Section 22.3 Summary – pages 588

Unit 1: What is Biology?
Unit 2: Ecology
Unit 3: The Life of a Cell
Unit 4: Genetics
Unit 5: Change Through Time
Unit 6: Viruses, Bacteria, Protists, and Fungi
Unit 7: Plants
Unit 8: Invertebrates
Unit 9: Vertebrates
Unit 10: The Human Body
Unit 1: What is Biology?
Chapter 1: Biology: The Study of Life
Unit 2: Ecology
Chapter 2: Principles of Ecology
Chapter 3: Communities and Biomes
Chapter 4: Population Biology
Chapter 5: Biological Diversity and Conservation
Unit 3: The Life of a Cell
Chapter 6: The Chemistry of Life
Chapter 7: A View of the Cell
Chapter 8: Cellular Transport and the Cell Cycle
Chapter 9: Energy in a Cell
Unit 4: Genetics
Chapter 10: Mendel and Meiosis
Chapter 11: DNA and Genes
Chapter 12: Patterns of Heredity and Human Genetics
Chapter 13: Genetic Technology
Unit 5: Change Through Time
Chapter 14: The History of Life
Chapter 15: The Theory of Evolution
Chapter 16: Primate Evolution
Chapter 17: Organizing Life’s Diversity
Unit 6: Viruses, Bacteria, Protists, and Fungi
Chapter 18: Viruses and Bacteria
Chapter 19: Protists
Chapter 20: Fungi
Unit 7: Plants
Chapter 21:
Chapter 22:
Chapter 23:
Chapter 24:
What Is a Plant?
The Diversity of Plants
Plant Structure and Function
Reproduction in Plants
Unit 8: Invertebrates
Chapter 25: What Is an Animal?
Chapter 26: Sponges, Cnidarians, Flatworms, and
Chapter 27: Mollusks and Segmented Worms
Chapter 28: Arthropods
Chapter 29: Echinoderms and Invertebrate
Unit 9: Vertebrates
Chapter 30: Fishes and Amphibians
Chapter 31: Reptiles and Birds
Chapter 32: Mammals
Chapter 33: Animal Behavior
Unit 10: The Human Body
Chapter 34: Protection, Support, and Locomotion
Chapter 35: The Digestive and Endocrine Systems
Chapter 36: The Nervous System
Chapter 37: Respiration, Circulation, and Excretion
Chapter 38: Reproduction and Development
Chapter 39: Immunity from Disease
What Is a Plant?
The Diversity of Plants
Plant Structure and Function
Reproduction in Plants
Chapter 22 The Diversity of Plants
22.1: Nonvascular Plants
22.1: Section Check
22.2: Non-Seed Vascular Plants
22.2: Section Check
22.3: Seed Plants
22.3: Section Check
Chapter 22 Summary
Chapter 22 Assessment
What You’ll Learn
You will identify the characteristics of
the major plant groups.
What You’ll Learn
You will identify and compare the
distinguishing features of vascular and
nonvascular plants.
You will analyze the advantages of
seed production.
Section Objectives:
• Identify the structures of nonvascular plants.
• Compare and contrast characteristics of the
different groups of nonvascular plant.
What is a nonvascular plant?
• Because a steady
supply of water is
not available
nonvascular plants
are limited to moist
habitats by streams
and rivers or in
temperate and
tropical rain forests.
What is a nonvascular plant?
• Recall that a lack of
vascular tissue also
limits the size of a
• Nonvascular plants,
such as moss are
successful in
habitats with
adequate water.
Alternation of generations
• As in all plants, the life cycle of nonvascular
plants includes an alternation of generations
between a diploid sporophyte and a haploid
• However, nonvascular plant divisions
include the only plants that have a dominant
gametophyte generation.
Alternation of generations
• Sporophytes grow attached to and depend on
gametophytes to take in water and other
• Nonphotosynthetic
depend on their
for food.
Alternation of generations
• Gametophytes of nonvascular plants produce
two kinds of sexual reproductive structures.
• The antheridium is the male reproductive
structure in which sperm are produced.
Alternation of generations
• The archegonium is the female reproductive
structure in which eggs are produced.
• Fertilization, which begins the sporophyte
generation, occurs in the archegonium.
Adaptations in Bryophyta
• There are several divisions of nonvascular
• The first division you’ll study are the mosses,
or bryophytes.
• Mosses are small plants with leafy stems.
Adaptations in Bryophyta
• The leaves of
mosses are usually
one cell thick.
• Mosses have
rhizoids, colorless
structures, which
help anchor the
stem to the soil.
Adaptations in Bryophyta
• Some species have a
few, long waterconducting cells in
their stems.
• Mosses usually grow
in dense carpets of
hundreds of plants.
Adaptations in Bryophyta
• Some have upright stems; others have
creeping stems that hang from steep banks
or tree branches.
• Some mosses form extensive mats that help
retard erosion on exposed rocky slopes.
• Moses grow in a wide variety of habitats.
Adaptations in Bryophyta
• They even grow in the arctic during the brief
growing season where sufficient moisture is
• A well-known moss is Sphagnum, also
known as peat moss.
Adaptations in Bryophyta
• This plant thrives in acidic bogs in northern
regions of the world.
• It is harvested for use as fuel and is a
commonly used soil additive.
Adaptations in Hepaticophyta
• Another division of
nonvascular plants is the
liverworts, or
• Liverworts are small plants that usually grow
in clumps or masses in moist habitats.
Adaptations in Hepaticophyta
• The flattened body of a liverwort
gametophyte is thought to resemble the
shape of the lobes of an animal’s liver.
• A liverwort can be categorized as either
thallose or leafy.
Adaptations in Hepaticophyta
• The body of a thallose liverwort is called
a thallus. It is broad and ribbonlike and
resembles a fleshy, lobed leaf.
• Thallose liverworts are usually found
growing on damp soil.
Adaptations in Hepaticophyta
• Leafy liverworts grow close to the ground
and usually are common in tropical jungles
and areas with persistent fog.
• Their stems have flat, thin leaves arranged in
three rows—a row along each side of the stem
and a row of smaller leaves on the stem’s
lower surface.
• Liverworts have rhizoids that are
composed of only one elongated cell.
Adaptations in Anthocerophyta
• Anthocerophytes are the smallest division
of nonvascular plants, currently consisting
of only about 100 species.
• Also known as hornworts, these
nonvascular plants are similar to
liverworts in several respects.
Adaptations in Anthocerophyta
• Hornworts have
a thallose body.
• The
of a
the horn of
an animal.
Sporophyte with
sporangium (2n)
Gametophyte (n)
Adaptations in Anthocerophyta
• Another feature unique to hornworts is the
presence of one to several chloroplasts in
each cell of the sporophyte depending upon
the species.
• Unlike other nonvascular plants, the
hornwort sporophyte, not the gametophyte,
produces most of the food used by both
Origins of Nonvascular Plants
• Fossil and genetic evidence suggests that
liverworts were the first land plants.
• Fossils that have been positively
identified as nonvascular plants first
appear in rocks from the early Paleozoic
Era, more than 440 million years ago.
Origins of Nonvascular Plants
• Paleobotanists suspect that nonvascular
plants were present earlier than current
fossil evidence suggests.
• Both nonvascular and vascular plants
probably share a common ancestor.
Question 1
The only plants that have a dominant
gametophyte generation are the _______.
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
A. vascular plants
B. flowering plants
C. nonvascular plants
D. ferns
The answer is C.
Question 2
The rhizoid in mosses has a function
comparable to _______.
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
A. The flower in flowering plants
B. The cone in conifers
C. The root in vascular plants
D. The leaf in cycads
The answer is C. Rhizoids anchor the stems of
mosses to the soil as roots do in other plants.
Question 3
What is the main functional difference between
hornwort sporophytes and those of other
nonvascular plants?
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
Hornwort sporophytes contain chloroplasts
and produce most of the food for both
generations of the plant.
Section Objectives:
• Evaluate the significance of plant vascular
tissue to life on land.
• Identify and analyze the characteristics of
the non-seed vascular plant divisions.
What is a non-seed vascular plant?
• The obvious difference between a vascular
and a nonvascular plant is the presence of
vascular tissue.
• Vascular tissue is made up of tubelike,
elongated cells through which water and
sugars are transported.
• Vascular plants are able to adapt to changes
in the availability of water, and thus are
found in a variety of habitats.
What is a non-seed vascular plant?
Cambium produces xylem and
phloem as the plant grows.
Xylem transports
water and dissolved
substances other than
sugar throughout the
the plant.
Alternation of generations
• Vascular plants, like all plants, exhibit an
alternation of generations.
Alternation of generations
Sporophyte (2n)
Gametophyte (n)
• Unlike
plants, the sporeproducing vascular
sporophyte is
dominant and
larger in size than
the gametophyte.
Alternation of generations
Sporophyte (2n)
Gametophyte (n)
• The mature
does not
depend on the
for water or
Alternation of generations
• A major advance in this group of vascular
plants was the adaptation of leaves to form
structures that protect the developing
reproductive cells.
• In some non-seed vascular plants,
sporebearing leaves form a compact cluster
called a strobilus.
Alternation of generations
• A fern gametophyte is called a prothallus.
• Gametophytes are relatively small and live in
or on the soil.
• Antheridia and archegonia develop on the
• Sperm are released from antheridia and
require a continuous film of water to reach
eggs in the archegonia.
• Lycophytes are
commonly called
club mosses and
spike mosses.
Adaptations in Lycophyta
• Their leafy stems resemble moss
gametophytes, and their reproductive
structures are club or spike shaped.
• However, unlike mosses, the sporophyte
generation of the lycophytes is dominant.
Adaptations in Lycophyta
• It has roots, stems, and small leaflike
• A single vein of vascular tissue runs through
each leaflike structure.
• The stems of lycophytes may be upright or
creeping and have roots growing from the
base of the stem.
• The club moss,
Lycopodium, is
commonly called
ground pine because
it is evergreen and
resembles a
miniature pine tree.
Adaptations in Lycophyta
• Some species of ground pine have been
collected for decorative uses in such numbers
that the plants have become endangered.
• Arthrophytes, or
horsetails, represent
a second group of
ancient vascular
Adaptations in Arthrophyta
• Early horsetails were tree-sized members
of the forest community. Today’s
arthrophytes are much smaller than their
• There are only about 15 species in existence,
all of the genus Equisetum.
Adaptations in Arthrophyta
• The name horsetail
refers to the bushy
appearance of some
• These plants also are
called scouring rushes
because they contain
silica, an abrasive
Adaptations in Arthrophyta
• Most horsetails are found in marshes, in
shallow ponds, on stream banks, and other
areas with damp soil.
• The stem structure of horsetails is ribbed
and hollow, and appears jointed.
• At each joint, there is a whorl of tiny,
scalelike leaves.
Adaptations in Arthrophyta
• Arthrophyte spores are produced in strobili
that form at the tips of non-photosynthetic
• After the spores are released, they can grow
into gametophytes with antheridia and
Adaptations in Pterophyta
• According to fossil records, ferns—division
Pterophyta—first appeared nearly 375 million
years ago.
• Ancient ferns grew tall and treelike and
formed vast forests.
Adaptations in Pterophyta
Adaptations in Pterophyta
• Ferns range in size from a few meters tall,
like tree ferns, to small, floating plants that
are only a few centimeters in diameter.
Adaptations in Pterophyta
• Some ferns inhabit
dry areas,
becoming dormant
when moisture is
scarce and
resuming growth
and reproduction
only when water is
available again.
Fern Structures
• As with most vascular plants, it is the
sporophyte generation of the fern that has
roots, stems, and leaves.
• The part of the fern plant that we most
commonly recognize is the sporophyte
• The gametophyte in most ferns is a thin, flat
structure that is independent of the
Fern Structures
• In most
ferns, the
main stem is
This thick,
stem is called
a rhizome.
Fern Structures
• The leaves of a fern are called fronds and
grow upward from the rhizome.
• The fronds are often divided into leaflets
called pinnae, which are attached to a central
• The branched veins in ferns transport water
and food to and from all the cells.
Fern Structures
• Fern spores are produced in structures
called sporangia.
Fern Structures
• Clusters of
sporangia form a
structure called a
sorus (plural, sori).
Sori are usually
found on the
underside of fronds
but in some ferns,
spores are borne on
modified fronds.
Origins of Non-Seed Vascular Plants
• The earliest evidence of non-seed vascular
plants is found in fossils from early in the
Devonian Period, around 375 million years
• Many of these species of non-seed vascular
plants died out about 280 million years ago
—a time when Earth’s climate was cooler
and drier.
Origins of Non-Seed Vascular Plants
11 000 species
1150 species
15 species
100 species
6 species
20 000 species
6500 species
Species numbers are approximate and subject to change pending discoveries or extinctions.
Origins of Non-Seed Vascular Plants
• Today’s non-seed vascular plants are much
smaller and less widespread in their
distribution than their prehistoric ancestors.
• The evolution of vascular tissue enabled
these plants to live on land and to maintain
larger body sizes in comparison with
nonvascular plants.
Question 1
Using the figure,
which structure
would you
assume the
grows from?
(TX Obj 2; 8C,
10A, 10B
TX Obj 3; 13A)
The answer is the
Sperm travel from
the antheridium to
the archegonium
where they unite
with an egg and
form a zygote.
The zygote
grows into the
Question 2
A compact cluster of spore-bearing leaves is
called a _______.
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
A. thallus
C. prothallus
B. rhizoid
D. strobilus
The answer is D.
Question 3
The first plants to have evolved leaves with
branching veins of vascular tissue are the
_______. (TX Obj 2; 8C, 10A, 10B
TX Obj 3; 13A)
A. Pterophytes
B. Arthrophytes
The answer is A.
C. Lycophytes
D. Anthocerophytes
Question 4
The main stem of most ferns is called a _______.
TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
A. rachis
B. frond
C. sorus
D. rhizome
The answer is D.
Section Objectives:
• Identify and analyze the characteristics of
seed plants.
• Analyze the advantages of seed and fruit
What is a seed plant?
• Some vascular plants produce seeds in which
reduced sporophyte plants are enclosed within
a protective coat.
Seed plants produce spores
• In seed plants, as in all other plants, spores
are produced by the sporophyte generation.
• These spores develop into the male and
female gametophytes.
Seed plants produce spores
• The male gametophyte develops inside a
structure called a pollen grain that includes
sperm cells, nutrients, and a protective outer
Seed plants produce spores
• The female gametophyte, which produces the
egg cell, is contained within a sporophyte
structure called an ovule.
Fertilization and reproduction
• The union of the sperm and egg, called
fertilization, forms the sporophyte zygote.
• Because they do not require a continuous
film of water for fertilization, seed plants
are able to grow and reproduce in a wide
variety of habitats that have limited water
Fertilization and reproduction
• After fertilization, the zygote develops into
an embryo. An embryo is an early stage of
development of an organism.
• Embryos of seed plants include one or more
Fertilization and reproduction
• Cotyledons
usually store
or absorb
food for the
Seed coat
Advantages of seeds
• A seed consists of an
embryo and its food
supply enclosed in a
tough, protective coat.
• The seed contains a
supply of food to
nourish the young
plant during the early
stages of growth.
Advantages of seeds
• In conifers and some flowering plants, the
embryo’s food supply is stored in the
• The embryo is protected during harsh
conditions by a tough seed coat.
• The seeds of many species are also adapted
for easy dispersal to new areas.
Diversity of seed plants
• In some plants,
seeds develop on the
scales of woody
strobili called cones.
Diversity of seed plants
• This group of plants is sometimes referred
to as gymnosperms.
• The gymnosperm plant divisions you will
learn about are Cycadophyta, Ginkgophyta,
Gnetophyta, and Coniferophyta.
Diversity of seed plants
• Flowering plants,
also called
produce seeds
enclosed within
a fruit. A fruit
includes the
ripened ovary of
a flower.
Diversity of seed plants
• The fruit provides
protection for seeds
and aids in seed
• The Anthophyta
division contains all
species of flowering
Adaptations in Cycadophyta
• Cycads have male and female reproductive
systems on separate plants.
Adaptations in Cycdophyta
• The male system includes cones that produce
pollen grains, which produce motile sperm.
• Cycads are one of the few seed plants that
produce motile sperm.
• The female system includes cones that
produce ovules.
Adaptations in Ginkgophyta
• All ginkgoes are cultivated trees, and they are
not known to exist in the wild.
Adaptations in Ginkgophyta
• Like cycads, gingko male and female
reproductive systems are on separate plants.
• The male ginkgo produces pollen grains in
strobiluslike cones that grow from the bases
of leaf clusters.
• Ginkgo pollen grains produce motile sperm.
Adaptations in Ginkgophyta
• The female ginkgo produces ovules which,
when fertilized, develop fleshy, apricotcolored seed coats.
• These soft seed coats give off a foul odor when
broken or crushed.
• Ginkgoes often are planted in urban areas
because they tolerate smog and pollution.
Adaptations in Ginkgophyta
• The division Gnetophyta contains only three
genera, which have different structural
adaptations to their environments.
• The genus Gnetum is composed of tropical
climbing plants.
• The genus Ephedra contains shrublike
plants and is the only gnetophyte genus
found in the United States.
Adaptations in Gnetophyta
• The third genus, Welwitschia, is a bizarrelooking plant found only in South Africa. It
grows close to the ground, has a large
tuberous root, and may live 1000 years.
Adaptations in Coniferophyta
• The conifers
are trees and
shrubs with
needlelike or
Adaptations in Coniferophyta
• They are abundant
in forests throughout
the world, and
include pine, fir,
spruce, juniper,
cedar, redwood,
yew, and larch.
Adaptations in Coniferophyta
• The reproductive structures of most conifers
are produced in cones.
Pollen grain
Two seeds
Adaptations in Coniferophyta
• Most conifers have male and female cones on
different branches of the same tree.
• The male cones produce pollen.
• Female cones are much larger. They stay
on the tree until the seeds have matured.
Pine Needles
• The needles of pines have several adaptations
that enable the plants to conserve water during
the cold dry winter and the dry heat of the
Cross section of
needle bundle
Modified leaf cells
Papery sheath
Bundles of needles
Recessed stomata
Evergreen conifers
• Most conifers are evergreen plants—plants that
retain some of their leaves for more than one
Evergreen conifers
• Plants that retain some of their leaves yearround can photosynthesize whenever favorable
environmental conditions exist. This is an
advantage in environments where the growing
season is short.
Evergreen conifers
• Another advantage of leaf retention is that a
plant’s food reserves are not depleted each
spring to produce a whole set of new leaves.
• Evergreen leaves usually have a heavy coating
of cutin, a water-insoluble, waxy material that
helps reduce water loss.
Deciduous trees lose their leaves
• A few conifers, including larches and bald
cypress trees, are deciduous.
• Deciduous plants drop all their leaves each
fall or when water is scarce or unavailable
as in the tundra or in deserts.
Deciduous trees lose their leaves
• Dropping all leaves is an adaptation for
reducing water loss. However, a tree with no
leaves cannot photosynthesize and must
remain dormant during this time.
Adaptations in
• Flowering plants are
classified in the
division Anthophyta.
Adaptations in Anthophyta
• Like other seed plants, anthophytes have
roots, stems, and leaves. But unlike the other
seed plants, anthophytes produce flowers and
form seeds enclosed in a fruit.
Fruit production
• Anthophyta is unique among plant divisions.
It is the only division in which plants have
flowers and produce fruits.
• A fruit develops from a flower’s female
reproductive structure(s).
Fruit production
• A fruit usually
contains one or more
• One of the
advantages of fruitenclosed seeds is the
added protection the
fruit provides for the
young embryo.
Seed coat
Fruit production
• Seeds of some species that are eaten pass
through the animal’s digestive tract
unharmed and are distributed as the animal
wanders. In fact, some seeds must pass
through a digestive tract before they can
begin to grow a new plant.
Fruit production
• Some fruits have structural adaptations that
help disperse the seed by wind or water.
Moncots and dicots
• The division Anthophyta is divided into two
classes: monocotyledons and dicotyledons.
• Monocotyledons have one seed leaf;
dicotyledons have two seed leaves.
Moncots and dicots
Distinguishing Characteristics of Monocots and Dicots
Seed Leaves
Vascular Bundles Vascular Bundles Flower Parts
in Stems
in Leaves
One cotyledon
Usually parallel
Multiples of
Usually netlike
Arranged in ring
Multiples of
four and five
Moncots and dicots
• Moncots
orchids, lilies,
and palms.
Moncots and dicots
• Dicot species
include nearly all
of the familiar
shrubs and trees
(except conifers),
cacti, wildflowers,
garden flowers,
vegetables, and
Life spans of anthophytes
• The life span of a plant is genetically
determined and reflects strategies for
surviving periods of harsh conditions.
Life spans of anthophytes
• Annual plants live
for only a year or
less. They sprout
from seeds, grow,
reproduce, and die
in a single growing
Life spans of
• Annuals form
seeds that survive
the winter.
Life spans of anthophytes
• Biennial plants have life spans that last two
Life spans of anthophytes
• Many biennials
develop large storage
roots, such as carrots,
beets, and turnips.
• During the first
year, biennials
grow many leaves
and develop a
strong root system.
Life spans of anthophytes
• Over the winter, the aboveground portion
of the plant dies back, but the roots
remain alive.
• During the second spring, food stored in
the root is used to produce new shoots that
produce flowers and seeds.
Life spans of anthophytes
• Perennials live for several years, producing
flowers and seeds periodically—usually once
each year.
Life spans of anthophytes
• They survive harsh conditions by
dropping their leaves or dying back to
soil level, while their woody stems or
underground storage organs remain
intact and dormant.
Origin of Seed Plants
• Seed plants first appeared about 360 million
years ago during the Paleozoic Era.
• Some seed plants, such as ancient relatives of
cycads and ginkgoes, shared Earth’s forest with
the dinosaurs during the Mesozoic Era.
• About 65 million years ago, most members of
the Ginkgophyta died out along with many
organisms during a mass extinction.
Origin of Seed Plants
• According to fossil evidence, the first conifers
emerged around 250 million years ago.
• Anthophytes first appeared about 140 million
years ago late in the Jurassic Period of the
Mesozoic Era.
Origin of Seed Plants
1 species
250 000 species
65 species
600 species
200 species
Species numbers are approximate and subject to change pending discoveries or extinctions.
Question 1
A pollen grain contains a _______.
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
A. seed
B. embryo
C. gametophyte
D. sporophyte
The answer is C.
Question 2
Why are seeds adapted for easy dispersal to
new areas an advantage for plants?
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
When the seeds germinate in new areas, the
new plants do not have to compete with the
parent plant for sunlight, water, soil
nutrients, and living space.
Question 3
The strobilus in some non-seed vascular plants
is comparable to what in gymnosperms?
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
A. seed
B. cone
C. pollen grain
D. ovule
The answer is B.
Nonvascular Plants
• Nonvascular plants lack vascular tissue and
reproduce by producing spores. The
gametophyte generation is dominant.
• There are three divisions of nonvascular
plants: Bryophyta, Hepaticophyta, and
Non-seed Vascular Plants
• The non-seed vascular plants were predominant
in Earth’s ancient forests. They are represented
by modern species.
• Vascular tissues provide the structural support
that enables vascular plants to grow taller than
nonvascular plants.
• There are three divisions of non-seed vascular
plants: Lycophyta, Arthrophyta, and
Seed Plants
• Seeds contain a supply of food to nourish the
young plant, protect the embryo during harsh
conditions, and provide methods of dispersal.
• There are four divisions of vascular plants
that produce naked seeds: Cycadophyta,
Gnetophyta, Ginkgophyta, and
Seed Plants
• Anthophytes produce flowers and have
seeds enclosed in a fruit.
• Fruits provide protection for the seeds
and aid in their dispersal.
Seed Plants
• Anthophytes are either monocots or dicots
based on the number of cotyledons present in
the seed.
• Anthophytes may be annuals, biennials, or
Question 1
Cycadophytes and Ginkgophytes have the
following in common except _______.
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
A. Both divisions have male and female
reproductive systems on separate plants.
B. Both divisions produce motile sperm.
Question 1
Cycadophytes and Ginkgophytes have the
following in common except _______.
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
C. Both divisions have only one species
growing wild in the United States.
D. Both divisions produce pollen grains in
The answer is C. Ginkgophytes are not known
to exist in the wild. They are cultivated plants.
Question 2
Which of the following is not an advantage for
evergreen conifers?
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
A. They can photosynthesize whenever
favorable environmental conditions exist.
B. Their food reserves are not depleted
each spring to produce a whole set of
new leaves.
Question 2
Which of the following is not an advantage for
evergreen conifers?
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
C. Their fruit protect their seeds against harsh
environmental conditions.
D. Their leaf shape helps reduce water loss.
The answer is C. Conifers have naked seeds
with no fruit.
Question 3
Why is winter an optimal time for deciduous
plants to have no leaves?
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A
Less water is available to plants in winter,
so they must reduce water loss, the most of
which is through leaves. Sunlight is reduced
as well, so leaves would not
photosynthesize as much in winter.
Question 4
Most wood used for building in the United States
comes from _______.
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
A. Anthophytes
B. Coniferophytes
C. Cycadophytes
D. Pterophytes
The answer is B.
Most wooden
materials come
from conifers.
Question 5
Most grain crops are _______.
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
A. annuals
B. biennials
C. perennials
D. dicots
The answer is A.
Question 6
Cactuses are examples of _______.
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
A. annual monocots
B. biennial dicots
C. perennial dicots
D. perennial monocots
The answer is C.
Question 7
Palms are examples of which of the following
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
A. Cycadophytes
B. Gnetophytes
C. deciduous monocots
D. perennial monocots
The answer is D.
Question 8
The gametophyte generation is dominant in
which of the following plants?
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
A. horsetails
B. club moss
C. sphagnum
D. bird’s nest ferns
The answer is C. The gametophyte generation is
dominant in sphagnum moss.
Question 9
Which of the following pairs are not related?
(TX Obj 2; 8C, 10A, 10B, TX Obj 3; 13A)
A. sorus – sporangia
B. hornworts – rhizomes
C. ovaries – fruits
D. pollen – gametophytes
The answer is B.
Question 10
What is the method of dispersal of seeds covered
in burrs? (Tx Obj 2; 8c, 10a, 10b, 13b)
A. water
B. wind
C. animals
D. insects
The answer is C. Seeds covered in burrs are
dispersed by clinging to the skin and fur of
Photo Credits
• Digital Stock
• Carolina Biological Supply Co.
• Geoff Butler
• David M. Dennis
• Matt Meadows
• PhotoDisc
• Marty Pardo
• Amanita Pictures
• Studiohio
• Alton Biggs
To advance to the next item or next page click on any of the
following keys: mouse, space bar, enter, down or forward
Click on this icon to return to the table of contents
Click on this icon to return to the previous slide
Click on this icon to move to the next slide
Click on this icon to open the resources file.
End of Chapter 22 Show