Haemoglobin oxygen-binding curve

Fig. 6.2. Haemoglobin-oxygen binding curve. Note the increase in sigmoidicity as the Hill coeflicient (h) increases from I to 5.

Figure 13.5 (a) The structure of sperm whale myoglobin. (From Voet and Voet, 2004. Reproduced with permission from John Wiley Sons., Inc.) (b) The oxygen-binding curves of myoglobin and haemoglobin. (Reprinted with permission from Collman et al., 2004. Copyright (2004) American Chemical Society.)... 

The oxygen-binding curves for myoglobin(Mb) and haemoglobin(Hb), showing also the pH-dependence(Bohr effect). 

Thus, for haemoglobin (Hb) the oxygen binding curves are sigmoidal as is shown in the above figure. The fact that n exceeds the unit can be ascribed physically to the fact that attachment of 02 to one haem group increases the binding constant for the next 02, which in turn increases the constant for the next one and so... 

Fig. 1 Dissociation curves—the relationship between PO, and oxygen binding to haemoglobin (a) The normal oxygen-haemoglobin dissociation curve, (b) The effect of MWr CO.

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