268 A. I. EIXGER AND EMIL J. BAtlMANN 



It is only from these final oxidations that the cells of the body derive 

 their energy. All the changes that the foodstuffs undergo, be it in the 

 process of digestion or later in metabolism, are all aimed to prepare them 

 for the stage in which the cells can utilize them for energy formation. 

 Whether we start with the complex protein molecule, the high carbohydrate 

 molecule or the comparatively simple fat molecule, they must all be 

 ground down in the mill of metabolism to fit the finest meshes of the sieve. 

 They all have to come down to the two carbon stage which is burned with 

 the liberation of heat and energy. 



Fat Formation from Carbohydrate 



That animals can be fattened by feeding them large amounts of carbo- 

 hydrates has been known to stockmen for centuries. Scientific proof for 

 it has been presented during the course of the last century by a number 

 of authors. 10 



The question that confronts us to-day is, how can we picture the trans- 

 fer of the highly oxidized glucose molecule to the oxygen poor fatty acid ? 

 It is chemically inconceivable that there is a direct abstraction of oxygen 

 and that three glucose molecules become converted into an eighteen carbon 

 fatty acid. We must therefore assume that the fatty acids are built up 

 from more elementary compounds. 



When one makes a survey of all the fats known in the animal and 

 plant kingdoms, one is struck by the fact that in no place is there a natural 

 fatty acid to be found that has an odd number of carbons. In milk, for 

 example, there is present a variety of fatty acids. There we find, 



Butyric Acid, CH 3 CH 2 CH 2 COOH (4 Carbons) 

 Caproic Acid, CH 3 CH 2 CH 2 CH 2 CH 2 COOH (6 Carbons) 

 Caprylic Acid, CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 COOH (8 Carbons) 



Capric Acid, CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH,CH 2 CH 2 COOH 



(10 Carbons) 



Laurie Acid, CH 3 CH 2 CH 2 CH,CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 COOH 



(12 Carbons) 



Myristic Acid, CH 3 CH 2 CHoCHoCH 2 CH,CH 2 CHoCH 2 CHo 



CH 2 CII,CH 2 COOH (14 Carbons) 



Palmitic Acid, CH 3 CHoCH 2 CHoCH 2 CH 9 CH 2 CHoCH 2 CH 2 



CH 2 CH 2 CH 2 CH 2 CH 2 COOH (16 Carbons) 



Stearic Acid, CH 3 CH,,CHoCH.,CHoCHoCHoCH 2 CH 2 CHo 



CH 2 CH 2 CH 2 CH 2 CH,CH 2 Cn 2 COOH "(18 Carbons) 



10 A review of the literature may be found in "Die Fette im Stoffwechscl," by A. 

 Magnus Levy and L. F. Meyer, in Oppenheiraer's Handbuch der Biochemie des Menschen 

 und der Tiere, vol. 4, part'l, p. 449, 1908. 



