

766 A MANUAL OF VETERINARY PHYSIOLOGY 



a wet substance at the relatively low temperature of the body. The 

 oxidations occurring in the living cell are now believed to be due to 

 the agency of ferments, described above as oxidases. These are 

 contained in the substance of the protoplasm. Oxidases are capable 

 of regulating their own activity, instantaneously and enormously 

 increasing oxidation, as during muscular contraction, or just as 

 instantaneously reducing it to the working minimum when an excess 

 is no longer required. Nor is the action of oxidases confined to 

 utilising the free oxygen brought in by the blood. They can unlock 

 oxygen from oxygen-yielding compounds, and there appears little 

 doubt that it is in some such way that the carbohydrate material in 

 muscle is burnt, and heat and movement produced. 



The action of autolytic enzymes has been referred to at p. 372. 

 These are found very generally distributed in the tissues. 



A classification of the body ferments is not possible at present. 

 In the table on p. 765, from Howell, those principally employed in 

 digestion and nutrition are tabulated. 



