Appendix II. Aggregation of haemoglobin 315 



A better conception of the effect of C0 2 will be derived from the following figure : 

 3 



2-5 



FIG. 156. Relation of ;i (ordmate) to CO 2 pressure (abscissa) in dissociation curve 



of dialysed haemoglobin. 



It is clear that the reason why the value of n is almost unaffected by C0 2 in blood 

 is because 2'5 is nearly the maximal value. This has been effected by the salts 

 present. 



It is clear also that extreme concentrations of C0 2 may raise the value of n 

 to a slight extent as it appears experimentally to do in the body. The effect of the 

 salts then is to render the system stable and prevent large changes in the clumping 

 of the molecules which would otherwise occur as the result of changes in reaction. 

 The relative stability of the two systems may be judged from the following data : 



Haemoglobin 



Blood 



71 



A' 



no C0 2 



I 

 111 



40 mm. C0 2 



2-5 

 00043 



no C0 2 



2-5 

 00258 



40 mm. C0 2 



2-5 

 00029 



