METABOLISM. 51 
inconclusive, the formation of fat from proteids has not yet been 
disproved and has weighty direct evidence in its favor, while the 
facts that sugar may be formed from proteids, and that carbohy- 
drates are certainly a source of fat to the animal organism are 
strong additional arguments in favor of its possibility. 
Schematic Equations —Chauveau and his associates * whose 
views regarding the functions of the carbohydrates in the body 
have already been mentioned, regard the katabolism of the proteids 
as taking place in three stages. The first consists of the splitting 
off of urea with production of carbon dioxide, water, and fat, accord- 
ing to the equation: 
A(CrpHy12N 10228) oe 1390, 
(Stearin) : 
= 2(C7Hy 1404) + 36CON,H, + 138CO, + 42H,0 +28, 
The resulting fat is then, according to Chauveau, further oxi- 
dized in the liver, yielding dextrose, in accordance with the equation 
already given on p. 38, viz., 
2Cq¢H 109+ 670, = 16C,H,.0, + 18CO, + 14,0, 
and the dextrose is finally oxidized to carbon dioxide and water. 
Another equation representing the katabolism of proteids is that 
proposed by Gautier, which regards the first step in the process as a 
combined hydration and cleavage with the production of urea, fat, 
dextrose, and carbon dioxide, as follows: 
2(Cy.H12N 10225) ake 28H,0 
(Tripalmitin) 
=18CON,H,+2 
C5,H gO, + C gH 120.4 18CO,+8,. 
It may be assumed that these authors regard the above equa- 
tions simply as schematic representations of the general course of 
proteid metabolism and do not intend to imply that there are no 
intermediate stages in the process. Interpreting them in this 
sense, we have good reasons for believing that the facts which they 
represent are qualitatively true. A chemical equation, however, 
expresses not merely qualitative but quantitative results. If the 
above equations have any significance beyond that of the mere 
verbal statement that fat and sugar are products of proteid meta- 
*(Cf, Kaufmann, Archives de Physiol., 1896, p. 341. 
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