CHEMICAL PHENOMENA IN LIFE 



processes on the temperature obeys a similar 

 rule to that of enzyme reactions. Whenever we 

 find an Optimum of a certain vital function at a 

 certain temperature we must think of the crossing 

 of two kinds of influences. One of these in- 

 fluences is the accelerating effect of the tem- 

 perature on chemical reactions, the other the 

 destructive effect of higher temperature on the 

 active substances of living cells. We only have 

 to add that most of these active substances belong 

 to the enzymes. 



It is important that the equilibrium of Enzyme 

 reactions is not altered by temperature. Van 't 

 Hoff has explained this fact. Enzyme reactions 

 cause neither a great production nor a great con- 

 sumption of heat. All reactions of such character, 

 of a comparatively small caloric change are not 

 affected in their equilibrium by temperature. 

 Therefore the constant of equilibrium in enzyme 

 reactions is not dependent on temperature. 



Bright sunlight is very harmful for enzymes, 

 and rays of light destroy them very quickly. 

 Especially the ultraviolet rays act particularly in- 

 juriously on all enzymes hitherto examined. 



Very interesting relations exist between the con- 

 centration of the enzyme solution and the enzyme 

 effect. We have related that many catalytic 

 reactions follow the law of monomolecular reac- 

 tions. So, for example, the destruction of hydrogen 

 peroxide by platinum sol, or the splitting up of cane 

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