CAIE A Level Biology 9700 · Cell membranes and transport
A research student analysed the composition of a cell surface membrane and identified four key components: phospholipids, cholesterol, glycoproteins, and channel proteins. Describe the role of each of these components in maintaining the integrity and functionality of the membrane.
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.
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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