Haemoglobin

• Red blood cells contain haemoglobin
• Haemoglobin is a large protein with a quaternary structure.
• Each Haemoglobin chain has a haem group which contains iron and gives haemoglobin its red colour
• Haemoglobin has a high affinity for oxygen - each molecule can carry four oxygen molecules
• In the lungs, oxygen joins to the iron in haemoglobin to form oxyhaemoglobin.
• Oxyhaemoglobin is a reversible reaction - where oxygen leaves oxyhaemoglobin near the body cells, it turns back into haemoglobin.