226 DIGESTION AND ABSORPTION 



fats, pancreatic juice changes them into soft soaps and fatty acids. Fat in this 

 form may be absorbed. (See page 306, Civic Biology.) 



Conclusion. — 1. What conditions are necessary to make an 

 emulsion ? 



2. What is the effect of pancreatic fluid on oils? 



Problem 192: To study the effect of artificial pancreatic 

 juice on protein. 



Materials. — • Artificial pancreatic juice, caustic soda, copper 

 sulphate. 



Method. — Using artificial pancreatic juice instead of a mixture 

 of hydrochloric acid and pepsin, carry out an experiment as de- 

 scribed for tube No. 3 of Problem 188. 



Observations. — Was any of the white of egg digested ? 



Conclusion. — Make a table to show the effect of pancreatic 

 juice on nutrients. 



Problem 193 : To find one action of bile. 



Materials. — Ox gall or bile, olive oil, parchment paper, funnels. 



Method. — Take two funnels, place parchment paper in each. 

 Moisten one paper with bile, the other with water. Then place 

 an equal amount of olive oil in each funnel. 



Observations. — Through which funnel does the oil pass more 

 freely ? 



Conclusion. — What effect might bile have on the wall of the 

 intestine ? 



Summary of the Uses of Human Food Tube and Glands 



Digestive System of Man 



f Teeth 

 Mouth < Tongue 



I Glands — saliva — digests starch 

 Pharynx. 

 Esophagus 

 Stomach — glands — gastric juice — digests proteins — dissolves Ume salts 



Liver — bile — helps fat absorption 



f starch 



Pancreas — pancreatic juice — digests | protein 



I oils 



Absorption of digested foods 



Large intestine — slight absorption of soluble foods and wastes 



Alimentary 



Canal 



and 



Digestive 



Glands 



Small intestine — glands 



