Biology 9700/11 Oct Nov 2009 | Cambridge AS Level Past Papers With Mark Scheme

1. Electron microscopy visualization: nucleolus, ribosomes, and chromosomes identified as structures visible only with high resolution.

2. Features of prokaryotic cells: presence of ribosomes, division by binary fission, and lack of organelles like the endoplasmic reticulum.

3. Protein structure stabilization: covalent, ionic, and hydrogen bonds contributing to primary, secondary, and tertiary forms.

4. Translocation mechanism: sucrose active loading into phloem, hydrostatic pressure generation, and mass flow to sink tissues.

5. Starch hydrolysis: enzyme activity analysis using amylase, reaction rates at varying concentrations, and substrate-product dynamics.

6. Leaf section examination: vascular tissue identification, xylem and phloem positions, and adaptations for water and nutrient transport.

7. Immune response roles: B-lymphocyte production of antibodies, memory cell formation, and function during primary and secondary exposures.

8. Arctic ecosystem structure: energy transfer among producers (phytoplankton) and apex predators (polar bears) across trophic levels.