CHAPTER XV 

 METABOLISM NUTRITION ANIMAL HEAT AND FORCE 



Action of glandular cells Metabolism, anabolism and katabolism General nutrition 

 Luxus-consumption Isodynamic values of foods Animal heat and force Limits of 

 variations in the normal temperature in man Variations in different parts of the body 



Variations at different periods of life Variations at different times of the day Influ- 

 ence of exercise etc., on the heat of the body Influence of the nervous system on the 

 production of animal heat (heat-centres) Mechanism of the production of animal heat 



Equalization of the animal temperature Relations of heat to force. 



METABOLISM, ANABOLISM AND KATABOLISM 



THE constant change going on in the constituents of the body is 

 called metabolism. A part of this process consists in a repair of the 

 tissues and is known as anabolism. This repair is made necessary by 

 a constant change of the constituents of the organism into effete 

 matters. This change is called katabolism. 



In the changes that are involved in metabolism, inorganic as well as 

 organic matters participate. Organic matters, indeed, are never free 

 from inorganic substances ; and the latter accompany organic matters 

 in the changes incident to nutrition. The organic constituents of the 

 body are almost all included in the proteids. 



The inorganic matters number about twenty-one. The most impor- 

 tant of these is water. This is found in all tissues without exception. 

 It is discharged from the body as water and is useful in carrying off 

 effete matters in solution. It is introduced in all forms of food and 

 drink. In addition, it is formed in the body by the union of hydrogen 

 with oxygen, this process contributing to the production of animal heat 

 and force. The water thus formed a.-d discharged from the body may 

 properly be regarded as an excretion. 



Many saline compounds exist in the body in solution in water. 

 These are essential to nutrition. They are introduced from without, 

 exist in the body united with organic matters and are discharged in 

 the form in which they entered. 



Proteids, as proteids, are not discharged from the body in health. 

 They are converted into excrementitious matters and as such form part 



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