GROWTH AND CHEMICAL PURITY 267 



of useless materials of all kinds. Just as the kinetic 

 system utilizes carbohydrates, in responding to bacterial 

 foreign proteins, or in muscular work, so additional 

 carbohydrate energy is used in the work of reducing 

 and eliminating excessive food proteins ; and as a con- 



A. B. 



Section of normal adrenal of cat. Section of adrenal of cat after 



injections of leucin. 

 FIG. 63. EFFECT OF LEUCIN ON THE ADRENALS OF A CAT. 



Note the vacuolated space and the disappearance of the nuclei of the cells 

 of B. 



(From photomicrographs, X 1640.) 



sequence, the calories produced by protein digestion are 

 greater than the calories derived from the protein itself. 



(2) Kinetic Activation: If protein, in excess of the 

 body's needs, acts as an adequate stimulus to the 

 kinetic system, the resultant activation would produce 



