FUNCTIONS OF THE KIDNEY 



215 



Acids. — Chlorides, phosphates and sulphates. Sulphur 

 is also excreted in a less oxidised form of unknown 

 constitution — neutral sulphur. 



Average Constitution of a Daily Output of Urine 



Functions of the Kidney 



The functions of the kidney are three : — 



1 . To remove waste products from the blood ; 



2. To keep the volume and sahne content of the blood 



constant ; 



3. To keep the reaction of the blood constant. 



In considering the manner in which urine is formed it 

 must be remembered that although we use the word 

 secretion in this connection, the kidney difl'ers from a 

 secreting gland, such as a gastric gland, in the following 

 fundamental respects. 



1. Developmentally it is of mesodermal origin, while 

 most other glands are formed by invagination from the gut. 



