THE CHEMISTRY OF PHOTOSYNTHESIS 



119 



CO 03 



.2S 



' 0) 



o ^ 



— CO 



3 O 



■C Q. 



0) 



"cO 



-C 



Q. 



CO 



O 

 CO 



I 



0) 

 CO 

 O 



o 



05 



CM 



o 

 o 



o 



c 

 o 

 o 



_3 



O)' 



o 



JI 

 Q. 

 CO 



O 



JZ 

 D. 



CD 



o 

 o 



CD 



i CO 



o Q- 

 ■*-•(/}- 



O o 



4r Q. 

 CD 



0) 



0) CO 

 CO x: 

 O Q. 

 CO - 



o 



o 



3 



Aci) 



0} 



■»-• 

 CO 

 JC 

 Q. 

 CO 

 O 

 .C 

 Q. 



00 



I 



CO 



o 



O 



O 



O) o. 



c 

 o 

 o 



CO 



o 



JZ 



Q. 

 CD 



CO 



Fig. 45. The pentose phosphate pathway (Racker). 



main together in a molecule triose phosphate. In Figure 46 I represents the 

 oxidative decarboxylation of glucose-6-phosphate to xylulose-5-phosphate as 

 well as the condensation of the latter with ribose-5-phosphate. This is the 

 transketolase reaction producing sedoheptulose-7-phosphate and triose phos- 

 phate. In II we have the transaldolase reaction in which erythrose-4-phos- 

 phate and fructose-6-phosphate are produced. The latter gives off COo by 

 oxidative decarboxylation, leaving pentose phosphate. Finally, III shows 



