Biology 9700/33 May June 2022 | Cambridge AS Level Past Papers With Mark Scheme

- Investigation of enzyme activity in plant cells, specifically the breakdown of hydrogen peroxide.
- Effect of pH on enzyme activity, with buffers at pH 5, 6, 7, 8, and 9.5.
- Measurement of time taken for filter paper discs to rise in hydrogen peroxide solution as an indicator of enzyme activity.
- Hypothesis testing regarding the relationship between pH levels and enzyme activity.
- Control measures for experimental accuracy, including the use of fresh hydrogen peroxide solution.
- Temperature effects on enzyme activity, with preheating at selected temperatures and standardized pH.