8 



LIVING AND LIFELESS MATTER 



In the ash he found sodium, potassium, iron, magnesium, 

 calcium, phosphoric acid and chlorine. Since then a great 

 variety of different substances have been obtained from cells 

 and tissues of different living things some of which are given 

 in the following partial classification of the proteins. 



CLASSIFICATION OF THE PROTEINS 



C. Derived 

 Proteins 



f Primary 



derivatives 



| Secondary 

 derivatives 



( Proteans 

 J Metaproteins 

 I Coagulated 

 I proteins 

 ( Proteoses 

 \ Peptones 

 I Peptides 



The above list does not give anything like a complete enu- 

 meration of the chemical compounds which make up proto- 

 plasm. Most of the above are merely compounds of C, H, 

 N, O, and P, and vary in the relative percentages of the different 

 elements in combination. In the list only the derivatives of 

 the purine bases are given, but each of the others includes 

 a similar list of substances. Add to these many compounds 

 the various combinations of carbohydrates and fats, and of the 

 minerals Ca, Na, Fe, Mg, etc., and some faint conception may 

 be gained of the enormous number of chemical bodies to be 

 found in protoplasm. 



