ABSORPTION OF FOOD 
413 
-shi-), 'potassium (po-tas'si-um), and phosphorus (fos'for-us) 
are taken in with our food. They are useful to the body. 
A small amount of iron is also contained in food and water 
and becomes a part of the red blood cells. 
STUDENT REPORT 
Where the Food Is Digested 
In the 
Cell 
In the 
Leap 
Primitive 
Digestive 
Tube 
Stomach 
Mouth 
Digested 
by 
. Enzymes 
Paramecium . 
Hydra . . . 
Frog .... 
Man, etc. . . 
Bean .... 
Yeast .... 
LABORATORY STUDY 
Study food and food tests. Artificial gastric juice is easily prepared 
by taking \ gram of pepsin, cc. of strong hydrochloric (hi-dro-klo'- 
rik) acid and adding 50 cc. of water. Take white of egg that has been 
cooked and subject it, in a test tube, to the above mixture. A variety of 
tests should be made, with and without heat (100° F.), with and without 
the acid. Pancreatic juice is made by uniting 15 grams sodium (so'- 
dl-hm) carbonate (kar'bbn-at), 5 grams pancreatin (p&n'kre-a-tin), and 
100 cc. water. The action of this fluid may be tested as above on the 
fats, as olive oil; on starch, as flour; and on proteins, as raw lean meat 
or milk. Also examine several of the common articles of food to deter¬ 
mine to what class of foodstuffs they belong. 
329. Absorption of Food. — The absorption of food in man 
and animals is the process of taking the digested foods 
from the alimentary canal into the blood. Practically no 
food is absorbed in the mouth or esophagus, and but little 
in the stomach. 
The absorption of food from the intestinal canal is done 
by small folds in the lining of the small intestine. To the 
