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Unit Projects

Unit ProjectsUnit ProjectsUnit Projects

Unit 7Unit 7Advance PlanningChapter 21■ Purchase mustard seeds for the

Alternative Lab.■ Order Marchantia for MiniLab

21-1 and Lycopodium for Mini-Lab 21-2.

Chapter 22■ Collect seeds and fruits for the

Getting Started Demo.■ Order or collect fern sporangia

for MiniLab 22-1 and seedsfor MiniLab 22-2.

Chapter 23■ Leave some broadleaf house-

plants near a sunny window toelicit a phototropic responsefor the Quick Demo.

Chapter 24None

ExperimentingLogical-Mathematical Have stu-dents design and perform an exper-

iment to test one aspect of plant growth.L2

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InterviewingLinguistic Have students interviewa florist or nursery worker to learn

how they keep flowers and plants freshand healthy. L1

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Final ReportHave student groups present their find-ings about plants in reports that could bepresented to students at your local mid-dle schools.

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PlantsPlantsPlants, large and small, are found allover Earth—from the frozen arctic circle to harsh desert environments andlush tropical rain forests. There are characteristics shared by all plants, as wellas unique features of individual species.The great beauty and diversity of plants is a source of endless wonder. In additionto their great beauty and diversity, plantsprovide us with food and oxygen. Life onEarth would not be possible without theseamazing organisms. In this unit you willexplore the fascinating world of plants.

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UNIT CONTENTSUNIT CONTENTS

What is a Plant?

Diversity of Plants

Plant Structure and Function

Reproduction in Plants

UNIT PROJECTUNIT PROJECT

Use the Glencoe Science Web Site for more project

activities that are connected to this unit.www.glencoe.com/sec/science

Unit 7Unit 7

PlantsBIODIGESTBIODIGEST

Unit ProjectsUnit ProjectsUnit Projects

Unit Projects

Unit 7Unit 7

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Plants

Unit OverviewUnit 7 introduces the plant king-dom. The unit begins in Chapter21 with a brief discussion of plantorigins and the adaptations ofplants to life on land. This chap-ter also introduces the 12 plantdivisions.

In Chapter 22, students learnthe major characteristics of eachplant division. Students learnabout plant cells and tissues inChapter 23. This chapter alsodescribes root, stem, and leafanatomy and plants’ responses tothe environment.

The unit concludes in Chapter24 where reproduction in plantsis examined.

Introducing the UnitThe majestic Sequoia suggests theimportance of plants to life onEarth. These trees are the largestliving plants on Earth. Use thisphotograph to initiate a class dis-cussion on plants as living organ-isms and the vital role plants playin the ecosystem.

Exploring the World ofPlantsHave students do one of the projects forthis unit as described on the GlencoeScience Web Site. As an alternative, stu-dents can do one of the projects describedon these two pages.

DisplayVisual-Spatial Students can collectexamples of different plants from

magazines. They should make a displaythat illustrates the wide variety of plantspecies.

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ModelingKinesthetic Have groups of stu-dents design and create a model of

a typical flowering plant. They may useany available materials.

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Refer to pages 4T-5T of the Teacher Guide for an explanation of the National Science Education Standards correlations. Teacher Classroom Resources

Assessment Resources Additional Resources

Products Available FromGlencoeTo order the following products,call Glencoe at 1-800-334-7344:CD-ROMNGS PictureShow: What ItMeans to Be GreenCurriculum KitGeoKit: PlantsTransparency SetNGS PicturePack: What It Meansto Be GreenVideodiscSTV: Plants

Index to NationalGeographic MagazineThe following articles may beused for research relating to thischapter:“Saving the World’s LargestPower,” by Willem Meijer, July1985.“The Poppy,” by Peter T. White,February 1985.“Stalking the West’s WildFoods,” by Euell Gibbons,August 1973.“Stalking Wild Foods on aDesert Isle,” by Euell Gibbons,July 1972.“Plants That Eat Insects,” byPaul A. Zahl, May 1961.

Teacher’s Corner

574B

What Is a Plant?What Is a Plant?

TransparenciesReproducible MastersSection

Adapting to Life on Land

Survey of thePlant Kingdom

Section 21.1

Section 21.2

Teacher Classroom Resources

Reinforcement and Study Guide, pp. 93-94Concept Mapping, p. 21Critical Thinking/Problem Solving, p. 21BioLab and MiniLab Worksheets, p. 97Laboratory Manual, pp. 145-152Content Mastery, p. 105-106, 108

Reinforcement and Study Guide, pp. 95-96Critical Thinking/Problem Solving, p. 21BioLab and MiniLab Worksheets, pp. 98-100Content Mastery, p. 105, 107-108 L1

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Section Focus Transparency 50

Section Focus Transparency 51Basic Concepts Transparency 33

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LSAssessment Resources Additional Resources

Spanish ResourcesEnglish/Spanish AudiocassettesCooperative Learning in the Science ClassroomLesson Plans/Block Scheduling

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Chapter Assessment, pp. 121-126MindJogger VideoquizzesPerformance Assessment in the Biology ClassroomAlternate Assessment in the Science ClassroomComputer Test BankBDOL Interactive CD-ROM, Chapter 21 quiz

Chapter 21 OrganizerChapter 21 Organizer

Activities/FeaturesObjectivesSection

Adapting to Life on LandNational Science EducationStandards UCP.1-5; B.2; C.5,C.6; E.1, E.2; F.3, F.4, F.6;G.1-3 (1 session, 1 block)

Survey of the Plant KingdomNational Science EducationStandards UCP.1, UCP.3,UCP.4, UCP.5; A.1, A.2; C.4,C.5, C.6; E.2; F.1, F.3, F.6;G.1-3 (2 sessions, 1 block)

1. Compare and contrast characteristicsof algae and plants.

2. List the characteristics of plants thatadapt them for life on land.

3. Describe the alternation of generationin land plants.

4. Describe the phylogenic relationshipsamong divisions of plants.

5. Identify the twelve plant kingdom divisions.

MiniLab 21-1: Examining Land Plants p. 577Problem-Solving Lab 21-1, p. 579Focus On Plants for People, p. 580

MiniLab 21-2: Looking at Modern and FossilPlants, p. 586Problem-Solving Lab 21-2, p. 588Internet BioLab: Researching Trees on theInternet, p. 590Health Connection: Medicine from Plants,p. 592

Section 21.2

Section 21.1

MATERIALS LIST

BioLabp. 590 Internet access

MiniLabsp. 577 live or preserved sample ofMarchanita, stereomicroscopep. 586 live or preserved samples ofLycopodium and Equisetum

Alternative Labp. 576 petri dish, black paper, scissors,microscope, hand lens, microscopeslide, coverslip, water, forceps, mustardseeds, label

Quick Demosp. 576 pictures of land plants andgreen algaep. 585 pine needles, broad-leaves

Need Materials? Contact Carolina Biological Supply Company at 1-800-334-5551or at http://www.carolina.com

574A

Key to Teaching StrategiesKey to Teaching Strategies

Level 1 activities should be appropriatefor students with learning difficulties.Level 2 activities should be within theability range of all students.Level 3 activities are designed for above-average students.ELL activities should be within the abilityrange of English Language Learners.

Cooperative Learning activitiesare designed for small group work.These strategies represent student prod-ucts that can be placed into a best-workportfolio.These strategies are useful in a blockscheduling format.

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The following multimedia resources are available from Glencoe.

Biology: The Dynamics of LifeCD-ROM

BioQuest: Biodiversity ParkVideo: Giant Redwoods

The Infinite VoyageA Taste of HealthTo the Edge of the Earth

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Origins of Plants What is a plant? A plant is a multi-

cellular eukaryote that can produce itsown food in the form of glucosethrough the process of photosynthe-sis. In addition, plant cells are charac-terized by having thick cell walls madeof cellulose. The stems and leaves ofplants have a waxy waterproof coat-ing called a cuticle (KYEWT ih kul).

Fossils and other geological evi-dence suggest that a billion years ago,plants had not yet begun to appearon land. No ferns, mosses, trees,grasses, or wildflowers existed. Theland was barren except for somealgae at the edges of inland seas and

oceans. However, the shallow watersthat covered much of Earth’s surfaceat that time were teeming with bacte-ria, algae, and other protists, as wellas simple animals such as corals,sponges, jellyfishes, and worms.Among these organisms were greenalgae that would eventually becomeadapted to life on land.

The first evidence of plants in thefossil record began to appear around500 million years ago. These earlyplants were very simple in structureand did not have any leaves. Theywere probably instrumental in turn-ing bare rock into rich soil. The earl-iest known plant fossils are those ofplants called psilophytes (SI luh fites),

21.1 ADAPTING TO LIFE ON LAND 575

When you studied ecology, youlearned that plants are importantin defining biomes, ecosystems,

and communities. A desert biome may seemtoo hot and dry for living plants, but theSaguaro cactus and many other plants flourish there. Mosses are plants that would never survive the desert.Instead, they are found in cool,damp areas. Although cacti and mosses are very different, they share characteristics common to all plants.

SECTION PREVIEW

ObjectivesCompare and contrast characteristicsof algae and plants.List the characteristicsof plants that adaptthem for life on land.Describe the alterna-tion of generation inland plants.

Vocabularycuticleleafrootstemvascular tissuevascular plantnonvascular plantseed

21.1 Adapting to Life on Land

OriginWORDWORD

cuticle From the Greekword cutis, meaning“skin.” The cuticleis the outermostcovering of a plant.

A Saguaro cactusand mosses (inset)

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Section 21.1

BIOLOGY: The Dynamics of Life SECTION FOCUS TRANSPARENCIES

Use with Chapter 21,Section 21.1

How would you describe the environment in whichthese plants live?

What are some adaptations that help plants live in thistype of environment?

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PrepareKey ConceptsEvidence for land plants evolvingfrom algae and the adaptationsneeded for land survival are cov-ered. An overview of leaf, stem,and root anatomy is presented inconjunction with the adaptationsof plants that allow them to liveon land.

Planning■ Collect plants for the Getting

Started Demo.■ Collect pictures of plants and

algae for the Quick Demo.■ Purchase mustard seeds for the

Alternative Lab.■ Collect leaf specimens for the

Meeting Individual Needs.■ Purchase bean seeds for the

Project.

1 FocusBellringer Before presenting the lesson, display Section Focus Trans-parency 50 on the overhead pro-jector and have students answerthe accompanying questions.

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Assessment PlannerAssessment PlannerPortfolio Assessment

Assessment, TWE, p. 576Portfolios, TWE, pp. 580, 585

Performance AssessmentMiniLab, SE, p. 577Alternative Lab, TWE, p. 577Problem-Solving Lab, TWE, p. 578BioLab, SE, p. 591

Knowledge AssessmentAlternative Lab, TWE, p. 577

Assessments, TWE, pp. 579, 585, 589MiniLab, TWE, p. 586Problem-Solving Lab, p. 588Section Assessments, SE, pp. 579, 589Chapter Assessment, SE, pp. 593-596

Skill AssessmentMiniLab, TWE, p. 577BioLab, SE, p. 591

574 WHAT IS A PLANT?

What Is a Plant?

What You’ll Learn■ You will identify the adapta-

tions that enable plants tolive on land.

■ You will distinguish amongthe major divisions of plants.

Why It’s ImportantPlants were the first multicellu-lar organisms to colonize landalmost 500 million years ago.Since then, plants have devel-oped into an incredibly diversegroup of organisms that helpprovide us with food, oxygen,and shelter.

Discovering PlantsUse a variety of real plants orphotos from books and maga-zines to compare a number ofdifferent plants. How are theysimilar? How do they differ?

To find outmore about

plants, visit the Glencoe ScienceWeb Site.www.glencoe.com/sec/science

21

GETTING STARTEDGETTING STARTED

ChapterChapter

Plants provide examples ofdiversity within a kingdom.The banks of a pond may becovered by beautiful flow-ers, which you can easilysee, and small mosses andliverworts, which are lessprominent. The plant inthe inset photo is a gera-nium, a common floweringplant found in houses andhanging baskets.

574

Theme DevelopmentThe theme of unity withindiversity is well illustrated in thischapter. Differences amongplants in various divisions are dis-cussed, and their similarity inreproduction via alternation ofgenerations is stressed. TheEvolution of plants is also amajor theme in the discussion ofthe evolution of land plants fromgreen algae.

Chapter 21Chapter 21

MultipleLearningStyles

Look for the following logos for strategies that emphasize different learning modalities.

Kinesthetic Meeting IndividualNeeds, p. 578; Activity, p. 583Linguistic Portfolio, p. 580

Visual-Spatial Getting StartedDemo, p. 574; Quick Demos,

pp. 576, 585; Portfolios, pp. 578, 585;Extension, p. 579; Meeting Individual

Needs, pp. 580, 587; Visual Learning,p. 581; Biology Journal, p. 585;Display, p. 587; Reteach, p. 589

Logical-MathematicalDiscussion, p. 579Intrapersonal Enrichment, p. 581

GETTING STARTED DEMOGETTING STARTED DEMO

Visual-Spatial Have stu-dents examine a variety of

houseplants and list their distin-guishing characteristics. Appro-priate plants include cacti, othersucculents, ivies, and broad-leaved plants such as philoden-drons and begonias.

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If time does not permit teach-ing the entire chapter, use theBioDigest at the end of theunit as an overview.

Resource ManagerResource Manager

Section Focus Transparency 50and Master

Concept Mapping, p. 21

Critical Thinking/ProblemSolving, p. 21

Tech Prep Applications, pp. 31-32 L2

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Leaves carry out photosynthesisAll the cells of a filamentous green

alga carry out photosynthesis. But inmost land plants, the leaves are theorgans usually responsible for photo-synthesis. A leaf is a broad, flat struc-ture of a plant that traps light energyfor photosynthesis, Figure 21.2.They are supported by the stem andgrow upward toward sunlight.

Putting down rootsMost plants depend on the soil as

their primary source for water andother nutrients. Plants are able toacquire water and nutrients from thesoil with their roots. In most plants, aroot is a plant organ that absorbswater and minerals from the soil,transports those nutrients to thestem, and anchors the plant in theground. Some roots, such as those ofradishes or sweet potatoes, also accum-ulate starch reserves and function asorgans of storage. Many people usethese storage roots as a food source.Find out more about the many usesof plants in Focus On at the end ofthis section.

Practice your lab skills by using adissecting microscope in the MiniLabon this page to explore some of theadaptations of plants that allow themto survive on land.

Transporting materialsWater moves from the roots of a

tree to its leaves, and the sugars pro-duced in the leaves move to the rootsthrough the stem. A stem of a plantprovides structural support forupright growth and contains tissuesfor transporting food, water, andother materials from one part of the plant to another, as shown in Figure 21.3. Stems may also serve asorgans for food storage. Green stemscontain chlorophyll and take part inphotosynthesis.

Examining Land Plants Liverwortsare considered to be one of the sim-plest of all land plants. They showmany of the adaptations that otherland plants have evolved thatenable them to survive on a landenvironment.

Procedure! Examine a living or preserved sample of

Marchantia. CAUTION: Wear disposablelatex gloves when handling preserved materials.

@ Note and record the following observations. Is the plantunicellular or multicellular? Does it have a top and bot-tom? How do these differ? Is it one cell in thickness ormany cells thick? Does the plant seem to grow uprightlike a tree or is it flat to the ground?

# Use a dissecting microscope to examine its top and bot-tom surfaces. Are tiny holes or pores present? If youanswer “yes,” which surface has pores?

Analysis1. How might having a multicellular, thick body be an

advantage to life on land?2. Are any structures present that resemble roots? How

might they help a land plant?3. How might its growth pattern help it survive land?4. What might be the role of any pores observed on the

plant? Why is the location of the pores critical to survivingon a land environment?

MiniLab 21-1MiniLab 21-1

Marchantia

Figure 21.3 Stems can be soft andflexible like the daisystem shown here (a).Other plants, such asthis sugar maple tree,have strong, thickstems that providesupport and allow the tree to grow to greatheights (b).

Applying Concepts

b

Purpose Students will correlate theirobservations of liverwort struc-tures with traits that aid in thesurvival of plants on land.

Process Skillsobserve and infer, think critically,apply concepts

Teaching Strategies■ Obtain preserved liverwortsfrom a biological supply house.Order plants without reproduc-tive structures if possible. ■ Hand lenses can be substitutedfor dissecting microscopes.■ Remind students that plantsmake their own food throughphotosynthesis. Review the needfor chlorophyll, carbon dioxide,and water in photosynthesis.Review the source of carbondioxide and water for land plants.

Expected ResultsStudents will examine a liverwortand correlate their observationson liverwort structure with adap-tations of land plants.

Analysis1. water can be retained in cells

that help the plant retainmoisture

2. yes; enables plant to obtainwater and minerals from soil,helps anchor plant to ground

3. growing close to ground mayreduce drying out from windand help the plant retainmoisture.

4. gas exchange—carbon dioxideand oxygen can enter plant;carbon dioxide and oxygenare present in air—upper sur-face is exposed to air

Skill Have students ob-serve and diagram a preparedslide of a cross section of March-antia. All structures described inthe MiniLab can be observed.Have students diagram what theysee and correlate how each struc-ture aids in the survival of thisland plant. Use the PerformanceTask Assessment List for Scien-tific Drawing in PASC, p. 55.

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Analysis1. How many days were needed for root

hairs to appear? two to three2. Estimate the number of root hairs that

were visible. Explain why this numberis adaptive. hundreds; increases areafor water absorption

3. Was a single root hair multicellular orunicellular? unicellular

Knowledge Have students give apresentation discussing the various func-tions of roots and how they help plantsto survive on land. Use the PerformanceTask List for Oral Presentation inPASC, p. 71. L2

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577

some of which still exist today, suchas those shown in Figure 21.1.

Scientists think that all plants prob-ably evolved from filamentous greenalgae that lived in the ancient oceans.Some of the evidence for their rela-tionship can be found in modernmembers of both groups. Both greenalgae and plants have cell walls thatcontain cellulose. Both groups havethe same types of chlorophyll used inphotosynthesis. Both algae and plantsstore food in the form of starch. Allother major groups of organismsstore food in the form of glycogenand other complex sugars.

Adaptations in PlantsLife on land has advantages as well

as challenges. All organisms needwater to survive. A filamentous greenalga floating in a pond does not needto conserve water. The alga is com-pletely immersed in a bath of waterand dissolved nutrients, which it canabsorb directly into its cells. Formost land plants, the only availablesupply of water and minerals is in thesoil, and only the portion of the plantthat penetrates the soil can absorbthese nutrients.

When you studied protists, youlearned that algae reproduce byreleasing unprotected unicellulargametes into the water, where fertil-ization and development take place.Land plants have evolved severaladaptations that help protect thegametes from drying out. In someplants, the sperm are released near theegg so they only have to travel a shortdistance. Other plants have protectivestructures to ensure the survival of thegametes. Land plants must also with-stand the forces of wind and weatherand be able to grow upright againstthe force of gravity. Over the past500 million years or so, plants havedeveloped a huge variety of adapta-tions that reflect both the challengesand advantages of living on land.

Preventing water lossIf you run your fingers over the

surface of an apple, a maple leaf, orthe stem of a houseplant, you’ll prob-ably find that it feels smooth andslightly slippery. Most fruits, leaves,and stems are covered with a protec-tive, waxy layer called the cuticle.Waxes and oils are lipids, and youhave previously read that lipids do notdissolve in water. The waxy cuticlecreates a barrier that helps preventthe water in the plant’s tissues fromevaporating into the atmosphere.

576 WHAT IS A PLANT?

Figure 21.1 This fossil ofCooksonia is morethan 400 millionyears old (a).Cooksonia was prob-ably one of the firstvascular plants. Theplant had leaflessstems (b).

Figure 21.2 Leaves take advan-tage of the plentifulsupply of sunlightand carbon dioxideavailable to landplants.

a

b

Portfolio Have studentsprepare an illustrated time linethat indicates when plants firstevolved onto land, and what earlyland plants might have lookedlike. Have students indicate howthe appearance of plants may havediffered 100 million years afterthey first became land organisms.

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AssessmentAssessment

Alternative LabRoot Hairs

Purpose This lab will allow students to examine thenumber and nature of root hairs.Materials Petri dish, black paper, scissors, microscope,

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hand lens, glass slide, coverslip, water, for-ceps, mustard seeds, labelProcedureGive the students the following directions.

1. Cut out several thicknessess of blackpaper to fit the inside bottom of apetri dish. Moisten the paper.

2. Add 10 mustard seeds to the dish andcover. Label your dish.

3. Examine the dish each day to look forevidence of germination. Record your

observations with daily diagrams.4. Use a hand lens to check for the

appearance of root hairs.5. After several days, use forceps to re-

move several root hairs. Prepare a wetmount of the hairs and examine themunder a microscope. Determine if roothairs are multicellular or unicellular.

Expected ResultsStudents will see hundreds of unicellularroot hairs.576

Quick DemoQuick Demo

Visual-Spatial Show stu-dents pictures of green

algae and land plants. Ask themto describe the different condi-tions under which each organ-ism exists.

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MiniLab 21-1MiniLab 21-1

Resource ManagerResource Manager

Reinforcement and StudyGuide, pp. 93-94

BioLab and MiniLabWorksheets, p. 97

Content Mastery, p. 106Laboratory Manual,

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2 Teach

The stems of most plants containvascular tissues. Vascular tissues(VAS kyuh lur) are made up of tubelike,elongated cells through which water,food, and other materials are trans-ported. Plants that possess vasculartissues are known as vascular plants.Most of the plants you are familiarwith, including pine and maple trees,ferns, rhododendrons, rye grasses,English ivy, and sunflowers, are vas-cular plants.

Mosses and several other small, less-familiar plants called hornworts andliverworts are usually classified as non-vascular plants. Nonvascular plantsdo not have vascular tissues. The tis-sues of nonvascular plants are usuallyno more than a few cells thick, andwater and nutrients travel from onecell to another by the relatively slowprocesses of osmosis and diffusion.

The evolution of vascular tissueswas of major importance in enablingplants to survive in the many habitatsthey now occupy on land. Vascularplants can live farther away fromwater than nonvascular plants. Also,because vascular tissues includethickened cells called fibers that helpsupport upright growth, vascularplants can grow much larger thannonvascular plants.

Reproductive strategiesAdaptations in some land plants

include the evolution of seeds. A seedcontains an embryo, along with a foodsupply, covered by a protective coat,Figure 21.4. Seeds protect the zygoteor embryo from drying out and mayalso aid in dispersal. Recall that a sporeconsists only of a single haploid cellwith a hard, outer wall. Land plantsreproduce by either spores or seeds.

In non-seed plants, which includemosses and ferns, the sperm swimthrough a film of water to reach theegg. In seed plants, which include allconifers and flowering plants, spermare able to reach the egg withoutswimming through a continuous filmof water. This difference is one reasonwhy non-seed plants require moisterhabitats than most seed plants.

Alternation of generationsAs in algae, the lives of all plants

consist of two alternating stages, orgenerations, as shown in Figure 21.5.The gametophyte generation of a

578 WHAT IS A PLANT?

Seedcoat

Foodsupply

Embryo

Figure 21.4A seed contains anembryo, along with afood supply, coveredby a protective coat.

GAMETOPHYTE (n)

Spores (n)

Meiosis

SPOROPHYTE (2n)

Mitosis

Fertilization

Femalegamete (n)

Malegamete (n)

Figure 21.5 The lives of allplants consistof two gener-ations.

578

Purpose Students will analyze diagramsand detect errors in labeling.

Process Skillsanalyze information, conceptmapping, interpret scientificillustrations, sequence, think crit-ically

Teaching Strategies■ Make sure that students havereviewed the concept of alterna-tion of generations prior to thislab.■ Allow students to work insmall groups.■ Review the terms haploid anddiploid with students.■ Point out that gametophytesalways form gametes while sporo-phytes always form spores.

Thinking Critically

1. Gametophytes always formgametes by the process ofmitosis; gametophytes arealready haploid in chromo-some number; gametophytesdo not form spores, gametesare always haploid, notdiploid.

2. Sporophytes always formspores by meiosis; chromo-some number of spores willbe haploid or 6.

3. Diagram B follows A with anarrow connecting spores togametophyte stage and anarrow connecting gametes tosporophyte stage. Studentsmay also indicate fertilizationof gametes prior to formingsporophyte.

Performance Ask studentsto draw a complete life cycle of aplant having a diploid chromo-some number of 20. Labelsshould be added to the stages asin Diagrams A and B. Use thePerformance Task AssessmentList for Scientific Drawing inPASC, p. 55.

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Problem-Solving Lab 21-1Problem-Solving Lab 21-1 plant is responsible for the develop-ment of gametes. All cells of thegametophyte, including the gametes,are haploid (n). The sporophyte gen-eration is responsible for the produc-tion of spores. All cells of the sporo-phyte are diploid (2n) and are pro-duced by mitosis. The spores areproduced in the sporophyte plantbody by meiosis, and are thereforehaploid (n).

The life cycles of all plants includethe production of haploid spores. Innon-seed vascular plants such asferns, the spores have hard outer coverings and are released directlyinto the environment, where theygrow into haploid gametophytes. Inseed plants, such as conifers andwildflowers, the spores are retainedby the parent plant and develop intogametophytes of only a few cells insize that are retained within thediploid sporophyte. Seed plantsrelease the new sporophytes into theenvironment in the form of seeds.The gametophytes of non-seedplants are usually much larger thanthe gametophytes retained in theseeds of seed plants. Use the Problem-Solving Lab on this page to furtherexplore the differences between thegametophyte and sporophyte genera-tions of plants.

21.1 ADAPTING TO LIFE ON LAND 579

How do gametophytes and sporophytes compare?Plants have two different phases in their life cycle. One phaseis called the gametophyte generation, and the other phase iscalled the sporophyte generation.

AnalysisDiagram A shows the gametophyte generation of a

plant. This particular plant has a haploid chromosome num-ber of 6. Examine the diagram carefully and look for errorsthat may be present.

Diagram B shows the sporophyte generation of a plant.The particular plant has a diploid chromosome number of 12.Examine the diagram carefully and look for errors that maybe present.

Thinking Critically1. List the errors observed in Diagram A and explain why

they are incorrect.2. List the errors observed in Diagram B and explain why

they are incorrect.3. Copy corrected Diagrams A and B so that they connect

to one another and form a complete life cycle diagram of a plant.

Problem-Solving Lab 21-1Problem-Solving Lab 21-1 AnalyzingInformation

Section AssessmentSection Assessment

Understanding Main Ideas1. What are three characteristics that plants share

with algae?2. Explain how the development of the cuticle and

the vascular system influenced the evolution ofplants on land.

3. How do seeds and spores differ? What are thebenefits of producing seeds?

4. List the sequence of events involved in the alter-nation of generations in land plants. Do allplants have alternation of generations?

Thinking Critically5. Explain why vascular plants are more likely to sur-

vive in a dry environment than nonvascular plants.

6. Making and Using Tables Make a table of thedifferent adaptations plants have evolved thatallow them to live on land. Include how eachspecific adaptation helps a plant survive on land.For more help, refer to Organizing Informationin the Skill Handbook.

SKILL REVIEWSKILL REVIEW

Gametophyten = 6

Plant stage

Meiosis

Process Male sporen = 12

Female gameten = 12

Sporophyten = 12

Plant stage

Mitosis

Process

Sporesn = 12

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3 AssessCheck for UnderstandingHave students explain the differ-ences between the followingword groups.

(a) seed—spore(b) vascular—nonvascular(c) sporophyte—gametophyte

ReteachHave students prepare an outlinethat addresses the following: (a)evidence that land plants evolvedfrom green algae, (b) adaptationsof land plants that enable them tosurvive on land, and (c) the majorfunctions of leaves, roots, andstems.

ExtensionVisual-Spatial Have studentsobserve a plant growing

outside the school, and list traitsthat allow it to live on land.

Knowledge Have studentsexplain how each of the followinghelp plants survive on land: (a)thin leaves, (b) waxy cuticle, (c)roots, (d) supportive tissue instems, (e) thick covering aroundgametes.

4 CloseDiscussion

Logical-Mathematical Havestudents correlate the fol-

lowing items with a plant struc-ture. Ask them to give reasons fortheir choices. Items: drinkingstraw, waxed paper, skin pores,Velcro, steel beams, bag of sugar,roof shingles. L1

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PortfolioPortfolio

Diagramming Alternation ofGenerations

Visual-Spatial Have students pre-pare a simple flow chart diagram

that depicts alternation of generations.The diagram must include these terms:gametophyte generation, sporophytegeneration, spore, gamete, diploid, hap-loid, mitosis, and meiosis.

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MEETING INDIVIDUAL NEEDS MEETING INDIVIDUAL NEEDS

Visually ImpairedKinesthetic Provide students withwaxy leaves so they can feel the cu-

ticle. Leaves such as philodendron, hoya,and maple are good specimens to use forthis activity.

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Section AssessmentSection AssessmentSection Assessment1. Cell walls composed of cellulose, the

same types of chlorophyll for photosyn-thesis, and storage of food as starch.

2. A cuticle reduces water loss and a vascular system transports food, water,and minerals to all parts of the plant.

3. Seeds have a protective coat and contain a diploid embryo. Spores are asingle haploid cell with a hard, outer

wall. Seeds protect an embryo fromdrying out and aid in dispersal.

4. Sporophytes form spores via meiosis,spores form gametophytes that formgametes via mitosis, gametes fuse toform a new sporophyte. Yes, all landplants have alternation of generations.

5. Vascular plants have tubelike tissuesthat transport water and nutrients,

whereas nonvascular plants use osmo-sis and diffusion, which requires a closeassocation with water.

6. Table should include the following:preventing water loss, leaves carry outphotosynthesis, roots, transportingmaterials, and reproductive strategies.

579

POTATOES — A South American native, the potato arrived inthe United States via Europe. This nutritious root vegetablecontains many essential amino acids. Potatoes also containvitamins B and C and the minerals calcium and iron.

OATS — Oats make excellent food for both animals andhumans. Containing from 10 to 16 percent protein, oats arelow in fat and high in carbohydrates, proteins, B vitamins,fiber, and minerals. Native to northern Europe, oats growwell in poor soils as well as in cool, wet climates.

BARLEY — Barley was probably thefirst grain crop grown by humans.The Egyptians grew barley in6000 B.C. The world’s fourthlargest cereal crop, barley growsfast and is able to withstand harshgrowing conditions in rugged cli-mates such as Lapland and theHimalayas.

SORGHUM — Since prehistorictimes, sorghum has been a majorfood crop in Africa. Because of itsextensive root system, sorghum isespecially drought resistant, pro-viding food for people and hayfor cattle.

POTATOES, PERU

581

SORGHUM, SOMALIA

581

Teaching Strategies■ Supply students with blankmaps of the United States. Askthem to color in those areas thatare primarily corn- and wheat-growing zones. Have them addlabels to identify each crop.■ Supply students with a globaloutline map. Have them label onthe map where early agriculturebegan—the Tigris and theEuphrates, Nile Valley, and IndusRiver region.

Tying to PreviousKnowledge■ Have students review the

process of fermentation andallow them to infer how corncan be used in the process toproduce alcohol. Corn serves asthe food source for yeast.

EnrichmentIntrapersonal Ask studentsto determine the differences

between the wheat used for pasta(T. durum) and that used forbread (T. vulgare). Have themfind out what some of the differ-ent physical properties arebetween these starches and whyone is more suitable than theother for bread or pasta products.

Visual LearningVisual-Spatial Obtain a copyof the USDA food pyramid.

Ask students to examine the textand photos of the agriculturalproducts shown here and deter-mine where they fit in a daily bal-anced diet as described by theUSDA food pyramid. How manyparts of the food pyramid comefrom plants? How important areplants for human nutrition?

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FOCUS ON

Agriculture was perhaps thesingle most important develop-ment in human history. It is noaccident that the beginnings ofcivilization occurred in produc-tive farming areas. Today, manyfarmers grow just one foodcrop. Monoculturesenable farmers to usemachinery for planting,cultivating, and har-vesting. However,monocultures are veryvulnerable to disease.Pest infestations canspread rapidly, wipingout an entire season’scrop. To combat thisproblem, farmershave begun to use nativespecies that are less susceptibleto disease. Scientists are alsousing genetic engineeringtechniques to make cotton, corn,and other crop plants moreinsect resistant.

CORN — Farmers in the UnitedStates use more acreage to growcorn than any other crop. Livestockconsume most of the corn crop, but a significant portion also goes tomanufacture starch, oil, sugar, meal,breakfast cereals, and alcohol.

WHEAT — Nearly one-third of all land in the world used for cropproduction is planted in wheat.Wheat probably originated inthe Middle East and was an impor-tant food for the ancientMesopotamian, Egyptian, andIndus civilizations.

RICE — Most humans equate ricewith survival. In Asia, rice is thebasis of almost all diets. More than95 percent of the world’s rice cropis used to feed humans. Rice is the only grain that can grow sub-merged in water.

Plants for PeopleAGRICULTURE

RICE, BALI

580

WHEAT, UKRAINE

580

Focus On Plants for People

Purpose Students will discover the role ofagriculture, silviculture, and hor-ticulture in producing plants forfood, shelter, medicine, and plea-sure.

BackgroundScientific names for speciesdescribed in this feature are asfollows: corn, Zea mays; rice,Oryza sativa; wheat, Triticumdarum var. vulgare: potato,Solanum tuberosum; oats, Avenasativa; barley, Hordeum vulgare;sorghum, Sorghum bicolor.

Teaching Strategies■ Have students read this fea-ture. Then have them work incooperative groups to prepare atable of all the plants described.Along the left side, have them listthe crop species. Across the top,have them use the headings:Kingdom, Division, Class, Fam-ily. Advise students to refer to theClassification Appendix A forhelp in the completion of theirtable. Note: Not all plants arelisted in the appendix.

■ Have students write a shortparagraph that describes the rela-tive dependence of humans onplants as food sources. L2

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PortfolioPortfolio

Commercial AgricultureLinguistic Have students researchthe origin of a particular commercial

crop and write a brief report on their find-ings. The report can be placed in theirportfolios. PP

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MEETING INDIVIDUAL NEEDS MEETING INDIVIDUAL NEEDS

English Language LearnersVisual-Spatial Ask students to collectphotos of plants from magazines and

ask if any of them illustrate any of themain products obtained through agricul-ture.

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Nutritional Values of FoodsHave students prepare a chart comparingthe fat and protein content of four of thefoods mentioned in “Plants for People.”Students should explain which foodswould provide more energy and why. L2

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VIDEODISCThe Infinite Voyage: A Taste ofHealth, Pima Indians: Old Traditions

in Nutrition (Ch. 1)5 min.!7-8J"

Pima Indians: Coping With Disease (Ch. 2)7 min.!77BB"

HORTICULTUREMost of the plants you are familiar with were originally brought from distant lands by naturalists and explorers. By preserving and cultivatingthese species, horticulturalists gave us a legacy of beautiful and usefulflowers and foods. Selective breeding, grafting, and more recently, geneticengineering are some methods used by plant scientists.

1

EXPANDING Your View

APPLYING CONCEPTS Take a piece of paper and make two columns. Inthe left column, list all of the products essential to your life that comefrom plants and/or agriculture. In the right column, list all of the essentialproducts that do not come from plants and/or agriculture. Now write aparagraph summarizing the role of plants in your life.

FLOWERS AND MEDICINAL PLANTS—Flowering bulbs, roses, scentedherbs, and ornamentals of all kindshave been a source of pleasure forgenerations. Plants have been usedfor medicinal purposes for thousandsof years. Today plants continue tobe a major source of pharmaceuti-cals and herbal remedies.

FRUITS — Trees are a source forone of the world’s favorite foods—fruit. Acorns, walnuts, and pecansare among the dry fruits used asfood by wildlife and humans. Fleshyfruits include oranges, apples, pears,apricots, and cherries.

VEGETABLES — Vegetables wereamong the first plants cultivated byhumans. Green cabbage, water-cress, and radishes—members ofthe mustard family—were knownto Egyptians and Romans in theBronze Age. Root crops such asbeets, carrots, potatoes, and turnipsare highly prized for fiber andnutrients and because they can bestored easily over winter.

FRUIT MARKET, AFGHANISTAN

FLOWERING BULBS, HOLLAND

583

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ActivityKinesthetic Have studentstest a variety of plant roots

for the presence of starch. Havethem use thin slices of radish,turnip, and potato and add a fewdrops of iodine/potassium iodidesolution to the root. A blue-blackcolor indicates the presence ofstarch. As a control, have themadd a drop of iodine solution to asmall clump of corn starch. Askthem to write a report of theirobservations for their portfolios.

Answers to Expanding YourViewExcept for transportation, com-munication, certain services, andproducts composed of metals,almost all human basic needs aretied to plants.

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SILVICULTUREOften confused with forestry, silvi-culture includes the growing oftrees for lumber and paper and for food crops, such as apples andpecans. Oranges, cloves, nuts, andolives are some of the foods andspices grown on trees. Trees arealso sources of medicines, such as aspirin, originally derived fromthe bark of the willow tree, andquinine, from the Cinchona tree,used to treat malaria. Trees helpreduce air pollution and replenishthe oxygen we breathe.

CHEMICALS AND SPICES — Wood is the source ofmany chemicals including wood alcohol, latex forrubber, and cellulose used to make paper.Charcoal and rayon as well as spices, such as cin-namon and cloves, also are tree products. Taxol,an extract from the bark of a Pacific Coast yewtree, is currently being used to fight cancer.

LUMBER AND FUEL — When people think of forest products, they often think of lumber. A common building material, wood is easy to

work with, durable, relatively abundant, andlightweight—making it ideal for home construc-

tion. Easy to transport and to store, wood is also asource of fuel throughout much of the world.

LUMBER INDUSTRY,WASHINGTON STATE

RESEARCH ON FRUIT TREES, MARYLAND

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BARK FOR MEDICINAL USE, KENYA

582

BackgroundQuinine, an antimalarial chemi-cal derived from the bark of vari-ous species of Cinchona trees, wasused by the Andean Indiansbefore the European discovery ofthe New World.

Cinnamon is derived from thebark of Cinnamommum zeylan-cium.

Teaching Strategies■ Have students work in cooper-ative groups to compile a list ofdifferent nuts that are from trees,and draw a map that shows wherethese are grown around theworld. Responses may includealmond, Brazil nut, cashew,hazelnut, pecan, pistachio, wal-nut, and chestnut.

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Internet Address Book

Note Internet addresses that you find useful in the spacebelow for quick reference.

VIDEODISCSTV: Plants, How Plants Are UsedUnit 3, Side 2, 13 min. 15 sec.

How Plants Are Used (in its entirety)

!7.E=^$Å"

Hepatophyta Hepatophytes (heh PAH toh fites)

are small plants commonly called liver-worts because the flattened body ofthe plant resembles the lobes of ananimal’s liver. There are two kinds ofliverworts: thallose liverworts andleafy liverworts. Thallose liverwortshave a broad body that looks like alobed leaf. Leafy liverworts arecreeping plants with three rows ofthin leaves attached to a stem.Liverworts are nonvascular plants.They grow only in moist environ-ments because they use osmosis anddiffusion to transport water andnutrients. Studies comparing the bio-

chemistry of different plant divisionssuggest that liverworts may be theancestors of all plants.

Anthocerophyta Anthocerophytes (an THOH ser oh

fites) are also small plants. Thesporophytes of these plants, whichresemble the horns of an animal, givethe plants their common name—hornworts. These nonvascular plantsgrow in damp, shady habitats andrely on osmosis and diffusion totransport nutrients.

21.2 SURVEY OF THE PLANT KINGDOM 585

OriginWORDWORD

hepato-From the Greekword hepar, mean-ing “liver.”Hepatophytes haveliver-shaped game-tophytes.

Figure 21.6The plant kingdom includes sevendivisions of non-seed plants.

Tree ferns arepterophytes. ThisCyathea arboreacan be foundgrowing in damp,tropical forests.

BB

Selaginella, a spike moss, is a lycophyte. Lycophytesare vascular plants adaptedto moist environments.

AA

Equisetum is asphenophyte. Ithas roots, stems,and leaves, but the stems arehollow and appear jointed.

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Sphagnum is abryophyte. It growsin peat bogs.

EE

Anthoceros, a hornwort,is an Anthocerophyte. It is found in moist,shady habitats.

FF

Marchantia is ahepatophyte.It is found ondamp rocks.

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Psilotum sporophyteshave simple stemsbut no leaves.

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2 TeachDisplayMake a bulletin board display ofa variety of plants from differentdivisions.

Section

584 WHAT IS A PLANT?

Phylogeny of Plants Many geological and climate

changes have taken place since thefirst plants became adapted to life on land. Landmasses have movedfrom place to place over Earth’s sur-face, climates have changed, and bod-ies of water have formed and disap-peared. Hundreds of thousands ofplant species evolved, and countlessnumbers of these became extinct asconditions continually changed.These processes of evolution andextinction continue to be affected bylocal and global changes. As plantspecies evolved in this changing land-scape, they retained many of their oldcharacteristics and also developednew ones. These processes of evolu-tion and extinction continue today.

Botanists use plant characteristicsto classify plants into twelve divisions.Recall that a plant division is similarto a phylum in other kingdoms. Thehighlights of plant evolution includeorigins of plants from green algae,the development of vascular tissue,the production of seeds, and the for-mation of flowers. The production ofseeds can be used as a basis to sepa-rate the divisions into two groups—non-seed plants and seed plants.

Non-seed PlantsThere are seven divisions of non-

seed plants, which are shown inFigure 21.6. These plants producehard-walled reproductive cells calledspores. Non-seed plants may beeither vascular or nonvascular.

Members of the plant kingdom arefound all over the world. Manyspecies are widespread, but some

grow in only one area. For example,Sarracenia oreophila, commonly knownas the green pitcher plant, is found onlyin the Southeastern United States.Others, such as the cinnamon fern, havea much wider distribution. These twoplants also illustrate two differ-ent reproductive strategies.While both the fern andpitcher plant produce spores,the pitcher plant also producesseeds.

SECTION PREVIEW

ObjectivesDescribe the phylogenic relationshipsamong divisions ofplants.Identify the twelveplant kingdom divisions.

Vocabularyfrondcone

Cinnamon ferns in forest and green

pitcher plant,Sarracenia oreophila,

with flowers (inset)

21.2 Survey of thePlant Kingdom

584

Section 21.2

PrepareKey ConceptsStudents survey the 12 majorplant divisions.

Planning■ Collect pictures of plants for

the bulletin board.■ Collect pine needles and leaves

for the Quick Demo

1 FocusBellringer Before presenting the lesson, display Section Focus Trans-parency 51 on the overhead pro-jector and have students answerthe accompanying questions.

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BIOLOGY: The Dynamics of Life SECTION FOCUS TRANSPARENCIES

Use with Chapter 21,Section 21.2

This moss and liverwort have no vascular tissues. How mightthis limit the types of habitat these plants can survive in?

How else might the lack of vascular tissue limit these plants?

11

22

Transparency Bryophytesand Hepatophytes

51 SECTION FOCUS

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Moss Liverwort

Cultural DiversityEthnobotany

Interpersonal Introduce stu-dents to the growing field of

ethnobotany, the study of how native cul-tures use plants. Ethnobotany has becomeincreasingly important to the developmentof new drugs by pharmaceutical companies.One firm, Shaman Pharmaceuticals in

California, sends researchers into SouthAmerican, Asian, and African tropical foreststo ask healers about the medications theyderive from plants. Have students researchand write reports about the medicinal usesof plants in different cultures in both con-temporary and historical perspectives. L2

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Quick DemoQuick Demo

Visual-Spatial Show stu-dents pine needles and

broad-leaves and ask them tocompare and contrast theirfeatures.

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PortfolioPortfolio

Hepatophytes and Bryophytes Visual-Spatial Have students drawpictures or find magazine photos of

hepatophytes and bryophytes. Studentsshould include labels that indicate thesimilarities and differences between thetwo plants.

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BIOLOGY JOURNAL BIOLOGY JOURNAL

Identifying Seed Plants Visual-Spatial Ask students to pre-pare a concept map that will help

other students to identify seed plants.Suggest they include pictures from maga-zines or drawings as part of their conceptmap.

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CD-ROMBiology: The Dynamicsof Life

Exploration: The Five KingdomsDisc 3

Knowledge Show stu-dents pictures of plants from sev-eral divisions. Have them identifythe division to which each be-longs.

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AssessmentAssessment

VIDEODISCSTV: PlantsWhat is a Plant?

Unit 1, Side 1, 3 min. 40 sec.Types of Plants

!84d5L$Ñ"Resource ManagerResource Manager

Section Focus Transparency 51and Master

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sphenophytes contain large depositsof silica. Although primarily a fossilgroup, about 15 species of spheno-phytes exist today. All present-dayhorsetails are small, but their fossilrelatives were the size of trees.

Pterophyta Pterophytes (ter OH fites), ferns,

are the most well-known and diversegroup of non-seed vascular plants.Ferns were abundant in Paleozoicand Mesozoic forests. They haveleaves that vary in length from 1 cmto 500 cm. The large size and com-plexity of these leaves, also calledmegaphylls, is one difference between

pterophytes and other groups ofseedless vascular plants. These leavesare called fronds. Although ferns arefound nearly everywhere, most growin the tropics.

Seed Plants Seed plants produce seeds, which

in a dry environment are a moreeffective means of reproduction thanspores. Seeds consist of an embryonicplant and a food supply covered by ahard protective seed coat. All seedplants have vascular tissues. Examplesfrom the seed plant divisions areshown in Figure 21.7.

Figure 21.7 Plants classified into the five divisions of seed plants produceseeds covered by tough, protective seed coats.

Ginkgo biloba, themaidenhair tree, is nolonger found in thewild, although it con-tinues to be cultivatedin many countries,including the UnitedStates.

DD

Wildflowers can be found innearly every environment onEarth. This wildflower, calledchicory, is an anthophyte.

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Cycads are often mistaken forferns or small palm trees.

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Welwitchsiamirabilis is foundin harsh desertenvironments inAfrica. The leaves ofthis gnetophyte cangrow to 2 m long.

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Pinus banksiana, the jackpine, keeps its cones closeduntil a fire passes over them,an example of an adaptationto extreme conditions.

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Bryophyta Bryophytes (BRI uh fites), mosses,

are nonvascular plants. Like liverwortsand hornworts, mosses rely on osmosisand diffusion to transport water andnutrients. However, some mosses haveelongated cells that conduct water andsugars. Moss plants are usually lessthan 5 cm tall and have leaves that areusually only one to two cells thick.Their spores are formed in capsules.

Psilophyta Psilophytes, also known as whisk

ferns, consist of thin, green, leaflessstems. The psilophytes are uniqueamong vascular plants because theyhave neither roots nor leaves. Smallscales cover each stem. Scales are flat,rigid, overlapping structures. Most ofthe 30 species of psilophytes aretropical or subtropical, although onegenus is found in the southernUnited States.

Lycophyta Lycophytes (li KOH fites), the club

mosses, are vascular plants adaptedprimarily to moist environments.Lycophytes have stems, roots, andleaves. Their leaves, although verysmall, contain vascular tissue. Speciesexisting today are usually less than 25centimeters high, but their ancestorsgrew as tall as 30 meters and formeda large part of the vegetation ofPaleozoic forests. The plants of theseancient forests have become coal andare now used by people for fuel. Trythe MiniLab on this page to explorethe similarities and differencesbetween modern and fossil lycophytes.

Sphenophyta Sphenophytes (sfe NOH fites), the

horsetails, are vascular plants. Theyhave hollow, jointed stems sur-rounded by whorls of scalelike leaves.The cells covering the stems of some

Looking at Modern and Fossil Plants Many modern-dayplants have relatives that are known only from the fossilrecord. Are modern-day plants similar to their fossil relatives?Are there any differences?

Procedure! Examine a preserved or living sample of Lycopodium, a

club moss. CAUTION: Wear disposable latex gloves whenhandling preserved material.

@ Note and record the following observations:a. Does the plant grow flat or upright like a tree? b. Describe the appearance of its leaves and its stem.c. Measure the plant’s height and diameter in centi-

meters.# Diagram A is a representation of a fossil relative called

Lepidodendron. Record the same observations (a–c).$ Repeat steps a-c only this time use a preserved or living

sample of Equisetum, a horsetail. Compare it to DiagramB, a representation of a fossil relative called Calamites.

Analysis1. Describe the similarities and differences between

Lycopodium and Lepidodendron. Do your observationsjustify their closeness as relatives? Explain.

2. Describe the similarities and differences betweenEquisetum and Calamites. Do your observations justifytheir closeness as relatives? Explain.

MiniLab 21-2MiniLab 21-2 Comparing and Contrasting

2 meters

1 meter

20 meters

30 meters

A BA B

586 WHAT IS A PLANT?

586

PurposeStudents will compare livingplants from two different divi-sions with their fossil relatives.

Process Skillsclassify, collect data, compare andcontrast, draw a conclusion, mea-sure in SI, observe and infer

Teaching Strategies■ Living and preserved samplesof club moss and horsetail areavailable from biological supplyhouses.■ Caution students about rub-bing their eyes when workingwith preserved materials.■ Student observations can beboth qualitative and quantitative.Review the meaning of theseterms before students start thisactivity.■ Remind students that mea-surements in diagrams are inmeters and the comparison asksfor the same measurements incentimeters. Review conversionfrom meters to centimeters ifnecessary.

Expected ResultsStudents will find a number ofsimilarities and some differencesbetween the living plants andtheir fossil relatives. Numbers ofsimilarities and differences willdepend on the thoroughness ofstudent observations.

Analysis1. Similarities—green, grow

upright, have scalelike leaves.Differences—tall and thickfossil stem, short and thin liv-ing stem, leaves on top of fos-sil stem, ridged surface offossil stem, leaves on livingstem. Student answers on thecloseness of the relationshipmay vary. If going by generalappearance, students mayagree that they are closelyrelated. If using the totalnumber of similarities anddifferences, students may dis-agree.

2. Similarities—green, growupright, leaves are in whorls,

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leaves are small, rings on stem.Differences—fossil has branches whileliving is one single stem, fossil is tallerand thicker, living plant leaves appear tobe much smaller than fossil. Studentanswers on the closeness of the relation-ship may vary. If going by generalappearance, students may agree thatthey are closely related. If using the totalnumber of similarities and differences,students may disagree.

Knowledge Ask students to find outhow long ago the fossil plant examples usedin this MiniLab lived on Earth. Use thePerformance Task Assessment List for UsingMath in Science in PASC, p. 29. L2

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AssessmentAssessment

CD-ROMBiology: The Dynamicsof Life

BioQuest: Biodiversity ParkDisc 3, 4Video: Fern Development, Disc 3

VIDEODISCThe Infinite Voyage:To the Edge of the

Earth, The Tropical Rain Forest(Ch. 5), 8 min.

!7U`H"

DisplayVisual-Spatial Have studentsphotograph a variety of

plants or bring in pictures of vari-ous plants cut from magazines.As a class, develop a bulletinboard display that places eachplant pictured, along with itsname, in its correct division. Usethe completed display as a teach-ing tool throughout the unit.

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MEETING INDIVIDUAL NEEDS MEETING INDIVIDUAL NEEDS

English Language Learners/Hearing Impaired

Visual-Spatial Have students useFigure 21.7 and the text to make a

table that compares conifers and antho-phytes. The table should have two columnslabeled Similarities and Differences. Havestudents include physical differences andsimilarities.

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Resource ManagerResource Manager

BioLab and MiniLabWorksheets, p. 98

Basic Concepts Transparency33 and Master

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Section AssessmentSection Assessment

Understanding Main Ideas1. What is the primary difference between the

seeds of conifers and anthophytes?2. Why are seeds an important adaptation? What

plant divisions produce seeds? Which plant divisions do not produce seeds?

3. Explain why pterophytes tend to be larger thanbryophytes.

4. How are anthophytes and anthocerophytes similar? How are they different?

Thinking Critically5. In which division would you expect to find apple

trees? Why?

6. Making a Table Make a table of the twelveplant divisions that includes seed plants, non-seed plants, vascular plants, nonvascular plants,and seeds in fruits. For more help, refer toOrganizing Information in the Skill Handbook.

SKILL REVIEWSKILL REVIEW

cancer-fighting drugs. Read moreabout medicinal plants in the Health Connection at the end of thischapter.

AnthophytaAnthophytes (an THOH fites),

commonly called the floweringplants, are the largest, most diversegroup of seed plants living on Earth.There are approximately 240 000species of Anthophytes. Fossils ofthe Anthophyta date to only theCretaceous period, 130 million yearsago. Anthophytes produce flowersand seeds enclosed in a fruit. This

division has two classes: the mono-cotyledons (mahn uh kaht ul EED

unz) and dicotyledons (di kaht ulEED unz). You will learn more aboutthe distinctions between monocotsand dicots when you read aboutanthophyte tissues.

Table 21.1 lists some informationabout the twelve divisions of theplant kingdom. See if you can recog-nize any of the common names ofthe plants. You can further explorethe similarities and differencesamong the twelve divisions of plantsin the Problem-Solving Lab, shownon the previous page.

21.2 SURVEY OF THE PLANT KINGDOM 589

OriginWORDWORD

conifero- From the Latinword conifer, mean-ing “cone bearing.”Many plants in the divisionConiferophyta produce their seedson cones.

Table 21.1 The twelve divisions of the Plant Kingdom

Approximate Division Common Name Number of Species Examples

Anthocerophyta Hornworts 100 Anthoceros

Hepatophyta Liverworts 6500 Marchantia

Bryophyta Mosses 10 000 Sphagnum

Psilophyta Whisk Ferns 10-13 Psilotum

Lycophyta Club Mosses 1000 Lycopodium

Sphenophyta Horsetails 15 Equisetum

Pterophyta Ferns 12 000 Nephrolepis

Cycadophyta Cycads 100 Cycas

Ginkgophyta Ginkgoes 1 Ginkgo

Coniferophyta Conifers 550 Pinus

Gnetophyta Gnetophytes 70 Welwitschia

Anthophyta Flowering Plants 240 000 Rosa

3 AssessCheck for UnderstandingQuiz students orally about themajor characteristics of the 12divisions.

ReteachVisual-Spatial Have studentsconstruct a table organizing

the 12 divisions under two head-ings: non-seed and seed plants.

ExtensionHave students prepare a key thatwill enable them to distinguishamong the 12 plant divisions.Encourage students to photocopytheir keys and share them withtheir classmates.

Knowledge Using thephotos in Figures 21.6 and 21.7,have students explain why eachplant belongs to its particulardivision. L2

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AssessmentAssessment

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4 CloseActivityDivide the class into smallgroups, assigning each a differentbiome. Ask them to predict whatplants might inhabit their biome,identify the plant divisions, andexplain their reasoning.

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CycadophytaCycads (SI kuds) were abundant

during the Mesozoic era. Today,there are about 100 species of cycads,palmlike trees with scaly trunks.Cycads may be very short in statureor they may be 20 meters or more inheight. Cycads produce male andfemale cones on separate trees.Cones are scaly structures that sup-port male or female reproductivestructures. Seeds are produced in

female cones. Male cones producelarge clouds of pollen. The cones ofcycads may be as long as 1 m.

GnetophytaThere are three genera of gneto-

phytes (nee TOH fites), each of whichis quite distinct. Gnetum includesspecies of trees and climbing vines;Ephedra includes shrubby species; andWelwitschia, found only in SouthAfrica, has a short stem that grows as a large, shallow cap. The leaves of this plant grow from the base ofthe stem. These seed plants grow inthe desert and can live to be 100years old.

GinkgophytaThis division has only one living

species, Ginkgo biloba, a distinctivetree with small, fan-shaped leaves.Like cycads, ginkgos (GING kohs)have separate male and female trees.The seeds produced by the femaletrees have an unpleasant smell, soginkgos planted in city parks areusually male trees. Ginkgos arehardy and resistant to insects and toair pollution. You can learn moreabout the suitability of differentplants for various environments inthe BioLab at the end of the chapter.

ConiferophytaThese are the conifers

(KAHN uh furz), cone-bearing treessuch as pine, fir, cypress, and red-wood. Conifers are vascular seedplants that produce seeds in cones.Unlike Anthophytes, the seeds ofconifers are not protected by a fruit.Species of conifers can be identifiedby the characteristics of their needle-like or scaly leaves. Bristlecone pines,the oldest known living trees in the world, are members of thisplant division. Another type ofconifer, the Pacific yew, is a source of

588 WHAT IS A PLANT?

What trend in size is seen with gametophyte and sporo-phyte generations? All plants undergo alternation of gen-erations. There is a specific trend, however, that occurs in sizeas one goes from one plant division to the next.

Analysis The following graph shows the trend that occurs within

the plant kingdom as one compares the size of sporophyteand gametophyte generations in three major divisions.

Thinking Critically1. Describe the trend that occurs to the size of the gameto-

phyte generation as one moves from Bryophytes toAnthophytes.

2. Describe the trend that occurs to the size of the sporo-phyte generation as one moves from Bryophytes toAnthophytes.

3. Estimate the size of the gametophyte generation com-pared with the sporophyte generation in:a. Coniferophyta. Explain.b. Lycophyta. Explain.

4. You are looking at a giant redwood tree. Which genera-tion is it and how do you know?

Problem-Solving Lab 21-2Problem-Solving Lab 21-2

Gam

etop

hyte

gen

erat

ion

Spor

ophy

te g

ener

atio

n

Increasing sporophyte size

BRY

OPH

YTA

PTER

OPH

YTA

AN

THO

PHY

TA

Decreasing gametophyte size

OriginWORDWORD

ginkgo- From the Chineseword yin-hing,meaning “silverapricot.”Ginkgophytaspecies produceapricot coloredseeds.

Applying Concepts

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PurposeStudents will analyze a graph anddetect trends that occur in thesize of the gametophyte andsporophyte generations as theymove through the various plantdivisions.

Process Skillsapply concepts, think critically,compare and contrast, draw aconclusion

Teaching Strategies■ Ask students to sequence theplant divisions from Bryophyta toAnthophyta prior to doing thislab. This will allow them to referto their lists as they complete theanalysis section.

Thinking Critically

1. Gametophyte generationbecomes smaller.

2. Sporophyte generation be-comes larger.

3. a. large sporophyte, smallgametophyte; divisionwould be located directlyto the left of Anthophytes

b. large gametophyte, smallsporophyte; division wouldbe located close to theright of Bryophyta

4. Redwoods are grouped in thedivision Coniferophyta.Therefore, the large genera-tion is the sporophyte.

Knowledge Ask studentsto predict the laboratory toolsneeded to study the gametophyteand sporophyte generations of amoss plant and a rose. Use thePerformance Task List forDesigning an Experiment inPASC, p. 23. L2

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Problem-Solving Lab 21-2Problem-Solving Lab 21-2

CD-ROMBiology: The Dynamics of LifeVideo: Giant Redwoods

Disc 3

The BioLab at theend of the chaptercan be used at thispoint in the lesson.

INTERNETINTERNET

Section AssessmentSection AssessmentSection Assessment1. Anthophyte seeds are encased in fruits;

conifer seeds are produced on cones.2. Seeds provide protection and a food

supply for the embryo and aid in dispersal. Seed: Cycadophyta, Gneto-phyta, Ginkgophyta, Coniferophyta,and Anthophyta. Non-seed: Anthocero-phyta, Hepatophyta, Bryophyta, Psilo-phyta, Lycophyta, Sphenophyta, and

Pterophyta. 3. Ferns have vascular tissues that trans-

port water and provide support.4. Both show alternation of generations

and are land plants. Anthocero-phytesare non-seed, nonvascular plants;anthophytes are vascular seed plants.

5. Apple trees anthophytes because theyproduce flowers and fruit.

6. Non-seed nonvascular: Anthocero-phytes, Hepatophytes, and Bryo-phytes; Non-seed, vascular: Psilo-phytes,Lycophytes,Sphenophytes, andPterophytes; Seed, vascular: Cycado-phytes,Gnetophytes,Ginkgophyte,Coniferophytes; Anthophytes; Seeds infruits, vascular: Anthophytes.

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Resource ManagerResource ManagerReinforcement and Study Guide,

pp. 95-96Content Mastery pp. 105, 107-108 L1

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21.2 SURVEY OF THE PLANT KINGDOM 591

1. Defining Operationally Explainthe difference between trees classified as either Coniferophytaor Anthophyta.

2. Analyzing Was the informationprovided on the Internet helpfulin completing your data table?Explain your answer.

3. Thinking Critically What do you consider to be the mostimportant characteristic whendeciding on the most suitable tree for your community? Explain your answer.

4. Using the Internet Using theinformation you gathered fromthe Internet, which tree specieswould most likely be the:a. most suitable for your commu-

nity? Explain your answer.

b. least suitable for your commu-nity? Explain your answer.

5. Applying Explain why tree selections would differ if yourcommunity were located in: a. Tucson, Arizonab. Los Angeles, Californiac. Fairbanks, Alaska

ANALYZE AND CONCLUDEANALYZE AND CONCLUDE

Tree Name (common name)

Scientific Name

Kingdom

Division

Soil/Water Preference

Temperature Tolerance

Height at Maturity

Speed of Growth

General Shape

Disease Resistance/Problems

Special Care

Leaf Shape

Shade Provider

Additional Information

1

Data Table

2 3 4 5

Flowering dogwood,Cornus florida

Southern Magnolia,Magnolia grandiflora

Sharing Your DataSharing Your Data

Find this BioLab on theGlencoe Science Web

Site at www.glencoe.com/sec/science andpost your findings in the table provided.Using your findings and information postedby other students, prepare a dichotomouskey that allows you to identify your fivetrees.

INTERNETINTERNET

1. Coniferophytes are cone-bearing trees, seeds formedon cones, evergreens; antho-phytes are flowering plants,seeds formed within a fruit,usually deciduous.

2. Student answers will vary.The Internet (if used) willprovide information for thedata table.

3. Student answers will vary.Students may select speed ofgrowth, temperature toler-ance, or disease resistance asthe most important qualities.

4. a. Student answers will vary.b.Student answers will vary.

5. a. High summer temperatureand drought tolerance would be important factors.

b.Long periods of droughtduring the summer wouldbe an important factor.

c. Temperature toleranceduring the winter would bean important factor.,

ANALYZE AND CONCLUDEANALYZE AND CONCLUDE

591

Data and ObservationsStudent data tables will vary depending onthe initial trees selected for study.

Researching Trees on the Internet

I magine that you are employed by a city in its department of UrbanPlanning. You have just been handed an assignment by the city

manager. The assignment? Research the type of tree that would bemost suitable for planting along the streets of your community.

INTERNETINTERNET

ProblemUse the Internet to find different

trees that would be suitable for plant-ing in your community.

ObjectivesIn this BioLab, you will:■ Research the characteristics of five

different trees.■ Use the Internet to collect and com-

pare data from other students.

■ Conclude which trees would be mostsuitable for planting in your com-munity.

MaterialsInternet access

Skill HandbookUse the Skill Handbook if you need

additional help with this lab.

PREPARATIONPREPARATION

1. Make a copy of thedata table.

2. Pick five trees that you wish to research.Note: Your teachermay provide you with suggestions ifnecessary.

3. Go to the Glencoe Science WebSite at the address shown in theSharing Your Data box to findlinks to information needed forthis BioLab.

4. Record the information in your data table.

PROCEDUREPROCEDURE

NorthernCatalpa,Catalpaspeciosa

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Californiaredbud,Cercis occidentalis

INTERNETINTERNET

Time AllotmentTwo class periods (if enoughcomputers are available in class)Two hours if done at home

Process Skillsacquire information, analyzeinformation, collect data, defineoperationally, think critically,draw a conclusion, interpret data,apply concepts

Prepare different tree lists inadvance for your students. Thismay help to speed up the initialstudent selection process.

Alternative MaterialsIf Internet resources are notavailable, students can still com-plete this BioLab through con-ventional library research usingbooks and periodicals.

PREPARATIONPREPARATION

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PROCEDUREPROCEDURE

Teaching Strategies■ Suggest to students that they modify thespace allowed in the data table for room toaccommodate information or diagrams. Thecategory marked “Additional Information”could be used to describe the trees’ toler-ance to city pollutants.■ Encourage students to complete thisBioLab at home as a homework assignment

if they have computers with Internet accessavailable there. ■ Limit the selection of conifers to one ortwo trees out of the five selected for study.■ To navigate to the Internet BioLabs,choose the Biology: The Dynamics of Lifeicon at the Glencoe Science Web Site. Clickon the student site icon, then the BioLabsicon.

Resource ManagerResource Manager

BioLab and MiniLab Work-sheets, pp. 99-100 L2

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AssessmentAssessment

Sharing Your DataSharing Your Data

To navigateto the

Internet BioLabs choose theBiology: The Dynamics of Lifeicon at Glencoe’s Web Site.Click on the student site icon,then the BioLabs icon. Makesure student’s keys are trulydichotomous and are logical.

Chapter 21 AssessmentChapter 21 Assessment

SUMMARYSUMMARY

Section 21.1

Section 21.2

Main Ideas■ Plants are multicellular eukaryotes with cuticles

and cells with thick walls containing cellulose.Plants have chlorophyll for photosynthesis andstore food in the form of starch.

■ All plants on Earth probably evolved from fila-mentous green algae that lived in ancientoceans. The first plants to make the move fromwater to land may have been leafless.

■ Adaptations for life on land include a waxy cuti-cle; development of leaves, roots, and stems;development of seeds; and the reduction andprotection of the gametophyte generation.

Vocabularycuticle (p. 575)leaf (p. 577)nonvascular plant

(p. 578)root (p. 577)seed (p. 578)stem (p. 577)vascular plant (p. 578)vascular tissue (p. 578)

Main Ideas■ The plant kingdom includes twelve divisions. ■ Plants in the divisions Anthocerophyta,

Hepatophyta, and Bryophyta are non-seed nonvascular plants.

■ Non-seed vascular plant divisions arePsilophyta, Lycophyta, Sphenophyta,and Pterophyta.

■ Cycadophyta, Ginkophyta,Coniferophyta, Gnetophyta, andAnthophyta are vascular seed plant divisions. Anthophytes produce flowersand protect their seeds in fruits.

Vocabularycone (p. 588)frond (p. 587)Survey of the

Plant Kingdom

CHAPTER 21 ASSESSMENT 593

1. Which of the following organisms has vascu-lar tissues? a. bacteria c. fernsb. algae d. hornworts

2. The plant organ that absorbs water and min-erals from the soil is the ________.a. root c. stemb. leaf d. flower

UNDERSTANDING MAIN IDEASUNDERSTANDING MAIN IDEAS 3. Which of the following characteristics isNOT found in plants?a. eukaryotic cellsb. cellulose cell wallsc. prokaryotic cellsd. waxy cuticle

4. Which of the following is NOT part of aseed?a. haploid cell c. food supplyb. protective coat d. embryo

Adapting toLife on Land

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Main IdeasSummary statements can be used bystudents to review the major con-cepts of the chapter.

Using the VocabularyTo reinforce chapter vocabulary, usethe Content Mastery Booklet andthe activities in the Interactive Tutorfor Biology: The Dynamics of Life onthe Glencoe Science Web Site.www.glencoe.com/sec/science

Chapter 21 AssessmentChapter 21 Assessment

All ChapterAssessment

questions and answers have beenvalidated for accuracy and suitabil-ity by The Princeton Review.

What comes to mind when you hear the wordplant? A vase full of flowers? A fruit and veg-etable garden? An evergreen forest? Althoughthese examples are what most people think of

when they hear the word plant, plants provide uswith much more than bouquets, food, and lumber.Nearly 80 percent of the world’s population relieson medications derived from plants. In fact, just

fewer than 100 plants provide the active ingredi-ents used in the ten dozen or so plant-derived

medicines currently on the market.

For thousands of years, the words plants andmedicines were used synonymously. In the

fifth century A.D., for example, doctors of theByzantine Empire used the autumn crocus toeffectively treat rheumatism and arthritis.Hundreds of years ago, certain groups of NativeNorth Americans used the rhizomes of themayapple as a laxative, a remedy for intestinalworms, and as a topical treatment for warts andother skin growths. The oils from peppermintleaves have long been used to settle an upsetstomach. Lotions containing the thick, syrupyliquid from the succulent plant aloe vera areoften used to relieve the pain associated withminor burns, including sunburn. “Herbal” medi-cines have again begun to play an important rolein so-called modern medicine. One of the“herbal” medicines is aspirin.

Aspirin—The wonder drug Evidence suggeststhat almost 2500 years ago, a Greek physiciannamed Hippocrates used a substance from thebark of a white willow tree to treat minor painsand fever. This substance, which is called salicin,unfortunately upset the stomach. Research in the late 1800s by a chemist at the companyknown in the United States simply as Bayer ledto the discovery of acetylsalicylic acid, or aspirin.Aspirin originally was developed by chemist Felix Hoffmann to relieve the joint discomfort

associated with the condition rheumatism. Its usebecame widespread in the early 1900s, however,when it became possible to synthesize salicylicacid in the laboratory.

New Drugs for Cancer Several drugs proven to fight two types of cancer—Hodgkin’s diseaseand leukemia—have been derived from theMadagascar rosy periwinkle. Drugs producedfrom the needles and bark of the Pacific yewhave been used successfully to treat breast, ovar-ian, lung, and other cancers. Although the inter-est in medicinal plants by consumers, medicalexperts, and pharmaceutical companies is grow-ing, it is estimated that less than 10 percent ofthe 250 000 different flowering plant specieshave been studied for their potential use in thefield of medicine.

592 WHAT IS A PLANT?

ConnectionHealthHealth

Connection Medicines fromPlants

How do you think scientists can best decidewhich plants to examine for potential medicinalproperties?

To find out more about medicines derived from plants,

visit the Glencoe Science Web Site. www.glencoe.com/sec/science

CONNECTION TO BIOLOGYCONNECTION TO BIOLOGY

Madagascar rosy periwinkle

592

Purpose Students will learn that plants arean important source of medica-tions.

Teaching Strategies■ Inform students that many ofthe plants used to produce medi-cines, even over-the-counterdrugs, are poisonous. Stress thatthey should take all medicationsonly as directed on the packageor by their prescribing physician.Make sure students realize thatthey should never attempt to useany plant parts to medicate them-selves. ■ After students have read thisfeature, have each of themresearch five other medicationsthat are derived from plants.Combine the findings to make amaster list. Next to the name ofeach medication, include theplant from which it is derived andhow the medicine is used.Responses might include thepotent analgesic morphine, whichis derived from the opium poppy;the antimalarial drug quinine,which is made by boiling the barkof cinchona trees; the heart stim-ulant digitalis that is made fromthe leaves of foxgloves; and thecancer-fighting drug Taxol,which is made from the needlesand bark of the Pacific yew.

Connection to BiologyIt is much more effective to studyplants that have been used toeffectively treat ailments and dis-eases in order to isolate activeingredients than to try to dis-cover such compounds and mix-tures from “scratch.”

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Connection

1. c2. a3. c4. a

UNDERSTANDING MAIN IDEASUNDERSTANDING MAIN IDEAS

VIDEODISCSTV: Plants, How Plants Are UsedUnit 3, Side 2, 2 min.

Medicine

!9C1=^$Ñ"

VIDEOTAPEMindJogger Videoquizzes

Chapter 21: What is a Plant?Have students work in groups as they playthe videoquiz game to review key chapterconcepts.

Resource ManagerResource Manager

Chapter Assessment, pp. 125-130MindJogger VideoquizzesComputer Test BankBDOL Interactive CD-ROM, Chapter 21

quiz

Chapter 21 AssessmentChapter 21 Assessment

CHAPTER 21 ASSESSMENT 595

21. Explain why biologists think the first plantsto adapt to life on land may have been similarto liverworts?

22. Explain why nonvascular plants cannot growas tall as vascular plants.

23. What adaptations made it possible for plantsto live on land?

24. The largest division is the anthophytes. Whatcharacteristic(s) has made them so successful?

25. What advantage(s) might a seed plants haveover a non-seed plant during a drought?

26. Comparing and Contrasting Compare andcontrast conifers and flowering plants.

27. Observing and Inferring What role mightthe jack pine play in a forest area destroyedby fire?

28. Comparing and Contrasting Both greenalgae and aquatic flowering plants live inwater. Are these organisms similar in anyway? How are they different?

29. Concept Mapping Complete the conceptmap by using the following vocabulary terms: leaves, stems, roots, vascular tissue,vascular plant

THINKING CRITICALLYTHINKING CRITICALLY

APPLYING MAIN IDEASAPPLYING MAIN IDEAS ASSESSING KNOWLEDGE & SKILLSASSESSING KNOWLEDGE & SKILLS

The diagram below illustrates the alternation of generations that is found in all plants.

Interpreting Scientific IllustrationsUse the diagram to answer the followingquestions.1. The sporophyte produces spores by the

process of ________.a. mitosis c. fissionb. meiosis d. fertilization

2. The gametes are produced by the ________.a. sporophytes c. sporesb. gametophytes d. embryo

3. Which of the following would NOT have a haploid or n number of chromosomes?a. gametophyte. c. sporophyte.b. spores. d. gametes.

4. Predicting The sporophyte of corn has 20 chromosomes. How many chromosomes would you expect to find in the corn gametes? Explain your answer.

Contains

1.

which is found in

2.

4.

3. 5.

GAMETOPHYTE (n)

Spores (n)

Meiosis

SPOROPHYTE (2n)

Mitosis

Fertilization

Femalegamete (n)

Malegamete (n)

For additional review, use the assessmentoptions for this chapter found on the Biology: TheDynamics of Life Interactive CD-ROM and on theGlencoe Science Web Site.www.glencoe.com/sec/science

CD-ROM

595

22. Nonvascular plants lack the vas-cular tissue that provides sup-port.

23. Adaptations include cuticle, vas-cular tissue, root and stemstructure.

24. They produce flowers and aseed protected by a fruit.

25. Seeds are more resistant to dry-ing out, and seed-producingplants do not need water forreproduction.

26. Conifers and flowering plantsare vascular, seed-producingplants. Flowering plants, unlikeconifers, produce flowers andhave seeds enclosed in a fruit.

27. Because it is possible for thecones to survive a fire, the jackpine could be the first plant tostart growing after the fire.

28. Both the algae and aquaticflowering plant live in water,use the same type of chloro-phyll, and have cellulose cellwalls. However, the aquaticplant has a cuticle and producesseeds and fruits.

29. 1. Vascular plant; 2. Vascular tis-sue; 3. Roots; 4. Stems; 5. Leaves

THINKING CRITICALLYTHINKING CRITICALLY

Chapter 21 AssessmentChapter 21 AssessmentChapter 21 AssessmentChapter 21 Assessment

5. The plant in the photo is a member of thedivision ________.

a. Anthocerophyta c. Lycophytab. Coniferophyta d. Anthophyta

6. Plants and green algae share all of these traits EXCEPT ________.a. reproduce by fissionb. cellulose cell wallsc. store food as starchd. same kind of chlorophyll

7. All plant life cycles include the production of ________.a. seeds c. rootsb. spores d. flowers

8. Which nonplant group is most likely to beancestral to land plants?a. cyanobacteria c. archaebacteriab. bryophytes d. green algae

9. Which of the following adaptations was critical for plants to adapt to life in drierareas?a. production of sporesb. loss of cuticlec. vascular tissue

d. alternation of generations10. Seeds enclosed in a fruit are adaptations of

________.a. Anthophytes c. Coniferophytesb. Bryophytes d. Pterophytes

11. The waxy covering of a leaf is called a(n)________.

12. The sporophyte generation produces________ by the process of ________.

13. Nonvascular plants use ________ and ________ to transport water and nutrients.

14. Conifers produce seeds in a(n) ________,whereas flowering plants produce seedsencased in a(n) ________.

15. Tissues composed of tubelike cells that transport water, food, and other materialsthrough a plant are called ________.

16. The ________ of a plant anchors the plant,whereas the ________ provides support forupright growth.

17. Living in a(n) ________ environment is necessary for reproduction of non-seedplants.

18. The cells of the sporophyte generation are all ________.

19. The cells of the gametophyte generation areall ________.

20. What is the leafy structure of a fern shownbelow?

594 CHAPTER 21 ASSESSMENT

TEST–TAKING TIPTEST–TAKING TIP

Use Process of Elimination On any multiple-choice test, you can use a processof elimination to eliminate any answers that you know are wrong. There are generally morewrong answers than right answers for any givenquestion. Find the ones you know are wrong,eliminate them, and you’ll have fewer choicesfrom which to pick.

594

5. d6. a7. b8. d9. c

10. a11. cuticle12. spores/meiosis13. osmosis/diffusion14. cones/fruit15. vascular tissues16. root/stem17. moist18. diploid or 2n19. haploid or n20. a frond

21. Studies comparing the bio-chemistry of different plantssuggests that the earliest plantswere biochemically most similarto liverworts. Also, many of thefirst plants to appear duringsuccession are often liverworts.The adaptations that allow forsurvival on barren land environ-ment may be the same adapta-tions that allowed for survivalfrom water to a land environ-ment.

APPLYING MAIN IDEASAPPLYING MAIN IDEAS

Chapter 21 AssessmentChapter 21 Assessment

1. b2. b3. c4. 10. Gametes are formed

by meiosis that reducesthe number of chromo-somes by one-half.