308 ESSENTIALS OF BOTANY 
processes, and conducting it to all parts of the plant body to 
maintain growth in the tissues. Some of the plant food is 
carried to the rudimentary flowers to form pollen and ovules 
Fie. 221. Effect of Cultivation 
on Root? of Carrot. 
A, root of wild carrot, annual or 
biennial; B, root of same spe- 
cies cultivated, biennial. The 
wild form can be changed in 
four generations into the culti- 
vated form. 
together with the structures 
which bear them. Another por- 
tion of building material is later 
carried to the cones of the year 
before, to maintain growth in the 
newly fertilized ovules! Still 
another portion goes to the 
two-year-old cones to complete 
their growth. And it must be 
remembered that each growing 
and dividing cell is not a simple 
sac, filled with formless proto- 
plasm, but a very complicated 
structure with many highly spe- 
cialized parts. 
It requires considerable knowl- 
edge of chemistry to follow even 
the principal steps in the trans- 
formations which food materials 
undergo within the plant body. 
Photosynthesis apparently often 
results in sugar, which is quickly 
changed into starch, then back 
into sugar, for transference’ to 
more remote parts of the plant. Here again it is trans- 
‘formed (in root, stem, or fruit) into the starch or oil which 
constitute the principal reserve material of most plants. 
1 Fertilization in the pine occurs about thirteen months after pollination. 
See Bergen and Davis’ Principles of Botany, p. 374. 
2 This is really part root and part hypocotyl. 
