FATS AND RELATED SUBSTANCES. 57 



in the processes syntheses and oxidations both must be con- 

 cerned since the fat molecules are more complex than those of 

 the carbohydrates. 



It is further likely that protein compounds are important 

 factors in fat production. Many writers have indeed assumed 

 that we have in the breaking down of protein molecules the 

 chief sources of fats, but this view has been strongly com- 

 bated. Indirectly the transformation may follow in this way : 

 It is known that sugars are formed as cleavage products 

 of albumins in the ordinary katabolic processes of the body 

 and possibly a portion of the sugars thus formed may be then 

 built up to produce fats. 



The existence of the substance known as adipocere has 

 long been held to furnish a pretty strong proof of the produc- 

 tion of fatty acids from protein. This adipocere or cadaver 

 wax is often found in large masses in old cemeteries and 

 consists of fatty acids, calcium and ammonium soaps in the 

 main. It is held that this substance could not possibly have 

 come from the small amounts of fat ordinarily present in 

 cadavers but must have been produced from the muscular 

 portions of the body. This view has met with objections, 

 however, and attempts are made to account for the develop- 

 ment of the adipocere in other ways. 



In the body fats constitute a reserve material in which poten- 

 tial energy is conveniently stored up. In sickness or in wast- 

 ing diseases where there is a partial or complete failure in 

 nutrition this fat is called upon to supply the needs of the 

 body. The fats are oxidized while the muscular tissue is 



preserved. 



PHYSIOLOGICALLY IMPORTANT FATS. 



STEARIN or TRISTEARIN, C 3 H 5 (C 18 H 35 O 2 )3. This is a 

 simple fat which does not occur in nature unmixed with 

 other fats. When separated in purest possible condition it 

 shows a melting point of 55 to 58. It is the hardest of the 

 common simple fats and apparently the least soluble in alcohol 

 or ether. It may be separated in the form of rectangular 



