Biology 9700/12 March 2019 | Cambridge AS Level Past Papers With Mark Scheme

1. Magnification calculations and representation of cell structures using light microscopy versus electron microscopy.

2. Identification of shared features between chloroplasts and mitochondria, including 70S ribosomes and circular DNA, and the role of organelles in protein synthesis.

3. Distinction between competitive and non-competitive enzyme inhibitors based on active site interactions and effects on enzyme activity.

4. Transport mechanisms of water in plants via cohesion-tension and mass flow within xylem vessel elements.

5. Differences in xylem lignin properties affecting structural support and water transport in tall plants, and analysis of phloem sap transport under heat stress.

6. Oxygen dissociation trends in mammals of varying sizes and the correlation of haemoglobin properties with metabolic activity and oxygen release efficiency.