Biology 9700/23 Oct Nov 2010 | Cambridge AS Level Past Papers With Mark Scheme

1. Structural composition and functions of cell membrane molecules, including the phospholipid bilayer and membrane proteins.

2. Tuberculosis (TB) global incidence patterns, mode of transmission of Mycobacterium tuberculosis, and challenges of eradicating multi-drug resistant TB.

3. Sucrase enzyme mechanism in sucrose hydrolysis, role of sucrase in phloem unloading, and reasons for starch conversion for storage in plant sinks.

4. Immune response roles of T-lymphocytes and B-lymphocytes, antibody concentration dynamics post-antigen exposure, and predictions for secondary immune response.

5. Alveoli structure adapted for efficient gas exchange; impact of emphysema on alveolar surface area, gas exchange efficiency, and related symptoms.

6. Soil food web nutrient flow, magnesium's biological role, trophic level dynamics, and ecosystem contributions of soil organisms.