AQA A LEVEL BIOLOGY Paper 2 MS 2021

AQA A LEVEL BIOLOGY Paper 2 MS 2021. MARK SCHEME − A-LEVEL BIOLOGY − 7402/2 − JUNE 2021 Question Marking Guidance Mark Comments 1. Phosphorylation based on glucose using ATP; 2. Oxidation based on triose phosphate to pyruvate; Accept all mark points within diagrams. 3. Net gain based on ATP; 4. NAD reduced; 2. Accept removal based on hydrogen from triosephosphate for oxidation. 01.1 4 max 3. Accept any description that indicates a net gain e.g., 4 produced, 2 used. 4. Accept NADH/NADH2/NAD H + H + produced. Question Marking Guidance Mark Comments 01.2 1. Less/no reduced NAD/coenzymes OR Fewer/no hydrogens/electrons removed (and passed to electron transfer chain); 2. Oxygen is the final/terminal (electron) acceptor; 2 1. Accept less/no FAD reduced.