106 PROBLEMS IN PHOTOSYNTHESIS 



Figure 43 shows, according to Burk (9), that in Nature the photosynthetic 

 efficiency for the conversion of hght energy into chemical energy attains 1% 

 as an upper hmit. However, in the laboratory it is possible to obtain an 

 efficiency of at least 90% under optimal experimental conditions. Photo- 

 synthesis indeed is a thermodynamic perfection of Nature (see addendum). 



As already stated in § 35, the light reaction of photosynthesis is nothing 

 but the photodissociation of a pigment comparable with the photodissociation 

 of iron carbonyl compounds. It is therefore self-evident that the quantum 

 requirement in the light reaction must necessarily be 1 . The problem of the 

 energetics of photosynthesis can be considered to be definitively solved. 



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