Haemoglobin

• What does haemoglobin do?

  Transports oxygen around the body in the red blood cells
• What does the loading of haemoglobin mean?

  The binding of oxygen to haemoglobin
• What does the unloading of haemoglobin mean?

  When oxygen detaches or unbinds from haemoglobin.
• In which pO2 is oxygen loaded and unloaded?

  Oxygen is loaded in regions with a high partial pressure of oxygen (e.g. alveoli) and is unloaded in regions of low partial pressure of oxygen (e.g. respiring tissues).
• Define quaternary protein.

  A protein with more than one polypeptide chain bonded together by ionic, hydrogen and disulphide bonds
• Describe the structure of haemoglobin.

  • 4 polypeptide chains
  • 2 alpha chains
  • 2 beta chains
  • Prosthetic group called the heme group
  • Iron ions which bind to the oxygen
  • Hb can bind to 4 oxygen molecules
• Define the affinity of haemoglobin.

  The ability of haemoglobin to attract / bind to oxygen
• What does it mean when haemoglobin is saturated?

  When haemoglobin is holding the maximum amount of oxygen it can hold