CAIE A Level Biology 9700 · Energy and respiration
Describe how you would use a simple respirometer to determine the respiratory quotient (RQ) of germinating sunflower seeds, which respire primarily by oxidising stored lipids. Include in your answer the balanced equation for the complete aerobic respiration of the fatty acid palmitic acid (C16H32O2), and explain how the RQ value would be calculated from your experimental measurements.
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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