Classifying
Plant Groups
4.1
Organization
Plants
Vascular
Nonvascular
Seed
Seedless
Angiosperms
Ferns and
related plants
Gymnosperms
Mosses and
related plants
Learning Targets
I
can understand plants are classified
according to similar structures
 I can explain the difference between
vascular and nonvascular plants
 I can compare and contrast seed plants
and seedless plants
 I can define angiosperm, gymnosperm,
dicot and monocot
How are plants Classified?
 Scientists
have discovered over 300,000
different kinds of plants
 About
1,000,000 plants may exist that
have not been found and named
 Scientists
believe these plants live in the
tropical rain forest
Classification
 Plants
are classified according to whether
they have body parts such as seeds,
tubes, roots, stems, and leaves
 There



are 3 main groups of plants:
Seed Plants
Ferns
Mosses
History of Classification
 The
Greek philosopher Aristotle first
classified plants and animals
 Carl
Linnaeus then developed a
classification system still in use today
 All
living things have a scientific name
which consists of the genus and species
Vascular Plants
 Vascular
means “vessel” or “tube”
 Vascular
plants have tube-like cells
 Seed
plants and ferns are examples of
vascular plants
Vascular (cont.)
 These
tube-like cells form tissue called
vascular tissue
 The
tissue forms tubes that transport food
and water through the plant
 Vascular
plants have well-developed
leave, stems, and roots
Vascular Tissue
 This

tissue is important in two ways:
First, it allows food and water to be
transported over a distance
 Plants
can grow where water is not always
present

Second, vascular tissue is thick and provides
support for the plant
 This
allows the plant to grow taller
Nonvascular Plants
 Nonvascular
plants do not have tube-like
cells
 These plants are short and must have
constant contact with water
 They do not have tubes to transport water
or support them
 They do not have true leaves, stems, or
roots
 Mosses are nonvascular plants
Vocabulary
 Vascular
Plant
 Nonvascular Plant
 Self
Check Questions, pg. 69
 #1-5
 COMPLETE SENTENCES
What are
Seed Plants?
4.2
What are Seed Plants?
 Seed
plants use seeds to reproduce
A
seed is a plant part that contains a
beginning plant and stored food
 The
beginning plant part is called an embryo
 Seeds
have a seed coat, which holds in
moisture
Seed Plants (cont.)
 When
conditions are right, the embryo
grows into a full-sized plant
 Seed
plants are the largest group of
plants
 They
are divided into 2 sub groups:
flowering and nonflowering plants
Angiosperms (Flowering)
 Most
species of plants are angiosperms
 A capsule, or fruit, protects the seeds of
angiosperms
 The fruit forms from part of the flower
 Angiosperms are divided into two groups:


Dicots
Monocots
Dicots
 Have
2 seed leaves (on the embryo)
 Crisscross
 Most
pattern of veins on leaves
flowering plants are dicots
 Examples:
sunflower
fruits, vegetables, rose,
Monocots
 Have
only one seed leaf
 Parallel
 Mostly
pattern of veins on leaves
grasses, but some flowers
 Examples:
orchid
grass, corn, wheat, rice, lily,
Gymnosperms (Nonflowering)
 Do
not produce flowers
 Seeds
are not surrounded by a fruit
 Seeds
are produced inside cones
 Example:
seeds of pine trees form on the
scales of cones
Conifers

The major group of gymnosperms

Cone-bearing plants

Woody shrubs or trees

Main source of paper and wood products

Examples: pine, spruce, fir
Conifers (cont.)
 Most
have green leaves all year long
 They are called evergreens
 Leaves are shaped like needles
 Makes it easier to live in dry places and
store water
 Grow in places where other plants cannot
grow (shallow, rocky soil and along coast)
Vocabulary
 Angiosperm
 Embryo
 Seed
Gymnosperm
Conifer
Monocot
 Dicot
 Self
Check Questions, pg. 73 #1-5
 COMPLETE SENTENCES
What are
Seedless
Plants?
4.3
Ferns (Vascular)
 Largest
group of seedless plants
 Well-developed leaves, stem, and roots
 Mostly tropical plants
 Leaves are called fronds (large and flat)
 Fronds uncurl as they grow
 Sori are clusters of reproductive
cells(spores)found on the underside of
fronds
Spores
 Spores
are the reproductive cells of ferns
and mosses
 After they are released, spores must land
in a moist place or they will dry out
 Spores that drop in a moist place will have
produce a tiny plant
 The plant must have constant moisture to
grow
Spores vs. Seeds
 Spores
must have moist landing and
constant water source
 Seeds
have a seed coat to constantly
deliver food and water
 Seeds
can survive longer than spores in
dry conditions, which is why there are
more seed plants in the world
Mosses (Non-Vascular)
 Reproduce
by spores
 Simple leaf-like and stem-like parts
 No vascular tissue to transport water and
food, so they must live in moist, shady
area (wet soil)
 Have root-like threads called rhizoids
 Mosses look like little trees and often form
carpet-like mats on the forest floor
Vocabulary
 Frond
 Sori
 Spore
 Rhizoid
 Self
Check questions pg. 78
 COMPLETE SENTENCES