Biology 9700/51 Oct Nov 2022 | Cambridge AS Level Past Papers With Mark Scheme

- Antibiotic resistance in bacteria, global health issue, research into antibacterial substances, honey as an alternative.
- Manuka honey, antibacterial properties, methylglyoxal (MGO), hydrogen peroxide, Bacillus subtilis, aerobic respiration.
- Measurement of bacterial growth, turbidity as an indicator, broth culture methodology, control experiments.
- Preparation of dilutions, concentration calculations, stock solutions, 10% honey solution, graduated pipettes.
- Independent and dependent variables, experimental design, prediction of results, statistical analysis using chi-squared test.
- Gossypol toxicity in livestock, dietary impacts on milk production, genetically modified cotton plants, risk assessment of gossypol intake.