STOMACH DIGESTION 71 



SUMMARY 



1. The diaphragm divides the inside of the body into an 



upper cavity called the thorax and a lower one called, 

 the abdomen. 



2. In the abdomen are the organs of digestion. 



3. The lining of the abdomen and the covering of its 



organs is a smooth membrane called peritoneum. 



4. The stomach is a muscular bag lined with mucous 



membrane and covered with peritoneum. In its 

 mucous membrane are glands which produce the 

 gastric juice. 



5. The gastric juice is water containing hydrochloric acid, 



and two ferments. It changes albumin to peptone. 



6. The actions of the stomach may be summed up in three 



things : (i) It is a storehouse in which food is held 

 while being passed on to the intestine in a slow and 

 steady stream. (2) Its peristaltic movements break 

 up the food and mix it with the gastric juice. (3) It 

 digests some albumin by means of the acid and 

 pepsin of the gastric juice. 



7. Every minute or two some of the liquefied food passes 



through the pylorus into the intestine. 



8. In from two to five hours after a full meal the stomach 



is usually empty. 



9. The stomach has no action upon starch or fat, and 



digests only a part of the albumin. 



DEMONSTRATIONS 



35. Show the internal organs of an animal. A frog or a mouse will 

 do ; but a rat, a rabbit, or a cat will be better. 



Always prepare the specimen in private, and leave it before the class 

 only while it is actually being shown. Cover all the parts except those 

 to be shown, and wash away all traces of blood. Any small animal may 



