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Plants are multicellular, photosynthetic organisms adaptedto a land existence. Among the various adaptations, allplants protect the developing embryo from drying out. Plantshave an alternation of generations life cycle, but somehave a dominant gametophyte (haploid generation) andothers have a dominant sporophyte (diploid generation).

Vascular plants have vascular tissue, that is, xylemand phloem. In the life cycle of vascular plants, the sporo-phyte is dominant.

The nonvascular plants, which include the liver-worts and the mosses, lack true roots, stems, and leaves.In the moss life cycle, spores disperse the species, the ga-metophyte is dominant, and external moisture is requiredfor flagellated sperm to swim to the egg.

Whisk ferns, club mosses, horsetails, and ferns arethe seedless vascular plants that were prominent in swampforests during the Carboniferous period. In the life cycleof seedless plants, spores disperse the species, and the sep-arate gametophyte produces flagellated sperm. Vegeta-tive (asexual) reproduction is used to a degree to disperseferns in dry habitats.

Seed plants have a life cycle in which there are mi-crogametophytes (male gametophytes) and megagame-tophytes (female gametophytes). The microgametophyteis the pollen grain, which produces nonflagellated sperm,and the megagametophyte, which is located within anovule, produces an egg. The pollen grain replaces theflagellated sperm of seedless vascular plants.

Gymnosperms produce seeds that are uncovered.In gymnosperms the microgametophytes develop in pollencones. The megagametophyte develops within an ovulelocated on the scales of seed cones. Following pollina-tion and fertilization, the ovule becomes a winged seedthat is dispersed by wind.

Angiosperms produce seeds that are covered byfruits. The petals of flowers attract pollinators, and theovary develops into a fruit, which aids the dispersal of seeds.Angiosperms provide most of the food that sustains ter-restrial animals, and they are the source of many productsused by humans. Table 29.1 is an adaptation summary.

29PLANTS

CHAPTER REVIEW

STUDY EXERCISES

Study the text section by section as you answer the questions that follow.

• Plants, unlike algae, protect the embryo. This is an adaptation that facilitates a land existence.• The presence of vascular tissue and reproductive strategy are used to compare plants.

1. Indicate whether the following statements about plants are true (T) or false (F):a. adapted to living on landb. diploid sporophyte produces diploid sporesc. haploid gametophyte, which produces sex cellsd. photosynthetic organisms

2. Match the plants to the following plant categories (the categories can be used more than once):1 nonvascular plants 2 seedless vascular plants3 gymnosperms 4 angiosperms

a. club mossesb. conifersc. mossesd. division Magnoliophytae. fernsf. cycads

29.1 CHARACTERISTICS PLANTS (P. 600)

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• The nonvascular plants, which are low-growing, lack a means of water transport and internal support.

3. Label this diagram of part of a moss life cycle with the following terms: antheridium, archegonium, egg, andsperm.

29.2 NONVASCULAR PLANTS (P. 602)

4. In the diagram in question 3, the antheridium and archegonium are part of what

generation? a.____________________

Do mosses have flagellated sperm? b.____________________

Do mosses protect the zygote? c.____________________

5. Is the sporophyte generation dependent on the gametophyte generation in the moss? a.____________________

Do either of these generations have vascular tissue? b.____________________ The capsule contains the

sporangium where the cellular process of c.____________________ occurs during the production

of d.____________________. The latter disperse the species. When they germinate,

a(n) e.____________________ forms to begin the f.____________________ generation.

6. The a.____________________ anchor the moss gametophyte plant in the soil while absorbing minerals and

water. There must be an external source of b.____________________ for the sperm to move from

the c.____________________ to the eggs found in the d.____________________.

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7. Label this diagram of part of the moss life cycle with the following terms: capsule, gametophyte generation,rhizoids, and sporophyte generation.

8. In all vascular plants, the a.____________________ generation is the dominant generation, and it

is b.____________________ (haploid/diploid). c.____________________ vascular tissue conducts water and

minerals up from the soil. d.____________________ vascular tissue transports organic nutrients from one part

of the body to another. An advantage of a diploid plant is that a functional gene can e.____________________ a

faulty gene.9. Indicate whether the statements that follow are true (T) or false (F). Rewrite the false statement(s) to be true.

a. All vascular plants produce pollen grains and seeds. Rewrite:

b. Spores disperse seedless vascular plants, while seeds disperse seed plants. Rewrite:

c. In all vascular plants, the gametophyte generation is dependent on the sporophyte. Rewrite:

10. Indicate whether the following descriptions of rhyniophytes are true (T) or false (F):a. had true stem, roots, and leavesb. spores were produced without benefit of sporangiac. had a forked stem, no roots or leaves

29.3 SEEDLESS VASCULAR PLANTS (P. 604)

• Vascular plants have a system that not only transports water but also provieds internal support.• In nonseed plants, spores disperse the species, and in seed plants, seeds disperse the species.

248

b.

a.

c.

d.

13. In the diagram in question 12, this entire structure is called the a.____________________. This structure has

a(n) b.____________________ shape and represents the c.____________________ generation.

It d.____________________ (does/does not) have vascular tissue and e.____________________ (does/does not)

have flagellated sperm. The sporophyte f.____________________ (is/is not) the dominant

generation. g.____________________ disperse the species.14. Label this diagram of part of the life cycle of a fern with the following terms: fiddlehead, frond, rhizome, and

sorus.

c.

a.

b.

11. Match the descriptions to the following plants:1 whisk ferns 2 club mosses3 horsetails 4 ferns

a. Scalelike leaves cover stems and branches; there are terminal strobili._____ b. Whorls of slender branches form at the nodes of the stem, where the leaves are; they are sometimes

called scouring rushes.c. These plants, alive today, best resemble Rhynia.d. Large fronds subdivide into leaflets.

12. Label this diagram of part of the fern life cycle with the following terms: antheridium, archegonium, and rhizoid.

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15. The frond is part of the a.____________________ generation in the fern, and it b.____________________

(does/does not) have vascular tissue. This generation is c.____________________ (diploid/haploid).16. Label the following as a bryophyte (B) or fern (F):

a. peat mossb. ornamentalc. Native Americans used this during childbirth

• In seed plants, a germinating pollen grain transports sperm to the egg.

17. Label the following diagram, showing the alternation of generations in seed plants with the notation n or 2n:

29.4 SEED PLANTS (P. 608)

18. Is the gametophyte generation dependent on the sporophyte generation in seed plants?a.____________________ Does the sporophyte generation have vascular tissue? b.____________________ What

structure in seed plants replaces flagellated sperm in nonseed plants? c.____________________ What structure

disperses the species in seed plants? d.____________________19. Match the descriptions with the following types of gymnosperms:

1 conifer2 cycad3 ginkgo

a. stout, unbranched stem with large, compound leavesb. fan-shaped leaves shed in autumn; planted in parksc. pine trees, hemlocks, spruces

250

20. Study this diagram of the life cycle of a pine tree and then describe the numbered events.

seed1

2

3

4

7

6

5

meiosisfertilization

zygote

wing

seed:stored foodseed coatembryo

sporophyte

diploid (2n)

haploid (n)

microsporangium

microsporocyte

cross sectionof sporophyll

pollencones

ovule

seed cone

ovule:megasporangiummegasporocyteintegument

cross section ofseed cone scale

pollen tube

archegonium

megagametophyte

microgametophyte(pollen grain)

sperm

micro-gametophyte

integument

pollination

microspores

megaspores

(1) ______________________________________________________________________________________________

______________________________________________________________________________________________

(2) ______________________________________________________________________________________________

______________________________________________________________________________________________

(3) ______________________________________________________________________________________________

______________________________________________________________________________________________

(4) ______________________________________________________________________________________________

______________________________________________________________________________________________

(5) ______________________________________________________________________________________________

______________________________________________________________________________________________

(6) ______________________________________________________________________________________________

______________________________________________________________________________________________

(7) ______________________________________________________________________________________________

______________________________________________________________________________________________

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21. Gymnosperms have an alternation of generations life cycle. Which structure in the diagram in question 20 isdescribed in each of the following?

is the sporophyte a.____________________

produces the microspore b.____________________

produces the megaspore c.____________________

is the microgametophyte d.____________________

contains the megagametophyte e.____________________

contains the sperm f.____________________

contains the egg g.____________________

contains the embryonic sporophyte h.____________________

Angiosperms (p. 612)

22. Label each of the following statements as describing either a monocot (M) or a dicot (D):a. almost always herbaceousb. either woody or herbaceousc. flower parts in fours or fivesd. flower parts in threese. net-veined leavesf. parallel-veined leavesg. vascular bundles arranged in a circle in the stemh. vascular bundles scattered in the stem

23. Label this diagram of the structures of a flower with the following terms: anther, ovary, and ovule.

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Seed:

seeds(mature ovules)

Stamen: Pistil (carpel):

Ovule:

megasporangium

megasporocyte

integument

crosssectionof ovary

stigmastyleovaryovule

filament

anther

endosperm (3n)

embryo

seed coat

polarnuclei

Double fertilization:one sperm unites with polar nucleione sperm unites with egg

spermtube cell

generativecell

mitosis

megaspore

degeneratingmegaspores

mitosis

polar nuclei

maturemicrogametophyte

spermpollen tube

pollen tubeegg

fruit(mature ovary)

egg

megagametophyte(embryo sac)

microspores

pollen sac

cross sectionof anther

diploid (2n)

mature sporophyte

haploid (n)

microgametophyte(pollen grain)

pollination

microsporocyte

fertilization meiosis

antipodals

synergids

1

5

4

3

2

6

24. Study this diagram of the life cycle of a flowering plant and then describe the numbered events.

253

(1) ______________________________________________________________________________________________

______________________________________________________________________________________________

(2) ______________________________________________________________________________________________

______________________________________________________________________________________________

(3) ______________________________________________________________________________________________

______________________________________________________________________________________________

(4) ______________________________________________________________________________________________

______________________________________________________________________________________________

(5) ______________________________________________________________________________________________

______________________________________________________________________________________________

(6) ______________________________________________________________________________________________

______________________________________________________________________________________________25. Flowering plants have an alternation of generations life cycle. Which structure in the diagram in question 24

is described in each of the following?

is the sporophyte a.____________________

produces the microspore b.____________________

produces the megaspore c.____________________

is the microgametophyte d.____________________

contains the megagametophyte e.____________________

contains the sperm f.____________________

contains the egg g.____________________

contains the embryonic sporophyte h.____________________

matures to become a fruit i.____________________

26. The color and arrangement of flower parts are designed to a.______________________________________________.

A flower, which is necessary to the reproduction of flowering plants, contains b.____________________________

_________________________________________________________________________________________________.

A flower produces seeds enclosed by c.____________________, which helps d.____________________.

27. Complete the following table to compare the different plants:

Plant Vascular Tissue Dominant Generation Spores or Seeds Fruit(yes or no) Disperse Species (yes or no)

mosses

ferns

gymnosperms

angiosperms

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Classification Tiddledywinks

1. Players are given a set of cups of different colors and sizes.a. Sort these cups according to size as quickly as you can. Each different size represents a category in the

classification system.b. Sort the cups according to color as quickly as you can. The different colors represent the different

kingdoms (and the organisms within) of the classification system.

Cupsplants cyanobacteria slime moldprotozoa algae protistsviruses mosses bacteriaflowers nonvascular plants vascular plantsmonera fungi fernpine

2. Players are given disks and required to flip them into the correct cup. A small disk goes into a small cup, and alarge disk goes into a large cup. (More than one disk can go into a cup.)

Disksa. toxinsb. red, brown, golden brown, green, multicoloredc. single cell, motile, food vacuolesd. live on the lande. treesf. vascular tissueg. lack nucleush. protect the embryoi. saprotrophicj. photosynthesisk. alternation of generationsl. haplontic cycle

m. alive?n. malariao. bacteriophagep. Amoeba, Paramecium, Euglenaq. zygospore, sac, club, imperfectr. heterosporess. fruitt. fruiting bodyu. hyphaev. rhizoids, shoot, leafletsw. zoosporesx. naked seedsy. pollen carried by insectsz. endospores

aa. plasmodiumbb. monocot and dicotcc. fronds

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CHAPTER TEST

OBJECTIVE QUESTIONS

Do not refer to the text when taking this test.1. Select the incorrect association.

a. gametophyte—diploid generationb. gametophyte—produces sex cellsc. sporophyte—diploid generationd. sporophyte—produces haploid spores

2. Select the nonvascular plant.a. bryophyteb. cycadc. fernd. rosebush

3. The antheridium is part of thea. megagametophyte.b. megasporophyte.c. microgametophyte.d. microsporophyte.

4. Rhyniophytes are significant because theya. are currently the most successful conifers.b. are currently the most successful flowering

plants.c. were the first to evolve flowers.d. were the first to evolve vascular tissue.

5. Xylem and phloem area. the covering tissues on roots, stems, and leaves.b. the male and female parts of a flower.c. two kinds of flowering plants.d. two types of vascular tissue.

6. Ferns are plants that area. nonvascular with seeds.b. nonvascular without seeds.c. vascular with seeds.d. vascular without seeds.

7. Which structure develops into a pollen grain?a. antheridiumb. archegoniumc. megaspored. microspore

8. Select the characteristic NOT descriptive ofconifers.a. can withstand cold wintersb. can withstand hot summersc. needlelike leavesd. reproduce through flowers

9. Select the incorrect statement about angiosperms.a. contain only tracheids in their vascular tissueb. did not diversify until the Cenozoic erac. include tiny plants living on pond surfacesd. the most successful group of plants

10. Select the incorrect association.a. dicot—woody or herbaceousb. dicot—vascular bundles arranged in a circle

within the stemc. monocot—almost always herbaceousd. monocot—net-veined leaf

11. In comparing alternation of generations for non-seed and seed plants, it is apparent that seedplants havea. flowers only.b. heterospores.c. flagellated sperm.d. megagametophytes and microgametophytes.e. Both b and d are correct.

12. The fern is a nonseed plant anda. is a bryophyte.b. has flagellated sperm.c. lacks vascular tissue.d. All of these are correct.

13. The dominant generation in the seed plants isthea. sporophyte.b. gametophyte.c. green leafy shoot.d. flower only.

14. Ferns are restricted to moist places becausea. of the sporophyte generation called the frond.b. of a sensitive type of chlorophyll.c. of the water-dependent gametophyte

generation.d. they never grow very tall.

15. In the life cycle of seed plants, meiosisa. produces the gametes.b. produces microspores and megaspores.c. does not occur.d. produces spores.

16. Double fertilization refers to the fact that in an-giospermsa. two egg cells are fertilized within an ovule.b. a sperm nucleus fuses with an egg cell and

with polar nuclei.c. two sperm are required for fertilization of one

egg cell.d. a flower can engage in both self-pollination

and cross-pollination.

256

17. Identify the correct order of life cycle stages ina moss.a. gametophyte—sporophyte—spores—zygote—

protonemab. sporophyte—spores—protonema—gametes—

zygotec. g a m e t o p h y t e — s p o r e s — s p o r o p h y t e —

gametes—zygoted. zygote—sporophyte—gametophyte—spores—

protonema18. The sporangia of a fern is generally

a. at the tips of the rhizomes.b. on the bottom surface of the prothallus.c. inside the fiddleheads.d. at the point where leaves join the stem.e. on the undersides of fronds.

19. In which of these groups is the gametophyte nu-tritionally dependent upon the sporophyte?a. fernsb. angiospermsc. gymnospermsd. Both b and c are correct.e. All of these are correct.

20. In pine trees, ______ develop in separate types ofcones.a. microgametophytes and megagametophytesb. pollen and ovulesc. microspores and megasporesd. Both a and b are correct.e. All of these are correct.

THOUGHT QUESTIONS

Answer in complete sentences.21. What do you think will be the impact on human life if there is a major extinction of plants during the next

century?

22. Should algae be considered plants? Offer reasons why they should and should not be classified this way.

Test Results: ______ Number right ÷ 22 = ______ × 100 = ______ %

ANSWER KEY

STUDY EXERCISES

1. a. T b. F c. T d. T 2. a. 2 b. 3 c. 1 d. 4 e. 2f. 3 3. a. antheridium b. egg c. archegoniumd. sperm 4. a. gametophyte b. yes c. yes 5. a. yesb. no c. meiosis d. spores e. protonema f. gameto-phyte 6. a. rhizoids b. water c. antheridia d. archego-nia 7. a. capsule b. sporophyte generationc. gametophyte generation d. rhizoids 8. a. sporo-phyte b. diploid c. Xylem d. Phloem e. mask9. a. F. Only gymnosperms and angiosperms producepollen grains and seeds. b. T c. F. In most seed vascu-lar plants, the gametophyte generation is dependent onthe sporophyte. 10. a. F b. F c. T 11. a. 2 b. 3c. 1 d. 4 12. a. archegonium b. antheridium c. rhi-zoid 13. a. prothallus b. heart c. gametophyte d. doesnot e. does f. is g. Spores 14. a. frond b. sorusc. fiddlehead d. rhizome 15. a. sporophyte b. doesc. diploid 16. a. B b. F c. F 17. a. 2n b. 2n c. 2nd. n e. n f. n g. n h. n i. n j. 2n 18. a. yes b. yesc. pollen grain d. seed 19. a. 2 b. 3 c. 1 20. (1) Sporo-

phyte is dominant. (2) pollen cones and seed cones (3) mi-crosporangia on lower surface of pollen cone; megaspo-rangia on upper surface of seed cone inside ovule(4) Meiosis produces microspores/megaspores. (5) Eachmicrospore develops in a microgametophyte (pollengrain); one megaspore develops into a megagametophyte.(6) Pollen tube delivers sperm to egg. (7) Ovule becomesseed. 21. a. tree b. microsporangium on scale of pollencone c. megasporangium inside ovule on scale of seedcone d. pollen grain e. ovule f. mature microgametophyte(pollen grain) g. megagametophyte inside ovuleh. seed 22. a. M b. D c. D d. M e. D f. M g. D h. M23. a. anther b. ovary c. ovule 24. (1) Flower con-tains stamens and pistil. (2) Megasporocyte producesfour haploid megaspores; microsporocyte produces fourhaploid microspores. (3) One functional megaspore sur-vives and divides mitotically; microgametophyte con-tains generative cell nucleus and tube cell nucleus.(4) Megagametophyte results and consists of eight hap-loid nuclei; pollen grain germinates and produces a pollentube. (5) Double fertilization occurs; one sperm fertil-

257

izes the egg, and the other joins with the polar nuclei.(6) Seed contains endosperm, embryo, and seedcoat. 25. a. flowering plant b. pollen sac c. megas-porangium inside ovule d. pollen grain e. ovule f. pollen

tube g. megagametophyte (embryo sac) h. seed i. ovary26. a. attract pollinators b. micro- and megasporangiawhere microspores and megaspores are produced c. fruitd. disperse the species

27.

Vascular Tissue Dominant Spores or Seeds Fruit(yes or no) Generation Disperse Species (yes or no)

no gametophyte spores no

yes sporophyte spores no

yes sporophyte seeds no

yes sporophyte seeds fruit

CLASSIFICATION

TIDDLEDYWINKS

1. a. Size: largest: kingdoms = monera, protists, plantsnext: groups = bryophytes, vascular plants; next: organ-isms = all the rest b. Colors: 1. monera: bacteria, in-cluding cyanobacteria 2. protists: algae, protozoa, slimemold 3. fungi 4. plants: nonvascular plants (mosses), vas-cular plants (includes all others) 2. a. bacteria b. algaec. protozoa d. plants e. pine, flower f. vascular plantsg. monera h. plants i. fungi j. plants, algae k. plantsl. protists m. viruses n. protozoa o. viruses p. protozoaq. fungi r. pine, flower s. flower t. fungi u. fungiv. mosses w. algae x. pine y. flower z. bacteria aa. slimemold bb. flower cc. fern

CHAPTER TEST

1. a 2. a 3. c 4. d 5. d 6. d 7. d 8. d 9. a10. d 11. e 12. b 13. a 14. c 15. b 16. b17. b 18. e 19. d 20. e 21. The ecologic and eco-nomic contributions of plants will be lost. Examples in-clude loss of food production and inability to maintain abalance of gases in the atmosphere. 22. They are pho-tosynthetic producers, so in this way they should be con-sidered plants. However, they lack the adaptations forterrestrial life, so in this way they should not be consid-ered plants.