Biology 9700/12 Oct Nov 2011 | Cambridge AS Level Past Papers With Mark Scheme

1. Biological molecules: identification of disaccharides, structure of proteins resistant to urea, and polysaccharide polymer types including amylopectin and glycogen.

2. Enzyme mechanisms: effects of competitive and non-competitive inhibitors, substrate concentration, and estimation of lactate dehydrogenase activity.

3. Membrane transport processes: facilitated diffusion, osmosis, and active transport, analyzed in red blood cells and plants adapted to cold climates.

4. Cell division distinctions: chromosome numbers post-mitosis vs. meiosis, genetic engineering processes, and spindle fiber dynamics during mitosis.

5. Cardiac cycle analysis: blood pressure changes in left ventricle, oxygen transport in red blood cells, and carbon dioxide's role in bicarbonate buffer system.

6. Ecosystem energy flow: nitrogen cycle processes, root pressure in plant water movement, and limited trophic energy transfer sustaining fewer top consumers.

7. Immune response: active vs. passive immunity, antigen-antibody interactions, and pathogens causing diseases like cholera and malaria.