5 6 7 



p02 mm Hg 



Fig. 3. Oxygen dissociation curve of human Mb II (4 x 10 -^M), at 20° C and pH 8; 



+ 0.5- 



-0.5- 



0.00320 



1 



0.00350 



1/T 



Fig. 4. Influence of temperature on oxygen affinity of human Mb I 9 and Mb II o; 



pH 8, borate buffer 1=005 . K=— ^ %-. Mb I JH=-13-5 kcal; Mb II JH=-13-3 



Mb X PO2 



kcal (calculated from the slopes of the lines.) 



