PART II 
PLANT BIOLOGY 
CHAPTER XV 
THE LIFE OF FLOWERING PLANTS 
183. Introduction. — The plants that we all know and 
admire best are those that at some time in their lives produce 
beautiful flowers. These flowers, however, are only tem¬ 
porary structures which drop off as soon as their work is 
done. They are the special adaptations of the plant for 
producing more plants. The parts of the plant which have 
to do with its own life and well-being have adaptations too, 
many of which are as interesting as the flowers. 
These parts of a plant may be divided into two groups: 
those that are adapted to doing their work in the air, such 
as the leaves and the stem, and those which do their work 
in the soil, such as the roots and root hairs. In studying 
these parts of some of our familiar plants we shall give most 
attention to those structures which require explanation as to 
how each does its share in helping the whole plant to live. 
All these structures, the flower, the leaves, the stem, and 
the roots, are common to most plants. Each structure as¬ 
sumes its part in carrying on the life processes of the plant 
which could not live successfully without them all. A 
plant is an organism, and its several parts are organs or 
groups of organs (page 7). 
We thus begin our study of plants with their special 
adaptation for their work which is just the way that we began 
our study of animals. 
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