DIGESTION 25 



37. Digestion of water and minerals. Water and min- 

 erals need no digestion, but are taken up at once by 

 the blood tubes. Water is always being poured into the 

 mouth, stomach, and intestine by the glands, but is soon 

 taken up again by the blood tubes. In all, about twelve 

 quarts of water enter and leave these parts each day. As 

 only two or three quarts are swallowed each day, the same 

 water is used over and over again. 



SUMMARY 



1. Making food a liquid so that it can reach and feed the 



cells of the body is digestion. 



2. Cooking begins digestion by softening the food. 



3. The mouth grinds the food and mixes it with the 



saliva which changes some starch to sugar. 



4. The stomach mixes the food with the gastric juice, 



and continually stirs it about. The gastric juice 

 dissolves some of the albumin to rjeptone. 



5. In the intestine the bile and par>-qa,tic jmc.fr ^hanpre 



albumin to peptone and starch to sugar, and break 

 the fat into fine particles. 



6. Digested albumin and sugar soak into the blood tubes 



and are carried to the liver. Digested fat soaks 

 into the lacteals, and is emptied into the blood 

 stream in the neck. 

 /. The liver makes the ajhiimjrijLpart f tligJlklgd- 



8. The liver changes the sugar back to a form of starch 



and oxidizes it, producing heat. 



9. The liver also strains out poisons from the blood. 



10. Digested fat is carried to the lungs, and is there 



oxidized. 



11. Water and mineral substances enter the blood without 



being digested. 



