Gas exchange - the Bohr shift Flashcards
What is the Bohr effect?
Changes in the oxygen dissociation curve as a result of carbon dioxide levels
What happens to haemoglobin’s affinity for oxygen when the partial pressure of carbon dioxide is high?
It is reduced
In which tissues does the Bohr effect primarily occur?
Respiring tissues
What waste product of respiration leads to the Bohr effect?
Carbon dioxide
How does carbon dioxide affect the pH of blood?
It lowers the pH
What does CO2 combine with to form carbonic acid?
Water
What are the products of carbonic acid dissociation?
Hydrogen carbonate ions and hydrogen ions
What role do hydrogen ions play in the Bohr effect?
They bind to haemoglobin, causing the release of oxygen
Why is the Bohr effect beneficial?
It allows haemoglobin to give up its oxygen more readily in respiring tissues
What happens to the dissociation curve on a graph when CO2 levels increase?
The curve shifts to the right
What does a rightward shift in the dissociation curve indicate?
Lower percentage saturation of haemoglobin at any given partial pressure of oxygen
