2.5 CLASSIFYING PLANTS
A key for classifying plants is shown on the next page. The same key is given in written form in
the box below. Study both versions of the key before you read on.
Biologists classify plants into four
main divisions: mosses, ferns,
conifers and flowering plants. The
flowering plants are divided into
two classes, monocots and dicots.
Mosses are plants that have no
proper system of roots and stems.
Because they have no stems to
carry water, they must grow close
to a wet surface. The most
common examples are the green
mosses that grow on damp soil, on
rocks close to streams, and on the
bark of well shaded trees.
A simple key to plants
1. Plant has a system of roots and stems
Plant has no proper roots and stems
GO TO 2
MOSS
2. Plant has fruits
Plant has no fruits
GO TO 3
FERN
3. Plant has flowers
GO TO 4
Plant has no flowers, fruit is woody cone CONIFER
4. FLOWERING PLANT
Spear-shaped leaves with parallel veins
Variable leaves with a network of veins
MONOCOT
DICOT
Ferns are plants that have proper roots and stems, but do not bear fruits. There are many
different kinds of ferns. They often grow in damp places, and have very beautiful leaves with
many parts.
Mosses covering stones
Ferns
Conifers are plants with no flowers, but they have fruit in the form of
woody cones. Almost all conifers are trees with tough, needleshaped leaves. The most common conifers are the many different
kinds of pine trees. They often form huge forests, especially in cold
countries. Pine trees are used for timber and for making paper.
Pine tree
Flowering plants are much the most common kinds of plants. Almost all the plants we will study
in this book are flowering plants. They are divided into two classes: monocotyledons (or
monocots for short) and dicotyledons (or dicots).
Monocots have spear-shaped leaves in which the veins are nearly parallel to one another. The
seeds contain only one fleshy seed-leaf (cotyledon). We will talk more about seeds in Chapter 5.
The monocots include our cereal crops, grasses and bamboos, palm trees and bananas, and a
group of plants called lilies.
Dicots have leaves of many different shapes in which the veins form a network. Their seeds
contain two fleshy seed-leaves (cotyledons). Many common bushes and trees are dicots; so are
most of the plants we get our fruits and vegetables from.

1. Do all monocots have fruit? (Clue: use the key).

3. Is a fern a monocot or a dicot?

2. What plants have (i) roots and stems but no fruits,
(ii) roots, stems and fruits but no flowers, (iii) two
cotyledons?

4. Use the key to list as much information as you
about all plants that are dicots.
2 – 5a
A simple key to plants
PLANTS
plants have a system of roots and stems
plants have fruits
plants have no flowers,
fruit forms woody "cones"
CONIFEROUS PLANTS
eg pine trees
plants have no proper system of roots and stems
MOSSES
eg mosses
plants have no fruits
FERNS
eg ferns
plants have flowers
FLOWERING PLANTS
leaves spear-shaped with parallel veins,
seeds have one cotyledon
MONOCOTS
eg grasses. lilies, bananas, palms
Pine tree
and cone
2 – 5b
leaves variable with network of veins,
seeds have two cotyledons
DICOTS
eg yams, tomatoes, hibiscus and many bushes and trees