Biology 9700/11 May June 2011 | Cambridge AS Level Past Papers With Mark Scheme

1. Light vs. electron microscopy: comparison of resolution and magnification capabilities for observing cellular structures.

2. Identification of structures in plant cells under a light microscope, including chloroplasts, nucleoli, and cell membranes.

3. Enzyme activity analysis: effects of pH and inhibitors on reaction rates, using catalase and hydrogen peroxide as a model.

4. Properties and structural roles of biological macromolecules: triglycerides, glycogen, collagen, and cellulose.

5. Osmosis in plant cells exposed to sucrose solutions, determining turgidity changes and water potential gradients.

6. DNA replication mechanisms disrupted by drugs inhibiting polymerase or unwinding enzymes, correlating with specific genetic diseases.

7. Water transport in plants: stages involving cohesion, adhesion, osmosis, and transpiration.

8. Gas exchange system adaptations: structural differences in trachea, bronchi, and alveoli for efficient oxygen diffusion.

9. Impact of antibiotics on bacterial resistance: testing zones of inhibition and their correlation with bacterial survival over time.

10. Nitrogen cycle stages: processes like ammonification and denitrification affecting plant nitrogen availability, and ecological implications for nutrient cycling.