Biology 9700/42 Oct Nov 2009 | Cambridge AS Level Past Papers With Mark Scheme

1. Comparison of features and processes across the five kingdoms, including the presence of 80s ribosomes, chitin, and autotrophic or heterotrophic capabilities.
2. Mechanisms and types of speciation observed in Madeira’s Mus musculus populations, with emphasis on geographical isolation and chromosomal variations.
3. Penicillin's mode of action on bacterial peptidoglycan cross-links and differences in susceptibility between Gram-positive and Gram-negative bacteria.
4. Water-holding capacity effects on crop yields of sorghum and wheat under controlled irrigation conditions, with additional factors influencing plant growth.
5. Spermatogenesis stages, including cell types (haploid and mitotic) and energy requirements fulfilled by mitochondrial abundance in sperm cells.
6. Advantages of gene technology in producing human insulin and addressing ethical or efficiency concerns compared to animal-derived insulin.
7. Inheritance patterns of MN blood group alleles across human populations, with allele frequency variations and implications for genetic diversity.
8. Light intensity effects on photosynthesis rates, with experimental setups using algal discs, limiting factors, and energy transfer efficiency in aquatic environments.