Biology 9700/52 May June 2023 | Cambridge AS Level Past Papers With Mark Scheme

1. Enzyme activity investigation, focusing on polyphenol oxidase in bananas and its dependence on pH, monitored through colorimetry using dopamine hydrochloride as the substrate.

2. Standardized procedures for colorimetric analysis, emphasizing control of temperature, substrate concentration, and use of colorimeter filters at 470 nm.

3. Application of Spearman's rank correlation to study the relationship between distance from a road and lichen abundance as a bioindicator of air pollution.

4. Evaluation of anti-browning agents, comparing their inhibitory effects on polyphenol oxidase from different plant sources and their mechanisms of inhibition.

5. Methods for calculating enzyme reaction rates, initial rate analysis, and the impact of non-competitive inhibitors like sulfur-containing molecules on enzyme kinetics.

6. Detailed experimental design for investigating substrate concentration effects on enzymatic activity, including step-by-step dilution and reaction monitoring protocols.