Biology 9700/01 May June 2007 | Cambridge AS Level Past Papers With Mark Scheme

1. Prokaryotic vs. eukaryotic cell comparison: structural differences including ribosomes, DNA forms, and organelle absence in prokaryotes.

2. Biological molecule tests: reducing sugar detection in polymers via hydrolysis followed by Benedict’s test.

3. Cellulose and glycogen structure-function relationships: branching in glycogen for energy storage, linear hydrogen bonds in cellulose for support.

4. Enzyme functionality: urea's effect on protein structure, breaking non-covalent bonds while retaining primary structure.

5. Plant water transport: osmosis and water potential gradients between xylem, root cells, and soil.

6. Oxygen transport in mammals: hemoglobin interactions, carbon dioxide combinations forming carbaminohemoglobin.

7. Antibiotic resistance mechanisms: differential bacterial responses to streptomycin and penicillin, impact of overuse.

8. Energy flow limits in ecosystems: inefficiency in energy transfer restricting trophic levels and biomass accumulation.

9. Nitrogen cycle roles: processes including nitrification, denitrification, and nitrogen fixation across soil and atmosphere.

10. Immune response dynamics: plasma cell antibody production, memory cell formation, and active vs. passive immunity.