KATABOLISM. ^21 



tenance, but also for growth and activities of all kinds ? 

 These are obviously the questions most fundamental in 

 physiology. 



In answer to the first question we may say that in 

 the passing of matter from a more complex to a simpler 

 condition, from a more unstable to a stabler condition, 

 as in combustion or in organic decomposition, force or 

 energy is liberated which is converted partly into heat 

 and partly also into other forms of energy, mechanical 

 or vital. To illustrate : Matter on a high plane (organic 

 matter) running down (katabolism) to a lower plane 

 (C0 2 and H 2 0) generates force to raise (anabolism) other 

 matter (food) from a lower to a higher plane (tissue). 

 Thus while a large part of the force of plant life (viz., the 

 creation of organic matter) is derived from the sun in 

 the form of light, the whole of the force of animal life is 

 generated by the katabolic process going on in the 

 body. 



But it will be objected that a certain amount of mat- 

 ter running down can do no more than raise the same 

 amount of matter the same height. The whole force 

 of waste is consumed in repair and nothing is left over 

 for the other activities of the body. This objection is 

 embodied in the second question. The answer to it 

 is (i) that in case of waste tissue, the running down 

 is to a much lower plane (C0 2 and H 2 0) than that 

 from which the lifting took place (food). Therefore 

 the running down of say one pound of tissue to C0 2 

 and H 2 will easily lift one pound of albuminoid food 

 to the plane of living tissue and leave much force over 

 for activities of all kinds. (2) There is also much 

 food— viz., all the amyloids and fats and all the albu- 

 minoids in excess of that necessary for repair — that 

 runs down and generates force without expending its 

 force in lifting at all. 



