v Hb - made up of 4 sub units
Cooperative binding:-
v Hb has a greater ability to bind O 2 after a sub-unit has already bound O 2
Hb is more attracted to O 2 when three of the polypepetide chains are bound to O 2.
v O 2 - Hb curve is the relationship between percentage saturation of haemoglobin and partial pressure of
oxygen.
v The O 2 - Hb dissociation curve has a sigmoid shape due to cooperative binding of O 2 to the 4 sub-units of
Hb.
v A right shift indicates decreased O 2 affinity of Hb. This allows more O 2 to be available to the tissues.
OXYGEN - HAEMOGLOBIN DISSOCIATION CURVEBy: KEZIA THEIOPHILLUS
(Green Park International School, Namakkal, Tamil Nadu)