mixture A 5 drop- \< ' , l\' Ml. Warm all four tube- to 40" and 

 keep in a water bath at 40 for 10 minutes. Te-t each mixture for 

 -larch i by iodine i and t""r -ngar i b\ Kehling's solution). Results : 

 I >ra\v conclusion- a- t" the influence <>f boiling and of free acid and 

 alkali mi the acti\ity of ptxalin. Also try the action of ptyalin in 

 the -.'/(/. Immerse a te-t-iuhe with a mixture of -larch and saliva 



"ok-d previously to mixing) in ice water and test for sugar later. 

 What i- the influence of teni pcra/nrc on enzyme action? 



Sj. fi-cci^itutii'ii. (.'tilled I lor 2 cc. of tillered saliva in a test 

 tube and add 5 times its volume of <>5'r alcohol. \Vhen the white 

 precipitate < of ptyalin and mucin ) ha- settletl. pour oft the alcohol 

 and dissoke the precipitate in the same amount of water as the 

 \olume of alcohol previously added. Take about 3 cc. of this, add 

 an ei|iial amount of starch paste and place in the water bath at 

 411 Kxamine at interval-, hoe- the starch paste become clear? 

 Test with iodine solution and Fehling's solution. Compare with the 

 preceding experiment. 



S^. \/ ( /-;r\ <>J Starch Hydrolysis :.///; l't\aliii. Mix starch paste 

 and dilute (i: loi tillered saliva as above, warm to 4O : . and 

 keep warm by holding the tube in the hand. At half-minute intervals 

 transfer with a gla-- rod a drop of the mixture to a drop of 

 iodine solution previously placed on a white plate. Xote the pro- 

 gressive change in color reaction. Kxplain. dive the reaction 

 which occurs. 



1 I"' AT-SI'LI I I I Xt, OF Lll'ol.YTir I-T.RMKXTS. 



*j. l.iptts,-. I'-c artificial pancreatic juice made by dissolving 

 ;ui extract ot paiicrea- i commercial pancreatin ) in \<< Xa..L"(). 

 -' ilutit in. 



I'lace in each of two te-t-tubes _> dr ps of neutral olive oil 



5 cc. of i' Na 2 CO : warm and shake. Kcsult ? To one test tube 



add 5 CC. artificial pancreatic juice: to the other, the same, boiled. 



\\ arm and place both in the water bath at 40 . Kxamine at intervals 



minutes. Does emulsification occur in either tube: 



Explain. 



in each of i\\,. h-st-tubes _> dn>p- of olive oil, and 



-hake. . \dd to ,.m- tube 5 cc. jiancreatic extract; to the oilier ; cc. 



pancreatic extract ^r t Tinsly boileil. I'lace at 40 C. After I hour 



h tor -oap a- follows; The cmul-itied oil will separate to a 



I-'"'- 'it at the top of the tube. l\i move some of the relatively 



i li|uid from the bottom of the tube with a long pipette. To* 





