Biology 9700/22 May June 2020 | Cambridge AS Level Past Papers With Mark Scheme

1. Characteristics, visualization limits, and mechanisms of host cell entry for picornaviruses, with reference to microscopy and structural analysis.

2. Coordination of mammalian cardiac activity involving SAN and AVN, valve dynamics in response to blood pressure changes, and comparative structural insights of cardiac tissues.

3. Tuberculosis transmission, vaccination coverage disparities, and protective roles of BCG against related bacterial diseases, with trends in global incidence rates.

4. Chondrocyte adaptations, cartilage distribution and functionality in the gas exchange system, and molecular structural analysis of collagen and its functional suitability.

5. Sucrose transport mechanisms in plants via phloem, enzyme-mediated synthesis pathways, and comparative analysis of carbohydrate structures like floridean starch, amylopectin, and glycogen.

6. Phases and checkpoints of the mitotic cell cycle, apoptosis mechanisms, drug impacts on cell cycle progression, and cytological differences in leukemia-affected lymphocytes compared to healthy samples.