608 EXPERIMENT STATION RECORD. 



hypothesis, formic akh^hyde, OH2O, cue of the most easily acted upon 

 of all compounds, is formed from the carbonic acid OH2O3, a molecule 

 of oxygen being liberated. 



Von Uaeyer is of tlie opinion that the formic aldehyde simply polem- 

 erizes to such com])ounds as sugar, etc. I am inclined to believe that 

 the formic aldehyde first becomes a part of the protoplasm molecule, 

 and uniting with the nucleii which are already present in the parent 

 molecule, forms new protoplasm molecules. When, in addition, the 

 reduction products of nitric acid, i. e., ammonia, etc., enter into the mole- 

 cule, it can grow, according to our ideas, almost without limit. If now 

 by catalytic action the unstable molecule is broken up, its disunion can 

 yield albumen, starch, and fat, while a nucleus remains behind to which 

 the formic aldehyde and ammonia and like molecules can unite them- 

 selves again and build new protoplasm molecules. 



The metabolism of protoplasm is constantly discussed, but no attempt 

 is made to explain the causes which i^roduce this metabolism. It seems 

 to me that the foregoing is the most natural explanation. It is indeed 

 a thousand times more probable that the metabolism of matter in 

 animal cells depends upon just such causes, with this difference, ot 

 course, that it is not formic aldehyde but organic substances which are 

 carried to the plasma of the blood and absorbed by the plasma mole- 

 cules. Here also large plasma molecules are built up of perhaps vary- 

 ing constitution. These molecules, under the influence of catalytic 

 action which must perhaps be of a different kind for each sort of cell, 

 break up and split off albumen, fat, sugar, and other compounds, leav- 

 ing behind a nucleus which has the i)ower of taking to itself the proper 

 organic material and growing again to a plasma molecule. 



Simultaneously with the catalytic reactions, processes of an opposite 

 character must take place in the living cell. The catalytic action leads 

 always to a breaking up of complex molecules into simpler ones, and 

 is accompanied by a loss of energy. Thus we see a building uj) also in 

 the vegetable organism ; ceHulose is formed from sugar, and albumen 

 from asparagiu and glutamin, and in the animal organism albumen is 

 formed from peptones. In a word, we have to do with syntheses, and 

 such syntheses not only lead to the formation of these compounds, but 

 have a much more important meaning. They alone render possible the 

 formation of protoplasm molecules. There is, further, this difference 

 between catalytic and synthetic reactions: the first always liberates 

 energy, the second always consumes energy. 



Energy must be supplied to the compounds which take part in syn- 

 thetical reactions. Tliis is done in the chlorophyll cell by the action of 

 light; in all other cells by the breaking down of other organic com- 

 pounds or at the expense of energy- liberated by catalytic reactions. 

 Is there an equilibrium of force in the economy of nature so that the 

 catalytic reactions produce as much energy as is required by the 

 synthetical ! 



