GROWTH OF THE BEAN EMBRYO 
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causes the cotyledons to spread apart, exposing the plumule 
(plum'ul: Latin, plumula , feather) to the air and light. At 
the same time the cotyledons begin to turn green, thus 
serving as leaves till the leaves of the plumule have developed. 
So the plumule is protected and given a chance to grow under 
good conditions. As soon as the food in the cotyledons is 
absorbed by the young plant, they shrivel and drop off. 
Left, root free; center, root branched, hypocotyl developed and show¬ 
ing the arch, cotyledons split apart, and plumule; right, young bean plant 
showing shriveled cotyledons, and first true leaves. 
The young bean plant is known as a seedling, while it is 
dependent on the store of food in the seed. 
In the course of a few weeks a bean plant is large enough to 
produce blossoms which develop into pods containing seeds, 
thus completing the life cycle. The use of the seeds to the 
plant is simply to provide for other plants of the same kind, 
and to insure a supply of food for the early life of each. 
Man, however, hasTearned to take advantage of this habit 
