Biology 9700/21 Oct Nov 2018 | Cambridge AS Level Past Papers With Mark Scheme

1. Structure and diseases of the human gas exchange system, identification of lung anatomy, non-infectious diseases like asthma, malaria pathogen and vaccine challenges, and environmental factors influencing malaria distribution.

2. Lactose digestion by lactase enzyme, water absorption effects due to undigested lactose, immobilization of lactase for industrial use, and comparison of enzyme activity between immobilized and free states at varying temperatures.

3. Plant cell features, cellulose structure in cell walls, role of ATP in metabolic processes, hydrogen bonding in water molecules, and the solvent properties of water for ions.

4. Epithelial cell magnification calculations, cell signaling mechanisms involving VEGF in kidney cells, monoclonal antibody production via hybridoma technology, and repeated treatment challenges with VEGF-targeting antibodies.

5. Prokaryotic cell features distinguishing them from eukaryotes, phloem tissue infection by plant pathogens like Liberibacter, and nucleotide comparisons among DNA, RNA, and ATP.

6. Hemoglobin's oxygen transport efficiency and solubility in water, adaptation of llama hemoglobin to high altitudes, oxygen dissociation curve differences, and advantages of higher oxygen affinity.