CHAPTER VI 



RELATION BETWEEN MINERALS, PLANTS, AND 

 ANIMALS 



THERE are no independent members of creation : all 

 things touch upon one another. The matter of the liv- 

 ing world is identical with that of the inorganic. The 

 plant, feeding on the minerals, carbon dioxide, water, 

 and ammonia, builds them up into complex organic com- 

 pounds, as starch, sugar, gum, cellulose, albumen, and 

 gluten. When the plant is eaten by the animal, these 

 substances are used for building up tissues, supplying 

 energy, repairing waste, laid up in reserve as glycogen 

 and fat, or oxidized in the tissues to produce heat. The 

 albuminoids are essential for the formation of tissues, 

 like muscle, nerve, cartilage ; the ternary compounds 

 help in repairing waste, while both produce heat. When 

 oxidized, whether for work or warmth, these complex 

 compounds break up into the simple compounds, 

 water, carbon dioxide, and (ultimately) ammonia, and as 

 such are returned to earth and air from the animal. 

 Both plant and animal end their life by going back 

 to the mineral world : and thus the circle is complete 

 from dust to dust. Plants compress the forces of 

 inorganic nature into chemical compounds ; animals 

 liberate them. Plants produce; animals consume. The 

 work of plants is synthesis, a building-up ; the work 

 of animals is analysis, or destruction. Without plants, 

 animals would perish ; without animals, plants had no 

 need to be. 



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