Cell-Theory not Sufficient for Explaining Or(jamsm 191 



and difFcreiitiatioii of" the ur^anisin, and in strict su])ordiiia- 

 tion to its needs. In a word, we are led to see tliat cells 

 must be regarded as organs of the organism just as muscles 

 and glands and hearts and eyes and feet are so regarded. 

 They undoubtedly constitute a class of organs rather sharp- 

 ly set off from all other classes, but this should not be 

 permitted to obscure the equally important fact of their 

 always presenting those attributes which are most general 

 to all organs, namely those of origination by the growth 

 and differentiation of the organism, and of being function- 

 ally subservient to the organism. 



Nor should we, while taking note of the attributes of 

 cells which range them under the general category organ^^ 

 neglect to note also the attributes which make them a class 

 by themselves within that category, namely their similarity 

 in form, constitution and size, for the whole organic world, 

 and of still more importance, their office as the implements 

 or tools by which the organism performs the physical 

 chanxres and chemical transformations of the materials it 

 uses. 



Advance Toward the Organismal Standpoint Through Con- 

 ception of the Cell Reached hy Biochemistry Pursued 

 in Accordance with the Principles of 

 Physical Chemistry 



This last statement turns us back to the concluding sen- 

 tences of the chapter on The Organism and Its Chemistry. 



Our explorations in that field discovered, it will be re- 

 called, that biochemistry, prosecuted in accordance with the 

 principles of physical chemistry, is being led to conceive 

 the cell as a "highly differentiated system," or an "organ- 

 ized laboratory" consisting largely of "colloidal complexes" 

 which constitute, "as it were, a special apparatus for per- 

 forming dynamic chemical events." 



