CAIE A Level Biology 9700 · Cell membranes and transport
A student is studying the structure of a cell surface membrane using the fluid mosaic model. The table below lists four components of this membrane.
| Component |
|---|
| Phospholipids |
| Cholesterol |
| Glycoproteins |
| Channel proteins |
Describe the role of each of these components in the cell surface membrane.
4 marks, so the mark scheme is looking for about 4 separate creditworthy points. Making the same point twice in different words earns it once.
Describe means: Say what happens or what something is like, in order and with detail. You are not being asked why. If there is data, quote it: name the trend, then give figures with units at the points where it changes.
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