Biology 9700/52 Oct Nov 2009 | Cambridge AS Level Past Papers With Mark Scheme

1. Impact of immobilization on Bifidobacterium longum survival in gastric and intestinal conditions using continuous culture systems and fermentation temperature variations.
2. Variables in fermentation systems like pH and nutrient supply control methods for maintaining experimental reliability.
3. Quantification methods for pollen density in air using pollen traps and calculations for volume-specific pollen grain counts.
4. Use of chi-squared tests to evaluate differences in pollen counts under varying environmental conditions, including hypotheses and significance thresholds.
5. Effects of ethanol concentration and temperature on plant cell membrane permeability measured through pigment release.
6. Identification of experimental design flaws, including inconsistencies in replicates and potential anomalies in colorimetry-based absorption data.