LABORATORY MANUAL 37 



DIRECTIONS FOR WORK : 



(1) To test for proteids: Add a little nitric acid to crushed 

 seeds; after a minute rinse with water and add a few drops 

 of ammonia solution. A yellow color where the acid acted 

 shows that a proteid is present. The deeper the color, the 

 greater the quantity of proteid. 



(2) To test for starch. Break open the seeds (if whole) 

 and boil them. Then add a drop of iodine to the seed or 

 even to the water in which it was boiled. A dark blue 

 color shows the presence of starch. 



(3) To test for oil. Place the seeds between two pieces of 

 soft paper and press them with a warm iron. After a little 

 while, remove the iron, shake off the seed, and hold the 

 paper toward the light. A translucent spot (in this case, a 

 grease spot) shows oil to be present. 



Effect of Application of 

 Seeds ( Nitric Acid Iodine Warmth and Pressure 



\ Ammonia 

 Oatmeal 

 Wheat Cereal 

 Peanuts 

 Beans 

 Peas 



Corn (popped) 

 Any nut 



EXERCISE XXIX (Textbook 312) 

 STUDY OF A FLOWER 



MATERIALS: Flowers, like the tulip or Easter lily, for a 

 first exercise; needles in wooden handles or long slender 

 pins; a sharp knife. (Sweet peas, primroses, or geraniums 

 [single] are a little less simple and might be substituted 

 or taken later.) 



