CAIE A Level Biology 9700 · The mitotic cell cycle
The epithelial lining of the small intestine is renewed every few days. This renewal depends on stem cells at the base of the intestinal crypts undergoing repeated mitotic divisions. Describe the structure of a chromosome in these stem cells and the role of telomeres in allowing repeated DNA replication without loss of genetic information.
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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