﻿THE 
  PLANT 
  AS 
  A 
  WOEKING 
  MACHINE 
  

  

  17 
  

  

  plant 
  absorbs 
  food 
  material 
  from 
  the 
  ovule. 
  While 
  the 
  em- 
  

   bryo 
  plant 
  is 
  developing, 
  food 
  material 
  is 
  constantly 
  being 
  

   transported 
  into 
  the 
  grain, 
  or 
  ovule, 
  until 
  finally 
  a 
  relatively 
  

   large 
  amount 
  of 
  food 
  material 
  is 
  thus 
  deposited 
  (fig. 
  12). 
  

   The 
  ripened 
  seed, 
  or 
  grain, 
  consists 
  of 
  the 
  old 
  ovule 
  wall, 
  

   the 
  stored 
  food 
  material, 
  and 
  the 
  embryo 
  corn 
  plant. 
  The 
  

   scale-like 
  bract, 
  or 
  chaff, 
  which 
  surrounded 
  the 
  young 
  ovule, 
  

   often 
  adheres 
  to 
  the 
  ripened 
  gram. 
  In 
  many 
  kinds 
  of 
  plants 
  

  

  starch 
  71.75% 
  

  

  water 
  10.75% 
  

  

  proteins 
  10/ 
  

   oil 
  4.75% 
  J 
  

  

  IV;. 
  12. 
  Grains 
  of 
  indian 
  cum 
  

  

  A, 
  a 
  grain 
  with 
  seed-covering 
  partly 
  torn 
  away, 
  showing 
  the 
  root 
  tip 
  (?) 
  and 
  the 
  

  

  stem 
  tip 
  (s) 
  of 
  the. 
  embryo 
  corn 
  plant 
  within 
  the 
  seed. 
  B, 
  a 
  grain 
  showing 
  the 
  

  

  percentage 
  of 
  different 
  substances 
  that 
  compose 
  it 
  

  

  the 
  ripened 
  seed 
  or 
  seeds 
  may 
  be 
  surrounded 
  by 
  one 
  or 
  more 
  

   structures, 
  the 
  whole 
  then 
  composing 
  the 
  so-called 
  fruit. 
  

  

  14. 
  Seed 
  germination. 
  Seeds 
  may 
  lie 
  dormant 
  for 
  a 
  very 
  

   long 
  time 
  or 
  may 
  grow 
  soon 
  after 
  being 
  formed. 
  Under 
  

   favorable 
  conditions 
  the 
  young 
  plant 
  within 
  the 
  seed 
  bursts 
  

   the 
  seed 
  coat 
  and 
  continues 
  its 
  growth 
  as 
  a 
  new 
  plant. 
  It 
  

   pushes 
  out 
  its 
  root, 
  stem, 
  and 
  leaves 
  and 
  soon 
  assumes 
  the 
  

   appearance 
  of 
  the 
  kind 
  of 
  plant 
  that 
  formed 
  it 
  (figs. 
  13 
  and 
  

   14). 
  In 
  some 
  kinds 
  of 
  plants, 
  when 
  the 
  seed 
  germinates, 
  the 
  

   seed 
  coat 
  remains 
  underground 
  and 
  the 
  stem 
  and 
  leaves 
  grow 
  

  

  