Download Plant Structures

Plants
are cool!
Plants are multicellular organisms that make their own food. Like
animals, plants have specialized structures that help them carry out
their life functions.
Water+CO2=
O2+ energy
This process is
called
photosynthesis!
The main parts of a plant are the leaves, stems, roots, and flowers. These
parts are labeled in the diagram below.
The leaf is the plant structure that makes most of a plant's food. Leaves are usually
green because the cells in leaves contain large numbers of chloroplasts. Recall that
the chloroplast is the organelle that carries on photosynthesis, the process of
making food.
Leaves are
the plant
structures that
make glucose!
The leaf is the plant structure that makes most of a
plant's food. Leaves are usually green because the
cells in leaves contain large numbers of
chloroplasts. Recall that the chloroplast is The
organelle that carries on photosynthesis, the
process of making food.
The stem is the plant structure that holds up the leaves. Leaves
need sunlight in order to make food. The stem holds the leaves in position to capture as much of
the Sun's energy as possible.
The stem also is able to grow, making the plant taller and wider. The stems of trees can grow very
tall. The walls of the cells in the stem, or trunk, of a tree contain a compound called lignin, which
makes the cell wall tough and strong.
A stem
supports
the leaves
of the plant.
The root of a plant is the structure that anchors the plant in the soil and absorbs
water and nutrients. In some plants, roots also store food for the plant. When you
eat a "root vegetable," such as a carrot, you are eating food stored by the plant.
Roots anchor the
plant and also
absorb the
nutrients!
There are two kinds of root systems, fibrous roots and taproots. As you can see in the drawing below,
a taproot system has one main, deep root, with smaller roots branching from it. Trees all
have taproots. A fibrous root system has many roots that are the same size. There is no main root.
Grasses have fibrous roots.
We have two
types of roots
and they are tap
and fibrous
roots.
Plants contain vascular tissue, made up of cells that form tubes through which
water and food move in the plants. These tubes form a continuous system in the
plant. Water enters the plant at the roots, moves up through the root and the stem,
and into the leaves. Food made in the leaves moves down through the stem to the
root, where it is stored.
Vascular
tissue in
plants move
water and
food in
plants.
The flower is the reproductive structure of a plant. The male part of a flower is the
stamen. The female part is the pistil, which contains the ovary. When a plant
reproduces, the ovary becomes the fruit, which contains the seeds.
The ovary of
the plant
becomes the
fruit we eat!
The main purpose of a leaf is to make food for the plant. But in some
plants, leaves have special functions and look very different from other
leaves. The spines of a cactus are actually modified leaves. However,
these leaves do not carry out photosynthesis. Their shape saves water for
a plant that grows in a desert environment.
My spines
save water!
The stem of a cactus is different from the stems of other plants. The
fleshy stems of a cactus are specialized to store water for the plant.
Also, because the leaves do not carry out photosynthesis, the stems of a
cactus are green and make food for the plant.
The stems in the
cactus make
food for the
plant!