ORGAN THERMOGENESIS 



acid itself is being oxidized and at differential rates. A more 

 modern and perhaps more accurate method of assaying cyto- 

 chrome oxidase involves a spectrophotometric procedure where 

 the cytochrome c substrate is reduced with hydrogen gas and 

 palladium prior to its addition to the reaction system. 



JANSKY: Of course there is a certain amount of autoxida- 

 tion of ascorbic acid in the manometric procedure, but we can 

 avoid it very easily by extrapolating to zero after measuring the 

 oxygen consumption in Warburg flasks containing various concen- 

 trations of homogenate. I would say the spectrophotometric method 

 is probably more convenient except that we cannot easily measure 

 the oxygen consumption. 



201 



