it add a drop of neutral olive oil and shake. Does emulsification 

 occur? CaCl, cannot be used as a soap test here because pancreatic 

 juice gives a precipitate with CaCL. 



c. Milk test. Into each of two test-tubes, a and b, place 5 cc. 

 neutral milk and a drop of litmus solution. To A add 5 cc. neutral 

 pancreatic juice; to B, the same previously boiled. Set at 40 for 

 40 min. Does the litmus become red in one tube? Why? Write the 

 reaction. 



85. Does pancreatic juice hydrolyse starch? Perform an ex- 

 periment to test this. Test also hydrolysis of cane sugar. 



86. Progress of fat-splitting (or lipolysis). Racli ford's experi- 

 ment. Arrange a series of several watch-glasses each containing 

 \ c /c Na,,CO :v Mix in a test-tube 2 cc. neutral olive oil and i cc. 

 pancreatic extract. \Yarm to 40 ; shake the tube, then allow the oil 

 to separate, and transfer a drop by a pipette to the soda-solution in 

 watch-glass I. Again shake and after an interval allow the oil 

 to separate as before and place a drop in watch-glass 2. Repeat 

 this procedure several times. The changes in the oil produced by 

 allowing the lipase to act for progessively longer and longer periods 

 are seen. Note carefully changes in behavior of the oil on passing 

 along the series of watch-glasses. 



D. PROTEIN-STLITTIXG OR PROTEOLYTIC FERMENTS. PROTEASES. 



87. Pepsin. Enzyme active in acid solution. Use an artificial 

 gastric juice made by extracting commercial scale pepsin with warm 



Q.2% HC1. 



Take six clean test-tubes labeled A to F, and place in each a few 

 shreds of fibrin, or strips of hard boiled egg-white. To the tubes 

 add the following: 



a. 0.2% HC1. 



b. Artificial gastric juice. 



c. The same, but previously boiled. 



d. Gastric juice carefully neutralized (using as indicator very 

 weak neutral red solution) with o.2 ( / f KOH added from a pipette 

 drop by drop. 



e. Gastric juice neutralized as in d and then rendered alkaline 

 with an equal volume of i c /r Na,CO,.. 



f. Distilled water. 



Warm and place in a water bath at 40. At intervals note any 

 changes occurring in the digests, especially in b. After forty min- 

 utes test each solution for protein by the biuret test, after removing 



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