Haemoglobin and oxygen transport
What is haemoglobin?
the protein molecule found in red blood cells that is responsible for carrying most of the oxygen within the bloodstream.
How many subunits make up haemoglobin, and what does each subunit contain?
4 subunits, each of which contain a heme group (binding site)
Describe the cooperative binding of oxygen to haemoglobin.
When one oxygen molecule binds to one of the heme group, the haemoglobin molecule changes shape, increasing the affinity for the binding of other oxygen molecules.
Which would have the greatest affinity for oxygen? Haemoglobin molecules carrying 3 oxygen molecules or carrying no oxygen molecules.
Carrying 3 molecules has a greater affinity for oxygen. When an oxygen molecule binds to a heme group, it changes the haemolglobin's shape in a way that increases its affinity for another oxygen molecule.
Haemoglobin can carry a maximum of how many oxygen molecules?
4
Once all heme groups have an oxygen molecule attatched, it is said to be ______.
Saturated
What site does carbon dioxide bind to hameoglobin at?
Allosteric site
What does the binding of carbon dioxide to haemoglobin result in?
A release of oxygen
Which has a higher affinity for oxygen, the foetal haemoglobin or the mother's haemoglobin?
Foetal
True or false: In the placenta, carbon dioxide concentrations are low compared to oxygen.
False, oxygen molecule concentration is low. Therefore, haemoglobin releases oxygen.
Fetal haemoglobin has a _____ affinity for oxygen compared to adult haemoglobin and therefore the _____ molecules pass through the _______ and is transported to the fetus.
Higher, oxygen, villi walls