CHEMICAL PHENOMENA IN LIFE 



one of the chief tasks in explaining chemical 

 phenomena in life to study the different chemical 

 reactions which take place in living protoplasm. 



Chemists working with lifeless material have 

 as a rule to cause reactions by experiment, since 

 the material does not undergo any change by 

 itself. Comparatively few substances are readily 

 affected by the water and oxygen contained 

 in the surrounding air, without the help of the 

 experimenter. The biologist, on the contrary, 

 may watch numerous chemical reactions which 

 take place in living matter without his aid. It 

 is, however, difficult to study chemical reactions 

 in life in that way, because the single results cannot 

 be distinguished or separated from each other. 

 Results by far more exact are obtained when in an 

 experiment we bring together the living organism 

 with a certain substance to see what reactions are 

 caused. So we may watch the favourable or 

 unfavourable influence of this substance on the 

 living cells as well as the chemical transformation of 

 this substance by the living organism, when we 

 later on subject the organism to chemical analysis 

 or when we examine the products excreted by the 

 living cells. A great number of most valuable 

 results were obtained by such methods. Especially 

 the gradual change of substances taken up into 

 living cells by different reactions may be well 

 studied in that way. 



The next step is to learn what kind of chemical 

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