Biology 9700/12 May June 2015 | Cambridge AS Level Past Papers With Mark Scheme

1. Functional and structural characteristics of cell organelles, ribosomes, and plasmodesmata in plants and bacteria.
2. Properties and bond types in biomolecules like proteins (α-helix, β-sheet) and carbohydrates (cellulose, glycogen).
3. Mechanisms of enzyme activity, including lock-and-key hypothesis, competitive and non-competitive inhibition.
4. Membrane permeability factors, active and facilitated diffusion, and cell fluidity determinants.
5. Role of hemoglobin in oxygen transport, Bohr effect, and factors influencing oxygen dissociation curves.
6. Tobacco-related respiratory conditions, mechanisms of elastic fiber damage, and differences in lung diseases such as emphysema and chronic bronchitis.
7. Energy transfer efficiency in ecosystems, roles of decomposers, and nutrient cycling in agricultural systems with leguminous crops.