Biology 9700/01 May June 2004 | Cambridge AS Level Past Papers With Mark Scheme

1. Microscopy and cell size: electron microscope resolution due to short wavelengths; size hierarchy among nuclei, mitochondria, ribosomes, and starch grains.

2. Biomolecules: peptide and glycosidic bond identification, haemoglobin’s quaternary structure with four haem groups, and triglycerides as high-energy storage molecules.

3. Enzymatic activity: non-competitive inhibitors, enzyme specificity in drug design for AIDS protease inhibition, and conditions affecting enzymatic hydrolysis.

4. Membrane transport: mechanisms like endocytosis and active transport, role of membrane components like cholesterol in fluidity, and osmotic effects on plant cells.

5. Circulatory system dynamics: systolic blood pressure definitions, valve functionality during the cardiac cycle, and Purkyne tissue's role in electrical excitation.

6. Respiratory system: gas exchange membrane count for oxygen diffusion, alveolar and bronchial cell types, and nicotine's role in cardiac risk via vasoconstriction.

7. Immunology: primary immune responses driven by phagocytes, antigen-specific blood transfusion compatibility, and antibody formation.

8. Ecosystem and nitrogen cycle: decomposer roles in ammonium conversion, energy transfer inefficiencies limiting top consumer numbers, and trophic level energy dynamics.