Biology 9700/02 Oct Nov 2005 | Cambridge AS Level Past Papers With Mark Scheme

1. Goblet cells in gas exchange: mucus secretion role in trapping particles, glycoprotein structure, and locations in the trachea and bronchi.

2. Phospholipid arrangement in membranes: bilayer structure with hydrophilic heads and hydrophobic tails, differences between triglycerides and phospholipids, and triglycerides as energy storage molecules.

3. HIV infection: viral replication in T lymphocytes, modes of transmission, and challenges in controlling its global spread.

4. Mammalian circulation: closed double system benefits, red blood cell adaptations for oxygen transport, and immune responses involving B-lymphocytes and antibodies.

5. Osmosis in yam cubes: surface area-to-volume ratio effects on mass change rate, water potential influence, and comparative percentage mass increases.

6. Haemoglobin structure: globular vs. fibrous protein differences, translation of mRNA codons for β-globin amino acids, and maintenance of tertiary protein structure through bonds and interactions.