Oxygen Dissociation Curve Flashcards
Why is Haemoglobin called a conjugated protein?
It is a spherical protein with a prosthetic group (haem)
What do you call a haemoglobin molecule that is fully saturated?
Oxyhaemoglobin
What is the chemical formula for oxyhaemoglobin?
Hb(O2)4
What is the term for when the shape of a haemoglobin molecule is changed due to the association of the first oxygen molecule?
Positive Cooperation
What does positive cooperation mean?
The association of the first oxygen molecule increases Haemoglobin’s affinity for oxygen
What is the affinity for oxygen at the lungs?
High
Oxygen is released less readily
Associates with oxygen more readily
What is the main difference between fetal and adult Hb?
Fetal Hb has a higher affinity for oxygen
At the lungs what is haemoglobin doing and why?
There is a high partial pressure of oxygen, so this means Hb has a high affinity for oxygen and this means Hb associates to oxygen readily
At respiring tissues what is haemoglobin doing and why?
There is a low partial pressure of oxygen, so this means Hb has a low affinity for oxygen and this means oxygen dissociates from Hb
If a curve is to the left on an oxygen dissociation curve what does this imply about the saturation of Hb?
Hb has a higher saturation at lower Partial pressures of oxygen due to having a higher affinity for oxygen
What happens at low Partial pressures?
Association occurs less rapidly
Dissociation occurs more readily
If an animal has Hb that has a high affinity for oxygen at low partial pressures, what does this mean about them?
They aren’t very active and have a low metabolic rate because dissociation happens less rapidly
What do oxygen dissociation curves show?
The rate at which oxygen associated and dissociates with Hb at different partial pressures of oxygen
What does partial pressure mean?
Pressure exerted by oxygen within a mixture of gases
What does high affinity for oxygen mean?
Associates easily
Dissociates slowly
