Explain how mobile lipids and proteins form a membrane mosaic, and use evidence about protein placement to compare the Singer–Nicolson model with Davson–Danielli.
Draw a labelled diagram to show the fluid mosaic model of the plasma membrane.
a. two correctly orientated layers of phospholipids/phospholipid bilayer shown with heads facing in opposite directions
b. phospholipids shown with two parts labelled hydrophilic/phosphate head AND hydrophobic/hydrocarbon tail
c. protein (any) shown as a globular structure embedded in one/both layers of phospholipid
d. peripheral protein shown as globular structures at the surface of the membrane AND integral protein shown as embedded globular structures
e. glycoprotein shown as embedded globular structure with antenna-like carbohydrate protruding
OR
carbohydrate shown as branched/antenna-like structure attached either to a protein or to a phospholipid
OR
channel protein(s) shown with a pore passing through it
OR
pump protein shown as a transmembrane globular structure
f. cholesterol shown in between adjacent phospholipids