Biology 9700/22 May June 2019 | Cambridge AS Level Past Papers With Mark Scheme

1. Structural and functional distinctions between roots and stems in Helianthus annuus, with detailed comparison of xylem vessel elements and phloem sieve tube elements.

2. Mucus production mechanisms in the gas exchange system, glycosylation processes, chloride ion roles in mucus formation, and mitosis in respiratory system maintenance.

3. Identification and roles of human blood cells, mechanisms behind elevated white blood cell counts in diseases like CLL and measles, and adaptive responses to high altitude through increased red blood cell production.

4. Structural features of Vibrio cholerae, calculations of cholera case fatality rates, and analyses of trends and outbreaks in response to environmental disruptions like earthquakes.

5. Classification of biological molecules into monomers and polymers, and structural properties of phospholipids facilitating bilayer formation in cell membranes.

6. Catalase activity investigations, including effects of surface area on reaction rates and temperature on enzyme activity, illustrated through experimental setups and reaction kinetics.