THE INHERITANCE OF BIOCHEMICAL CHARACTERISTICS 311 



transamination 



aspartic acid 



4-COs 

 +NH, 



fumaric acid 



glutamic acid succinic acid 

 + NH. 



— malic acid 



presence of alcohols, phenols, or aromatic acids, the UDP-glucuronate is 

 diverted from its normal function and the foreign substance is excreted as 

 a glucuronate formed in the following type of reaction 



UDP-glucuronate + ROH > UDP + R-0 -glucuronate 



Bilirubin resulting from the breakdown of haemoglobin in the cells of the 

 reticulo-endothelial system passes into the blood plasma where it circulates 

 in combination with the a^-globulin fraction ; from there it passes into the 

 cells of the hepatic parenchyma which conjugate the bilirubin with glucuro- 

 nic acid and excrete the product in the bile. Furthermore the hepatic 

 parenchyma is the site of considerable protein synthesis, that of the blood 

 plasma proteins. 



The cells of the parathyroid gland show a special type of biochemical 

 differentiation in that they are able to synthesize parathyroid hormone, a 

 true protein hormone which has so far not been isolated in a pure state. 



The pancreatic islets consist of two types of cell differing in their bio- 

 synthetic characteristics : the a-cells which produce glucagon and the 



page 311, diagram, the zoords "unknown intermedi- 

 ate " should be replaced by " carbamyl phosphate ". 



