CHAPTER IX 

 PANCREATIC DIGESTION. BILE 



Pancreatic Juice 



A solution of pancreatic ferments may be prepared by ex- 

 tracting a pig's pancreas with glycerine or with water contain- 

 ing chloroform. For laboratory purposes it is, however, more 

 convenient to use a solution of commercial pancreatic powder. 



I. Composition of Pancreatic Juice. 



a. Natural pancreatic juice contains small amounts of pro- 

 teins and other organic substances. 



b. Inorganic salts, chiefly sodium carbonate. 



c. Ferments. The active pancreatic juice contains three 

 important enzymes : trypsin, amylase, and lipase. 



II. Digestive Action. 



a. On proteins. 



Prepare four test tubes as follows : 



1. 5 c.c. neutral pancreatic solution. 



2. 5 c.c. neutral pancreatic solution + 2 drops, saturated so- 

 dium carbonate solution. This gives a concentration of about 

 0.2% sodium carbonate. 



3. 5 c.c. neutral pancreatic solution -{- 3 to 4 drops of 10% 

 HC1. This gives a concentration of about 0.2% acid. 



4. 5 c.c. neutral pancreatic solution + 2 drops saturated 

 sodium carbonate solution, boil thoroughly 3 or 4 minutes and 

 cool. 



To each tube add a Mett tube as described under " Gastric 

 Digestion ' ' and incubate until the next period. 

 Examine the tubes and tabulate results. 



Trypsin acts best in a silghtly alkaline solution. It also will 



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