Practise reading oxygen dissociation curves, linking haemoglobin structure to oxygen affinity, and comparing adult, fetal and myoglobin responses with marked evidence.
Sickle cell disease is caused by a gene mutation affecting the -globin chain of haemoglobin.
The red blood cells in a person with sickle cell disease are sickle shaped and less elastic. They also have a shorter lifespan than healthy red blood cells.
These sickle shaped red blood cells cannot carry as much oxygen as healthy red blood cells and they get stuck in the capillaries.
The graph shows oxygen dissociation curves for groups of people with sickle cell disease and those without the disease.
The shaded areas represent the range of values for each group of people.
Percentage of haemoglobin saturated with oxygen (\%)
Identify two conclusions, other than the difference in p50 values, that can be made from this graph.
Conclusion 1
Conclusion 2
Sickle cell disease can result in death.
Explain why the changes in the structure of haemoglobin and the shape of the red blood cells could result in death in a person with sickle cell disease.