DIGESTION. 



33 



the secretory activity of the pancreas is established, the granules disappear, 

 and the inner granular layer becomes reduced to a very narrow border 

 while the outer zone increases in size and occupies nearly the entire cell. 

 During the intervals of secretion, however, the granular layer reappears 

 and increases in size until the outer zone is reduced to a minimum. It 

 would seem that the granular matter is formed by the nutritive processes 

 occurring in the gland during rest, and is discharged during secretory 

 activity into the ducts and takes part in the formation of the pancreatic 

 secretion. 



FIG. 4. 



d 



One saccule of the pancreas of the rabbit in different states of activity. A. After a 

 period of rest, in which case the outlines of the cells are indistinct, and the inner zone, 



VlP Dart nf thp rells (a.\ next tVlf llimpn ( /~\ ic KrrQr1 Qnrl fill<H wit-Vi finp> crrarni1p 



Book of Physiology, after Kuhne and Lea 



The pancreatic juice is transparent, colorless, strongly alkaline and viscid, 

 and has a specific gravity of 1.040. It is one of the most important of the 

 digestive fluids, as it exerts a transforming influence upon all the classes of 

 alimentary principles, and has been shown to contain at least three distinct 

 ferments. It has the following composition : 



COMPOSITION OF PANCREATIC JUICE. 



Water 900.76 



Albuminoid substances 90.44 



Inorganic- salts 8.80 



1000.00 

 The pancreatic juice is characterized by its action: 1st Upon starch. 



