CAIE A Level Biology 9700 · Cell membranes and transport
The cell surface membrane is described by the fluid mosaic model. Outline the key features of this model, referring to the roles of phospholipids, cholesterol, and proteins (including glycoproteins) in membrane structure and function. In your answer, explain how hydrophobic interactions between phospholipids contribute to bilayer formation.
5 marks, so the mark scheme is looking for about 5 separate creditworthy points. Making the same point twice in different words earns it once.
Outline means: Give the main points briefly. Less detail than describe, but every key step has to be there. One short line per step, in order. The marks are for coverage, not depth.
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