7.1 - Haemoglobin

• What are the haemoglobins ?

  A group of chemically similar molecules found in many different organisms
• What is haemoglobin ?

  A protein with a quaternary structure
• Name of the process in which haemoglobin binds with oxygen and where it takes place in humans ?

  Associating, lungs
• Name of the process in which haemoglobin releases oxygen and where this occurs in humans ?

  Dissociating, respiring tissues
• Describe the structure of haemoglobin ?

  4 secondary polypeptide chains (2 alpha 2 beta), all contain a haem group with Fe2+ ions (binding site)
• Describe how O2 binds to RBCs at the lungs ?

  Associates, haemoglobin has high O2 affinity so readily binds to O2
• Describe how O2 is lost from RBCs at respiring tissues ?

  O2 dissociates, haemoglobin has low affinity for O2 so readily releases O2
• Name of haemoglobin when associated with O2?

  Oxyhaemoglobin
• Name of haemoglobin when dissociated with O2 ?

  Deoxyhaemoglobin