THE NATURE OF PHOTOSYNTHESIS 



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suits in the fermentation reaction attaining a maximal rate at a certain 

 temperature but with a continuation of this temperature decreasing and 

 finally falling to zero when all the ferment has been destroyed. 



Duclaux has pictured the phenomenon as shown in Figure 14. In 

 this the curve OA represents the rate of reaction with increasing tem- 



Fig. 14. — Influence of temperature and time on the rate of photosynthesis. 



(Blackman.) 



perature, DB is the rate of destruction of the ferment with temperature 

 and OAIC the observed rate of the fermentation reaction with increas- 

 ing temperature. This general view has been applied to the observed 

 maximal rates of photosynthesis at different temperatures. Thus OA 

 would represent the rate of photosynthesis with increasing temperature, 

 DB would be the inactivation of the chloroplasts due to higher tempera- 



