EXERCISE 19 



Object. To make a study of the physical parts of corn 

 kernels. To show the differences in texture in the different 

 parts of the same kernel. To show the location of color 

 in yellow, white, and red kernels of dent 

 corn. 



Explanation. There are six distinct 

 types of corn: dent, flint, soft, sweet, 

 pop, and pod. Dent corn is the type 

 most generally grown. 



There are four distinct parts of the 

 corn kernel. They are the seed coat, 

 aleurone layer, endosperm, and embryo. 

 The seed coat or hull is a thin outer layer 

 covering the entire kernel. It serves as 

 a protection for other parts of the kernel 

 and constitutes about 7 per cent of the 

 kernel. The aleurone layer lies just 

 under the seed coat and serves as a second covering for 

 the kernel. It constitutes about 10 per cent of the corn 

 kernel. The endosperm comprises the greatest part of the 

 corn kernel. It is composed largely of starch and is a 

 source of food supply for the young plant just after 



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FIG. 6. A corn ker- 

 nel, a, crown starch ; 

 6, hull ; c, horny 

 starch ; d, shoot of 

 embryo ; e, germ ; 

 /, root of embryo ; 

 g, tip cup. 



