Explain4 marksStandard
The table below shows the percentage saturation of haemoglobin with oxygen at different partial pressures of oxygen (pO₂) and at two different pH values, representing conditions in the lungs (pH 7.4) and in respiring tissues (pH 7.2).
| pO₂ / kPa | % saturation at pH 7.4 | % saturation at pH 7.2 |
|---|---|---|
| 12 | 98 | 95 |
| 4 | 50 | 40 |
Explain the significance of the differences in haemoglobin saturation at the lungs (pO₂ = 12 kPa) and at respiring tissues (pO₂ = 4 kPa), with reference to the shape of the oxygen dissociation curve and the Bohr effect.