Haemoglobin can be found in RBC of all vertebrates and in the TISSUES of some invertebrates.
Its function is to transport oxygen around the body to where it is needed for RESPIRATION (from the lungs to the heart).
It has 4 polypeptide chains; 2 beta and 2 alpha, associated with a haem grp/molecule.
4* structure- 2+ polypeptide chains bonded together by H, ionic or disulfide bonds; sometimes with an additional grp on the side.
Loading/association- HG combines with oxygen (lungs)
Unloading/dissociation- HG releases oxygen (tissues)
HG associates with oxygen when its present in high [ ]. This means that HG takes up oxygen in the lungs when [ ] in air are high, but releases it when it reaches the tissues where [ ] are low.
Affinity- HG ability to associate readily with Oxygen
Factors that affect affinity:
Region of body 02 [ ] <- (at inspiration) -> C02 [ ] Affinity of HG for O2 Result
Gas exchange surface High Low High O2 is loaded
(alveoli) (attaches to HG)
Respiring tissues Low High Low O2 unloaded
(working muscle) (released from HB)
Its function is to transport oxygen around the body to where it is needed for RESPIRATION (from the lungs to the heart).
It has 4 polypeptide chains; 2 beta and 2 alpha, associated with a haem grp/molecule.
4* structure- 2+ polypeptide chains bonded together by H, ionic or disulfide bonds; sometimes with an additional grp on the side.
Loading/association- HG combines with oxygen (lungs)
Unloading/dissociation- HG releases oxygen (tissues)
HG associates with oxygen when its present in high [ ]. This means that HG takes up oxygen in the lungs when [ ] in air are high, but releases it when it reaches the tissues where [ ] are low.
Affinity- HG ability to associate readily with Oxygen
Factors that affect affinity:
- oxygen [ ]
- CO2 [ ]
- pH
- Temperature
Region of body 02 [ ] <- (at inspiration) -> C02 [ ] Affinity of HG for O2 Result
Gas exchange surface High Low High O2 is loaded
(alveoli) (attaches to HG)
Respiring tissues Low High Low O2 unloaded
(working muscle) (released from HB)