Gas Exchange

• diffusion 


  movement of molecules from high concentration gradient to low concentration gradient
• oxygen affinity 


  ability of the haemoglobin to make adaptational changes to bind to more oxygen
• cooperative binding 


  when one oxygen molecule binds to one haem group and alerts the rest of the groups to bind to the oxygen available , due to properties of proteins
• Tense state 


  a state of haemoglobin wherein no oxyge is bound and has low affinity for oxygen
• Relaxed state 


  state of haemoglobin when the oxygen first binds and has a higher affinity for oxygen
• ODC


  Oxygen

  Dissasosciation

  Curve
• partial pressure 


  oxygens pressure to the entire system is positively proportional with the hb saturation %
• maternal haemoglobin 


  2x beta chains

  2x alpha chains
• Fetal haemoglobin 


  2x gamma chains (oxygen from mothers blood)

  2x alpha chains
• two mechanisms that decrease affinity

  • conversion of CO2 and H2O into H+ and HCO3 ions, thus it decreases pH to turn the blood acidic
  • conversion of amine group into carbamate producing -> carbaminohaemaglobin