CHEMICAL PHENOMENA IN LIFE 



is exercised on the protein-splitting enzyme 

 of the stomach-secretion by hydrochloric acid or 

 another acid in sufficient concentration. Many of 

 the enzymes of plant cells are favourably influenced 

 in their action by acids quite in the same way. 

 The pancreatic enzyme on the other hand shows 

 a contrary behaviour. It is supported by diluted 

 alkaline solutions. Very remarkable is the 

 activating effect on the fat-splitting enzyme of the 

 pancreatic gland exerted by the organic acids 

 of bile, the glycocholic and taurocholic acid. 



Such activating effects are extremely widely 

 spread in the part which enzymes play in the life- 

 process. One sees how these enzyme effects may 

 be regulated, strengthened, and weakened, as 

 the effects are required. 



Many chemical substances hinder enzyme 

 reactions in a most characteristic manner. Stronger 

 acids or stronger alkalis generally diminish the 

 enzyme effects as also alcohol, formaldehyde, 

 cyanide of potassium, aromatic substances, and 

 many inorganic substances, such as the salts of 

 heavy metals, iodine, sulphurous acid, etc. Such 

 a paralysing influence is not only exercised by 

 these substances, but the living cell is able to 

 produce special substances, which are destroyed 

 by heat, which are effective in very small quanti- 

 ties, and which paralyse enzyme reactions. We 

 have spoken of these already as the Anti-Enzymes. 

 Anti- enzymes are doubtless produced in the 

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