320 PHYSIOLOGICAL CHEMISTRY 



act in neutral or even faintly acid solution. It is, of course, de- 

 stroyed by boiling. 



2. On Fats. Pancreatic juice contains a lipase. To 5 c.c. 

 milk add 3 or 4 drops of litmus or lacmoid solution, and enough 

 sodium carbonate to produce a blue color (no more). Add the 

 amount of pancreatic powder which can be taken up on a knife 

 point. Keep at body temperature for some time. The color 

 turns pink, since fats are split, fatty acids set free, and the reac- 

 tion becomes acid. If the test is allowed to stand too long, an acid 

 reaction will result from the souring of the milk (production of 

 lactic acid from lactose). The bile greatly favors the digestion 

 of fats by pancreatic juice. 



. On Starch. The pancreatic juice contains an amylase, which 

 soon becomes inactive in artificial preparations. 



Products of Pancreatic Digestion of Proteins. 



Kecall the results of your work on products of pancreatic 

 digestion under amino acids. 



Intestinal Juice 



The succus entericus or intestinal juice plays an important role 

 in digestion. For a description of the intestinal ferments and 

 their action, the student is referred to the discussion of this sub- 

 ject in the text. 



Bile 



The bil-e is secreted by the liver into the gall bladder and 

 thence delivered to the intestine. Bile plays an important part 

 in digestion. Note the green or yellow color. Test the reaction 

 with litmus. It usually is neutral or slightly alkaline. 



Composition. 



Inorganic Material. The bile contains various inorganic sub- 

 stances, among them the phosphates of calcium, magnesium and 

 iron; sodium and potassium, both in the form of chlorides 

 and combined with bile acids to form bile salts; sulphur and 



