FUNCTIONS OF THE NUTRIENTS 



153 



conductivity or are inert, and it is the presence of the 

 mineral elements in solution carrying electrical charges 

 which makes possible the reactions involved in metabolism. 

 Without the mineral elements protoplasm would be dead. 

 219. Relation of mineral elements to animal struc- 

 ture. The mineral elements are largely involved in the 

 structure of the animal body. They constitute the entire 

 amount of the ash in which the elements calcium and 

 phosphorus exist in the largest proportions. The follow- 

 ing table illustrates the kinds and distribution of mineral 

 elements in the bodies of five species of farm animals. 



TABLE XXVII 



