CAPE Biology Unit 2 · 2011 · Paper 1 · Question Q24

Item 24 refers to the graph below which shows the sigmoid (S-shaped) dissociation curve for haemoglobin of a human adult. During cycling, the partial pressure of oxygen found in the pulmonary vein leaving the lungs and in a vein leaving a muscle is MOST likely

1. (A)pO_2 in pulmonary vein: 0 kPa; pO_2 in vein leaving muscle: 12 kPa
2. (B)pO_2 in pulmonary vein: 2 kPa; pO_2 in vein leaving muscle: 12 kPa
3. (C)pO_2 in pulmonary vein: 6 kPa; pO_2 in vein leaving muscle: 6 kPa
4. (D)pO_2 in pulmonary vein: 12 kPa; pO_2 in vein leaving muscle: 2 kPa

This question uses a figure or table from the paper — you'll see it when you practise.