Biology 9700/05 May June 2009 | Cambridge AS Level Past Papers With Mark Scheme

1. Identification of water-conducting tissue in a stem using dye uptake: observation of stained xylem vessels after cutting cross-sections.

2. Water movement rate estimation using dye and potometer setup: calculation based on distance traveled by dye in a specific time.

3. Snail predation study: comparison of banded vs. unbanded shell proportions in areas with and without predatory birds, analysis of selective predation impact.

4. Population estimation in snails using mark-recapture method: reliability differences between 24-hour and 72-hour intervals due to marked sample loss.

5. Effect of initial pH on Rhodotorula glutinis growth rate: mean and standard deviation comparison highlighting optimal conditions for enzyme production.

6. T-test application to evaluate growth rate significance across pH levels, limitations of single variable testing in enzyme optimization conclusions.