proteins are embedded right through the membrane, whilst extrinsic proteins sit on the surface like decorations. The positioning of these proteins depends entirely on their hydrophilic and hydrophobic regions - they naturally find their perfect spot.
It's called the "fluid mosaic" model because phospholipids and proteins can move around freely (fluid), creating a scattered, tile-like pattern (mosaic). Cholesterol molecules squeeze between phospholipids, acting like tiny regulators that keep the membrane at just the right consistency.
Key Point: The membrane's structure is self-organising - molecules arrange themselves based on whether they love or hate water!
