Biology 9700/42 Oct Nov 2012 | Cambridge AS Level Past Papers With Mark Scheme

E1. Sequence of events in synaptic transmission at cholinergic synapses, roles of calcium ions, acetylcholine, and sodium channels.
2. Mechanisms of antibiotic action (penicillin) on bacterial cell walls and bacterial resistance development via efflux pumps encoded by plasmid genes.
3. Genetic engineering processes for gene insertion in E. coli, use of marker genes like GFP, and limitations of GFP compared to enzyme markers.
4. Spermatogenesis stages, spermatid maturation in mammals, and impact of temperature and genetic mutations on fertility in Caenorhabditis elegans.
5. Advantages of cross-pollination over self-pollination in plants, effects of environmental exposure on maize pollen viability, and implications for GM pollen dispersal.
6. Role of ATP in glycolysis, link reaction specifics, mitochondrial respiration stages, and ATP's function as a universal energy currency.
7. Coral reef ecosystem biodiversity, human-induced damage causes, and comparative risks to coral reefs in Caribbean, Indian, and Pacific Oceans.