8 DYNAMICS OF LIVING MATTER 



chemical reactions: this he called catalytic force. As an example 

 he used Kirchhoff's discovery of the action of dilute acids in the hy- 

 drolysis of starch to dextrose. In this process the acid is not consumed, 

 hence BerzeUus concluded that it did not act through its affinity, but 

 merely by its presence or its contact. Another instance quoted by 

 Berzelius was the decomposition of H2O2 which had been investigated 

 by Thdnard. In acid solution this body is stable ; in alkaline solution, 

 or in the presence of platinum, silver, or gold, or in the presence of 

 fibrin of the blood, it is rapidly decomposed. In this decomposition 

 apparently neither the fibrin, the gold, nor the platinum acted through 

 the force of affinity, but catalytically. He then suggests that the spe- 

 cific and somewhat mysterious reactions in living organisms might be 

 due to such catalytic bodies as act only by their presence, without being 

 consumed in the process. He quotes as an example the action of 

 diastase in the potato. "In aninials and plants there occur thousands 

 of catalytic processes between the tissues and the liquids." The idea 

 of Berzelius has proved fruitful, and the catalytic agencies which in 

 his opinion are responsible for the characteristic reactions in living 

 matter are the enzymes of modern biological chemistry. In some details, 

 however, Berzelius's idea was erroneous. We now know that we have 

 no right to assume that the catalytic bodies do not participate in the 

 chemical reaction because their quantity is found unaltered at the end of 

 the reaction. On the contrary, we shall see that it is probable that they 

 can exercise their influence only by participating in the reaction, and by 

 forming intermediary compounds, which are not stable. The catalyzers 

 may be unaltered at the end of the reaction, and yet participate in it. 



In addition we owe to Wilhelm Ostwald* the conception that the 

 catalyzer does not as a rule initiate a reaction which otherwise would 

 not occur, but only accelerates a reaction which otherwise would indeed 

 occur, but too slowly to give noticeable results in a short time. 



Thus the existence of catalytic agencies, the so-called enzymes in 

 living matter, explains the fact that chemical changes may occur very 

 rapidly in the body at a comparatively low temperature and at a prac- 

 tically neutral reaction. Catalyzers are used extensively in chemical 

 factories, e.g. in the manufacture of sulphuricja^^ that it is impos- 

 sible to see in their presence in Uving matter a specific difference between 

 the chemistry of Hving and inanimate nature. The only difference 

 is, perhaps, that Uving matter manufactures its own catalyzers. This, 

 however, is part of that peculiarity mentioned in the introductory lec- 

 ture, that living machines possess the peculiarity of automatically pre- 

 serving themselves. 



* W. Ostwald, Lchrbuch der allgemeinen Chemie, Vol. II, 2d part, p. 248 1902. 



