C H A P T E R
Reflecting
Questions
What are the parts
of a plant and how do
they function?
How do water and food
move around in a plant?
How does a plant grow?
520
14
Plant Characteristics
and Functions
Few animals live past 100 years, but
advanced age is not at all unusual in
the plant kingdom. Unlike animals
such as humans, plants continue to
grow throughout their entire life
cycle. This ability is only one of the
identifying characteristics of plants.
Plants can be thought of as selfreliant chemical factories. For
example, the appearance of new
leaves in the spring is evidence that a
living tree can collect materials from
its external environment and use
those materials to manufacture the
new substances that it uses for
growth. Perhaps the most important
substance used by trees and other
plants is the food they produce called
glucose. The tree’s cells release
energy from glucose by cellular
respiration, and use the energy to
build new substances. The tree uses
these new substances for life
functions, such as repair and growth.
In this chapter, you will learn how
plants use materials from the
environment for their growth and
survival. Some plants, such as mosses
and liverworts, do not have a
sophisticated system of transporting
water and nutrients within their
bodies. Other plants, which make up
the greatest number of species and
the greatest biomass on Earth, have
systems that transport water and
nutrients between the parts of the
plant. The majority of plants have
developed specific structures such as
leaves, stems, and roots to collect
materials from the environment,
manufacture food for the plant’s
growth, and transport materials
throughout the plant. Materials are
transported through specialized cells
that are found in each of the leaves,
stems, and roots.
The rings on the tree stump in the
large photograph on the next page
show that the tree was 600 years
old when it was cut down. It is not
necessary to cut down a tree in order
to measure its age, however — a core
sample can be taken instead.
Chapter
Contents
14.1 Classifying Plants
522
Investigation 14-A: Comparing
Monocots and Dicots
526
14.2 Vascular Systems
531
14.3 Structure and Function
535
MiniLab: Plant Transpiration
537
Investigation 14-B: Observing
Stomatal Action
538
Thinking Lab: Counting
Growth Rings
541
MiniLab: Viewing Root Hairs
and Estimating Their Area
544
Investigation 14-C: Viewing
Structures, Inferring Functions
546
521