Botany 4/4 Quiz

In your opinion, which of the bryophytes has the most highly developed sporophyte? Which has the most highly developed gametophyte? In each case, give the reasons for your answer.

Although several different answers are possible, many botanists would consider the mosses to have the most highly developed sporophytes and gametophytes. Not only do both contain leptoids and hydroids (at least in some members), but the gametophytes produce multicellular rhizoids. In addition, the sporophytes have an elongate seta, and some produce an elaborate peristome.

What evidence is there in support of a charophycean green alga ancestry for plants?

Both charophytes and plants contain chloroplasts with well-developed grana, both have motile cells with flagella that extend from the side of the cell, and both exhibit breakdown of the nuclear envelope at mitosis and persistent spindles or phragmoplasts during cytokinesis.

Bryophytes and vascular plants share a number of characters that distinguish them from charophycean green algae and that adapt them for existence on land. What are those characters?

Bryophytes and vascular plants share a number of characters that distinguish them from the charophytes. These shared characteristics include: (1) the presence of male and female gametangia, called antheridia and archegonia, respectively, with a protective layer called a sterile jacket layer;(2) retention of both the zygote and the developing multicellular embryo, or young sporophyte, within the archegonium or the female gametophyte; (3) the presence of a multicellular diploid sporophyte, which results in an increased number of meioses and an amplification of the number of spores that can be produced following each fertilization event; (4) multicellular sporangia consisting of a sterile jacket layer and internal spore-producing (sporogenous) tissue; (5) meiospores with walls containing sporopollenin, which resists decay and drying; and (6) tissues produced by an apical meristem. Charophytes lack all of these shared bryophyte and vascular plant characters, which are correlated with the existence of plants on land

By means of a simple, labeled diagram, outline a generalized life cycle of a bryophyte. Explain why it is referred to as an alteration of heteromorphic generations

In the bryophytes, the gametophyte usually is larger as well as free-living, and the sporophyte is smaller and permanently attached to, and nutritionally dependent on, its parental gametophyte. By contrast, the sporophyte of vascular plants is larger than the gametophyte and ultimately free-living. In addition, the bryophyte sporophyte is unbranched and bears only a single sporangium, whereas the sporophytes of extant vascular plants are branched and bear many more sporangia (polysporangiophytes). Vascular plant sporophytes therefore produce a great many more spores than do the sporophytes of bryophytes.

What characters shared by vascular plants are lacking in bryophytes?

Living bryophytes lack the water- and food-conducting (vascular) tissues called xylem and phloem, respectively that are present in vascular plants. Although some bryophytes have specialized conducting tissues, the cell walls of the bryophyte water-conducting cells are not lignified, as are those of the vascular plants. Also, there are differences in the life cycles of bryophytes and vascular plants, both of which exhibit alternating heteromorphic gametophytic and sporophytic generations. In the bryophytes, the gametophyte usually is larger as well as free-living, and the sporophyte is smaller and permanently attached to, and nutritionally dependent on, its parental gametophyte. By contrast, the sporophyte of vascular plants is larger than the gametophyte and ultimately free-living. In addition, the bryophyte sporophyte is unbranched and bears only a single sporangium, whereas the sporophytes of extant vascular plants are branched and bear many more sporangia (polysporangiophytes). Vascular plant sporophytes therefore produce a great many more spores than do the sporophytes of bryophytes.

Cooksonia a member of the phylum ______, is the oldest known ______.

Rhyniophyta; vascular plant

Describe the structural modifications related to water absorption in Sphagnum. Why is Sphagnum of such great ecological importance?

Sphagnum leaves contain large, dead cells that are perforated so that they readily become filled with water. Sphagnum is ecologically important because the peat they form constitutes large amounts of stored organic carbon that is not readily decayed to carbon dioxide by microorganisms. Ecologists are concerned that global warming brought about by increasing amounts of carbon dioxide and other gases in the atmosphere--due in large part to human activities--might result in oxidation of peatland carbon. This could further increase carbon dioxide levels and global warming.

The evolutionary relatedness between green algae and bryophytes is indicated by the observation that green algae contain ______ plastid(s) per cell and the reproductive cells of many bryophytes contain ______ plastid(s) per cell. a. 1; 1 b. 2; 2 c. 1; 2 d. 2; 1 e. 3; 3

a. 1; 1

Peat mosses belong to the phylum ______, class ______. a. Bryophyta; Sphagnidae b. Bryophyta; Andreaeidae c. Bryophyta; Bryidae d. Marchantophyta; Sphagnidae e. Marchantophyta; Bryidae

a. Bryophyta; Sphagnidae

The two clades of liverworts are the _______ liverworts and the _______ liverworts. a. complex thalloid; leafy liverworts and simple thalloid b. leafy; thalloid c. simple thalloid; leafy liverworts and complex thalloid d. complex leafy; simple leafy liverworts and thalloid e. simple leafy; complex leafy liverworts and thalloid

a. complex thalloid; leafy liverworts and simple thalloid

The ______ is embedded in the archegonium. a. foot b. seta c. capsule d. neck canal e. sporangium

a. foot

Heterospory differs from homospory in that heterospory involves: a. gametophytes with endosporic development. b. larger gametophytes. c. bisexual gametophytes. d. spores differentiated on the basis of size not function. e. different types of spores produced in the same sporangium

a. gametophytes with endosporic development.

The function of elaters is to: a. help disperse spores. b. help disperse gemmae. c. strengthen the spore wall. d. conduct water and nutrients through the plant body. e. support the archegoniophores.

a. help disperse spores.

When the cells of the ________ disintegrate, they form a tube through which sperm move to the egg. a. neck canal b. capsule c. calyptra d. venter e. placenta

a. neck canal

What do ALL steles have in common? a. primary xylem and primary phloem b. a pith c. leaf gaps d. dermal tissue e. vascular and cork cambia

a. primary xylem and primary phloem

Bryophytes share all of the following features with charophytes except: a. the presence of archegonia. b. chloroplasts with well-developed grana. c. flagella that extend from the sides of the cell. d. a nuclear envelope that breaks down during mitosis. e. persistent spindles or phragmoplasts.

a. the presence of archegonia.

The granite mosses belong to the phylum ______, class ______. a. Bryophyta; Sphagnidae b. Bryophyta; Andreaeidae c. Bryophyta; Bryidae d. Hepatophyta; Sphagnidae e. Hepatophyta; Bryidae

b. Bryophyta; Andreaeidae

Which sequence of events most likely describes the evolution of megaphylls? a. Overtopping dichotomous branching, planation, webbing b. Dichotomous branching, overtopping, planation, webbing c. Planation, dichotomous branching, overtopping, webbing d. Webbing, dichotomous branching, overtopping, planation e. Overtopping, planation, webbing, dichotomous branching,

b. Dichotomous branching, overtopping, planation, webbing

______ is a liverwort that carries its gametangia on gametophores. a. Frullania b. Marchantia c. Anthoceros d. Riccia e. Ricciocarpus

b. Marchantia

The genus ______ is characterized by capsules raised on a pseudopodium. a. Andreaea b. Sphagnum c. Polytrichum d. Anthoceros e. Ricciocarpus

b. Sphagnum

Which of the following statements about bryophytes is FALSE? a. They lack xylem and phloem. b. The cell walls of their water-conducting cells are lignified. c. They exhibit alternating heteromorphic generations. d. The sporophyte is usually nutritionally dependent on the gametophyte. e. The gametophyte is usually larger than the sporophyte.

b. The cell walls of their water-conducting cells are lignified.

Which of the following statements about reproduction in vascular plants is FALSE? a. The eggs are nonmotile. b. The gametophyte is structurally more complex than the sporophyte. c. All vascular plants are oogamous. d. There is an alternation of heteromorphic generations. e. The sporophyte is the dominant phase of the life cycle.

b. The gametophyte is structurally more complex than the sporophyte.

Tracheids differ from vessel elements in that tracheids: a. have lignified thickenings. b. are less-specialized cells. c. are a type of tracheary element. d. conduct water and minerals. e. provide support.

b. are less-specialized cells.

Anthoceros is an example of a: a. moss. b. hornwort. c. leafy liverwort. d. thalloid liverwort. e. vascular plant.

b. hornwort.

Matrotrophy refers to the: a. attraction of sperm by the egg. b. nourishment of the zygote by the archegonium. c. transport of sugars through the placenta. d. division of the zygote within the venter. e. movement of sugars through plasmodesmata.

b. nourishment of the zygote by the archegonium.

A major difference between the spore walls of bryophytes and charophytes is that the bryophyte spore walls contain: a. lignin. b. sporopollenin. c. cellulose. d. phenolic materials. e. stomata.

b. sporopollenin.

The protonema of Andreaea consists of ______ of cells. a. a single row b. two or more rows c. a two-layer-thick plate d. a one-layer-thick plate e. two overlapping plates

b. two or more rows

A peristome is a capsular structure characteristic of members of the phylum ______, class ______. a. Bryophyta; Sphagnidae b. Bryophyta; Andreaeidae c. Bryophyta; Bryidae d. Hepatophyta; Sphagnidae e. Hepatophyta; Bryidae

c. Bryophyta; Bryidae

The "true mosses" belong to the phylum ______, class ______. a. Bryophyta; Sphagnidae b. Bryophyta; Andreaeidae c. Bryophyta; Bryidae d. Hepatophyta; Sphagnidae e. Hepatophyta; Bryidae

c. Bryophyta; Bryidae

Which of the following is NOT a group of mosses of phylum Bryophyta? a. Peat mosses b. Granite mosses c. Club mosses d. Bryidae e. Andreaeidae

c. Club mosses

The four major groups of vascular plants are: I. monilophytes lycophytes, and progymnosperms II. flowering plants III. rhyniophytes, zosterophyllophytes, and trimerophytes IV. gymnosperms Which of the following is the correct sequence—from earliest to most recent—of the time period in which they were dominant on Earth? a. I, II, III, IV b. I, III, IV, II c. III, I, IV, II d. III, IV, II, I e. IV, III, I, II,

c. III, I, IV, II

Which of the following statements about primary growth is FALSE? a. It occurs close to the tips of stems and roots. b. It is initiated by the apical meristems. c. It primarily leads to thickening of the plant body. d. It gives rise to primary tissues. e. It gives rise to the primary plant body.

c. It primarily leads to thickening of the plant body.

Which of the following statements about the phylum Rhyniophyta is FALSE? a. They are the earliest well-known vascular plants. b. They lived during the mid-Silurian. c. They were differentiated into stems roots, and leaves. d. They had dichotomously branching stems. e. They were homosporous.,

c. They were differentiated into stems, roots, and leaves.

Which of the following statements concerning the transport of nutrients from the gametophyte to the embryo is FALSE? a. Transport is apoplastic. b. Transport is facilitated by the placenta. c. Transport occurs via plasmodesmata. d. The archegonium provides sugars to the embryo. e. The archegonium provides amino acids to the embryo.

c. Transport occurs via plasmodesmata.

Members of the phylum ______ probably evolved directly from the rhyniophytes and most likely are the ancestors of the ferns and progymnosperms. a. Pteridophyta b. Lycopodiophyta c. Trimerophytophyta d. Zosterophyllophyta e. Sphenophyta

c. Trimerophytophyta

Embryophytes are characterized by having: a. few mitotic divisions between fertilization and meiosis. b. a multicellular embryo that has stomata. c. a multicellular, matrotrophic embryo. d. a dominant gametophyte generation. e. vascular tissues.

c. a multicellular, matrotrophic embryo.

Microphylls differ from megaphylls in that microphylls: a. occur in most vascular plants. b. are associated with leaf gaps. c. are associated with protosteles. d. have branched veins. e. evolved from branch systems.

c. are associated with protosteles.

In bryophytes, rhizoids usually: a. absorb ions. b. absorb water. c. attach to the substrate d. are unicellular. e. are true roots.

c. attach to the substrate

Most liverworts develop close symbiotic associations with the: a. zygomycetes. b. ascomycetes. c. glomeromycetes. d. chytrids. e. basidiomycetes.

c. glomeromycetes.

Bryophytes are a group of organisms at the transition between: a. brown algae and algae. b. fungi and plants. c. green algae and vascular plants. d. nonvascular and vascular plants. e. aquatic and terrestrial plants.

c. green algae and vascular plants.

In the liverworts, an androecium is a: a. structure producing sperm. b. group of water-conducting cells. c. short side branch bearing antheridia. d. tubular sheath surrounding the archegonium. e. structure of the gemma cup.

c. short side branch bearing antheridia.

In ferns antheridiogens induce antheridia in _______ gametophytes. a. all b. larger, less mature c. smaller, less mature d. larger, more mature e. smaller, more mature,

c. smaller, less mature

Hadrom contains: a. gametes. b. food-conducting cells. c. water-conducting cells. d. spores. e. degenerate nuclei.

c. water-conducting cells.

Which of the following statements about sexual reproduction in bryophytes is FALSE? a. Sperm are the only flagellated cells produced by bryophytes. b. The zygote is matrotrophic. c. Sex is governed by the distribution of sex chromosomes. d. In the antheridium, the spermatogenous cells are "sterile." e. Chemicals released from the archegonium attract sperm.

d. In the antheridium, the spermatogenous cells are "sterile."

Which of the following is NOT an evolutionary trend in the vascular plants? a. Nutritional dependency of the gametophyte on the sporophyte b. Reduction in size of the gametophyte c. Reduction in complexity of the gametophyte d. Increased prominence of antheridia and archegonia e. Decreased reliance on water for transferring sperm to egg

d. Increased prominence of antheridia and archegonia

Which of the following statements concerning hornworts is FALSE? a. Some gametophytes have chloroplasts containing a pyrenoid. b. A meristem develops between the foot and the sporangium. c. The sporophyte contains several layers of photosynthetic cells. d. The sporophyte is covered with a cuticle but lacks stomata. e. The sporophyte dehisces longitudinally.

d. The sporophyte is covered with a cuticle but lacks stomata.

Which of the following statements about bryophytes is FALSE? a. They may be "thalloid" or "leafy." b. Some species contain strands with conducting functions. c. They do not have true stems and leaves. d. They have rhizoids that absorb water and nutrients. e. Some species have plasmodesmata with a desmotubule.

d. They have rhizoids that absorb water and nutrients.

Which of the following statements about stomata is FALSE? a. Each stoma is bordered by two guard cells. b. They aid in the uptake of CO2. c. They generate a flow of water between sporophyte and gametophyte. d. They occur in all bryophytes. e. They are sites of loss of water vapor.

d. They occur in all bryophytes.

The protonema of Sphagnum consists of ______ of cells. a. a single row b. two or more rows c. a two-layer-thick plate d. a one-layer-thick plate e. two overlapping plates

d. a one-layer-thick plate

What is the function of hydroids? a. anchoring the gametophyte b. photosynthesis c. aiding in spore dispersal d. conducting water e. conducting food

d. conducting water

In contrast to the ventral portion, the dorsal portion of a thalloid liverwort: a. contains rhizoids. b. contains scales. c. is thicker. d. contains chlorophyll. e. is colorless.

d. contains chlorophyll.

Which of the following is NOT a characteristic shared by bryophytes and vascular plants? a. multicellular embryos b. a charophycean-alga-like ancestor c. a monophyletic lineage d. dominant gametophytes e. an alternation of heteromorphic generations

d. dominant gametophytes

At maturity, the sporophyte of most bryophytes consists of the: a. foot and seta only. b. seta and capsule only. c. capsule and calyptra only. d. foot, seta, and capsule. e. seta, capsule, and calyptra.

d. foot, seta, and capsule.

A perianth is characteristically found in the: a. thalloid liverworts. b. hornworts. c. mosses. d. leafy liverworts. e. genus Marchantia.

d. leafy liverworts.

After they germinate, bryophyte spores first give rise to: a. hyphae. b. archegonia. c. rhizoids. d. protonema. e. antheridia.

d. protonema.

Which of the following is NOT a characteristic shared by bryophytes and vascular plants? a. multicellular sporangia b. sporopollenin in spore walls c. tissues produced by an apical meristem d. retention of the embryo within an antheridium e. antheridia and archegonia with sterile jacket layers

d. retention of the embryo within an antheridium

The conducting cells of the phloem are called: a. tracheids. b. vessel elements. c. leaf traces. d. sieve elements. e. hydroids.

d. sieve elements.

In Marchantia, the mature capsule contains: a. spores only. b. elaters only. c. gemmae only. d. spores and elaters only. e. spores, elaters, and gemmae.

d. spores and elaters only.

The base of the bryophyte archegonium, called the ______, contains ______. a. placenta; a single egg b. capsule; spermatogenous cells c. calyptra; several eggs d. venter; a single egg e. seta; spermatogenous cells

d. venter; a single egg

Which of the following statements concerning the bryophytes is FALSE? a. Some can grow in Antarctica. b. Some can grow above timberline. c. Some can grow in deserts. d. Some can grow in freshwater. e. Some can grow in high-salinity salt water.

e. Some can grow in high-salinity salt water.

In bryophytes, fertilization takes places in the: a. open water. b. capsule. c. seta. d. antheridium. e. archegonium.

e. archegonium.

Leaves of leafy liverworts differ from those of mosses in that liverwort leaves: a. are of equal size. b. are spirally arranged. c. have a thickened midrib. d. are entire rather than lobed or dissected. e. are arranged in two rows with a third row of smaller leaves.

e. are arranged in two rows with a third row of smaller leaves.

The siphonostele of ferns: a. is the most primitive type of stele. b. consists of a solid core of vascular tissues. c. occurs only in the roots. d. has a series of discrete strands around a central pith. e. has leaf gaps.

e. has leaf gaps.

periderm

e. lateral

Hyaline cells are found in the _____ of ______. a. rhizoids; Sphagnum b. rhizoids; Riccia c. leaves; Andreaea d. leaves; Marchantia e. leaves; Sphagnum

e. leaves; Sphagnum

The ________ is located between the sporophyte and gametophyte generations. a. seta b. capsule c. calyptra d. venter e. placenta

e. placenta

Sporopollenin is found in _____ of the charophytes, in _____ of the bryophytes, and in ____ of the vascular plants. a. spores; spores; spores b. zygotes; zygotes; zygotes c. spores; zygotes; zygotes d. spores; zygotes; spores. e. zygotes; spores; spores

e. zygotes; spores; spores

Antheridiophores and archegoniophores are distinctive features of Riccia and Ricciocarpus.

false

As long as conditions are favorable, the hornwort sporophyte continues to elongate due to the activity of an apical meristem.

false

Both bryophytes and charophytes retain their multicellular embryos within the female gametophyte.

false

Bryophytes differ from charophytes in that bryophytes have asymmetrical motile cells.

false

Bryophytes produce preprophase bands similar to those found in charophycean algae.

false

Gemmae and gemma cups are directly involved in sexual reproduction.

false

Hyaline cells are living cells with ringlike and spiral wall thickenings.

false

In the Bryidae, gametophytes are borne on the sporophytes.

false

Peat mosses normally release hydroxide ions, thereby raising the pH of their environment.

false

The "cushiony" growth habit is characteristic of epiphytic mosses. ["pattern" meant?]

false

When bryophyte spores germinate, they first form juvenile developmental stages called rhizoids.

false

The main tissue systems of the vascular plant are the ______ systems. a. root and shoot b. root

shoot, and reproductive c. root, stem, and leaf d. dermal, vascular, and ground e. xylem, phloem, and ground,d. dermal, vascular, and ground

The Zosterophyllophyta differ from the Rhyniophyta in that the Zosterophyllophyta: a. were homosporous. b. were not differentiated into roots

stems, and leaves. c. had a protostele. d. became extinct. e. produced lateral sporangia.,e. produced lateral sporangia.

In the evolution of vascular plants

there is a trend toward the: a. above-ground parts becoming structurally similar to the below-ground parts. b. progressive reduction of the sporophyte. c. sporophyte becoming nutritionally dependent on the gametophyte. d. increased protection of the gametophyte by the sporophyte. e. production of seeds in all lineages.,d. increased protection of the gametophyte by the sporophyte.

Ambuchanania and Sphagnum are the two genera in the class Sphagnidae.

true

Bryophytes are transitional between the charophycean algae and vascular plants.

true

Bryophytes were the first extant plant group to diverge from a monophyletic plant lineage.

true

Despite a superficial resemblance between their gametophytes, hornworts and thallose liverworts are only distantly related.

true

In bryophytes, sperm must swim through water to reach the egg.

true

Leptoids are somewhat similar to a type of food-conducting cells in vascular plants.

true

Some hornwort species form a symbiotic relationship with nitrogen-fixing bacteria.

true

The protonema of Sphagnum is similar to thallus of Coleochaete.

true

The sporophyte epidermis of mosses contains stomata that resemble the stomata of vascular plants.

true

The sporophyte of Anthoceros lacks a seta.

true

The sporophyte of Riccia is simpler in structure than the sporophyte of Marchantia.

true

The sporophytes of mosses are commonly associated with cyanobacteria.

true

The upper portion of a thalloid liverwort is thinner than the lower portion.

true