74 



BOTANY 



The use of the endosperm to the corn; A, seedhngs 

 without endosperm; B, seedlings with starch in 

 place of endosperm; normal seedlings at the 

 center. 



Make drawings at the end of 

 two weeks to explain your re- 

 sults. Of what use is the 

 endosperm? Can the seed- 

 ling make use of the food 

 supply given it in the corn- 

 starch paste ? 



Other Foods in Corn 

 Grain. — Other foods be- 

 sides starch and sugar are 

 present in the corn grain. 

 A test for proteid shows 

 that a considerable 

 amount of this food is pres- 

 ent. Oil also is found. In 

 the sweet corn that we eat 

 water forms a very large 

 percentage of its composi- 

 tion by weight. This is 

 true of most plant and animal foods that are eaten in a fresh state. 



Fate of the Parts of the Em- 

 bryo of the Bean, the Pea, and 

 the Corn. — If the above experi- 

 ments with reference to the ger- 

 mination of peas, beans, and corn 

 have been carefully obser^^ed, you 

 have by this time reached veiy 

 definite conclusions regarding the 

 use of each part of the seed (or 

 grain) to the young plant. In 

 all specimens the hypocotyl is 

 found to give rise to the root 

 system of the young plant (and 

 in the bean to part of the stem), 

 while the part we call epicotyl 

 forms the leafy shoot. The func- 

 tion of the cotyledons differed in 

 all specimens. In the bean they 



were carried up above ground; The germination of a grain of corn. 



