Four students describe why breathing rate and heart rate increase during exercise. Which explanation contains the necessary linked reasoning?
More glucose enters the lungs, so the lungs pump oxygenated blood to muscle cells
More oxygen reaches muscle cells, so aerobic respiration can transfer energy faster
More lactic acid reaches muscle cells, so anaerobic respiration can stop immediately
More carbon dioxide reaches muscle cells, so glucose can be completely oxidised
51 exam-style questions on AQA GCSE Biology 4.2 Respiration, covering 4.2.1 Aerobic and anaerobic respiration, 4.2.2 Response to exercise, and 4.2.3 Metabolism. Each one has a worked solution and a mark scheme showing where the marks go.