CAIE A Level Biology 9700 · Enzymes
A student investigates the effect of pH on the activity of amylase. They set up a series of buffered solutions at different pH values and add a known concentration of amylase and starch. To measure the rate of reaction, they decide to use a colorimeter. Outline how the student could use a colorimeter to determine the rate of hydrolysis of starch at each pH.
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.
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.
Written by Markquill to follow the Cambridge International syllabus. Markquill is independent and is not affiliated with or endorsed by Cambridge International.