Chapter 29 - Plant Diversity I

Question 1

The structural integrity of bacteria is to peptidoglycan as the structural integrity of plant spores is to

A) lignin.
B) cellulose.
C) secondary compounds.
D) sporopollenin.

Answer 1

D) sporopollenin.

Question 2

All of the following are common to both charophytes and land plants except:

A) sporopollenin.
B) lignin.
C) chlorophyll a.
D) cellulose.
E) chlorophyll b.

Answer 2

B) lignin.

Question 3

In animal cells and in the meristem cells of land plants, the nuclear envelope disintegrates during mitosis. This disintegration does not occur in the cells of most protists and fungi. According to our current knowledge of plant evolution, which group of organisms should feature mitosis most similar to that of land plants?

A) unicellular green algae
B) cyanobacteria
C) charophytes
D) red algae
E) multicellular green algae

Answer 3

C) charophytes

Question 4

On a field trip, a student in a marine biology class collects an organism that has differentiated organs, cell walls of cellulose, and chloroplasts with chlorophyll a. Based on this description, the organism could be a brown alga, a red alga, a green alga, a charophyte recently washed into the ocean from a freshwater or brackish water source, or a land plant washed into the ocean. The presence of which of the following features would definitively identify this organism as a land plant?

A) alternation of generations
B) sporopollenin
C) rings of cellulose-synthesizing complexes
D) flagellated sperm
E) embryos

Answer 4

E) embryos

Question 5

Some green algae exhibit alternation of generations. All land plants exhibit alternation of generations. No charophytes exhibit alternation of generations. Keeping in mind the recent evidence from molecular systematics, the correct interpretation of these observations is that

A) charophytes are not related to either green algae or land plants.
B) plants evolved alternation of generations independently of green algae.
C) alternation of generations cannot be beneficial to charophytes.
D) land plants evolved directly from the green algae that perform alternation of generations.
E) scientists have no evidence to indicate whether or not land plants evolved from any kind of alga.

Answer 5

B) plants evolved alternation of generations independently of green algae.

Question 6

Which taxon is essentially equivalent to the “embryophytes”?

A) Viridiplantae
B) Plantae
C) Pterophyta
D) Bryophyta
E) Charophycea

Answer 6

B) Plantae

Question 7

A student encounters a pondweed which, judging from its appearance, seems to be a charophyte. She brings a sample back to her biology lab. Using only a compound light microscope to study the sample, which of the following features should help her to determine whether the sample comes from a charophyte or from some other type of green alga?

1. molecular structure of enzymes inside peroxisomes
2. structure of sperm cells
3. presence of phragmoplasts
4. rings of cellulose-synthesizing complexes

A) 1 and 3
B) 1 and 4
C) 2 and 3
D) 1, 3, and 4
E) 2, 3, and 4

Answer 7

E) 2, 3, and 4

Question 8

Given its composition and location, the phragmoplast should be directly involved in the

A) segregation of daughter chromosomes during anaphase.
B) poleward migration of centrosomes during prophase.
C) synthesis of sporopollenin during G1 and G2 phases.
D) construction of the cell plate during cytokinesis.
E) reinforcement of the nuclear envelope during S phase.

Answer 8

D) construction of the cell plate during cytokinesis.

Question 9

Structurally, phragmoplasts should be most similar to
A) the nuclear lamina.

B) the myofilaments of muscle cells.
C) the internal support structures of microvilli.
D) the cytoskeletal elements that produce cytoplasmic streaming and amoeboid motion.
E) spindle fibers.

Answer 9

E) spindle fibers.

Question 10

What is true of charophytes?

A) They are the ancestors of green algae.
B) They are examples of seedless vascular plants.
C) They are the closest living algal relatives of land plants.
D) They share some features in common with land plants, namely spores surrounded by sporopollenin and alternation of generations.

Answer 10

C) They are the closest living algal relatives of land plants.

Question 11

The functional role of sporopollenin is primarily to

A) comprise spore surface structures that catch the wind and assist in spore dispersal.
B) reduce dehydration.
C) make spores less dense and able to disperse more readily.
D) repel toxic chemicals.
E) provide nutrients to spores.

Answer 11

B) reduce dehydration.

Question 12

If the kingdom Plantae is someday expanded to include the charophytes, then the shared derived characteristics of the kingdom will include

1. rings of cellulose-synthesizing complexes.
2. chlorophylls a and b.
3. alternation of generations.
4. cell walls of cellulose.
5. ability to synthesize sporopollenin.

A) 1 and 5
B) 1, 2, and 3
C) 1, 3, and 5
D) 1, 4, and 5
E) 1, 2, 4, and 5

Answer 12

A) 1 and 5

Question 13

Which of the following were probably factors that permitted early plants to successfully colonize land?

1. the relative number of potential predators (herbivores)
2. the relative number of competitors
3. the relative availability of symbiotic partners
4. air’s relative lack of support, compared to water’s support

A) 1 and 2
B) 2 and 3
C) 3 and 4
D) 1, 2, and 3
E) 1, 2, and 4

Answer 13

D) 1, 2, and 3

Question 14

Which of the following was not a challenge for survival of the first land plants?

A) sources of water
B) sperm transfer
C) desiccation
D) animal predation
E) absorbing enough light

Answer 14

D) animal predation

Question 15

The following are all adaptations to life on land except

A) rings of cellulose-synthesizing complexes.
B) cuticles.
C) tracheids.
D) reduced gametophyte generation.
E) seeds.

Answer 15

A) rings of cellulose-synthesizing complexes.

Question 16

Mitotic activity by the apical meristem of a root makes which of the following more possible?

A) increase of the aboveground stem.
B) decreased absorption of mineral nutrients.
C) increased absorption of CO2.
D) increased number of chloroplasts in roots.
E) effective lateral growth of the stem.

Answer 16

A) increase of the aboveground stem.

Question 17

Which of the following statements is true of archegonia?

A) They are the sites where male gametes are produced.
B) They may temporarily contain sporophyte embryos.
C) They are the same as sporangia.
D) They are the ancestral versions of animal gonads.
E) They are asexual reproductive structures.

Answer 17

B) They may temporarily contain sporophyte embryos.

Question 18

Which of the following is a true statement about plant reproduction?

A) Embryophytes are small because they are in an early developmental stage.
B) Both male and female bryophytes produce gametangia.
C) Gametangia protect gametes from excess water.
D) Eggs and sperm of bryophytes swim toward one another.
E) Bryophytes are limited to asexual reproduction.

Answer 18

B) Both male and female bryophytes produce gametangia.

Question 19

Assuming that they all belong to the same plant, arrange the following structures from largest to smallest.

1. antheridia
2. gametes
3. gametophytes
4. gametangia

A) 1, 4, 3, 2
B) 3, 1, 2, 4
C) 3, 4, 2, 1
D) 3, 4, 1, 2
E) 4, 3, 1, 2

Answer 19

D) 3, 4, 1, 2

Question 20

The leaflike appendages of moss gametophytes may be one to two cell layers thick. Consequently, which of the following is least likely to be found associated with such appendages?

A) cuticle
B) rings of cellulose-synthesizing complexes
C) stomata
D) peroxisomes
E) phenolics

Answer 20

C) stomata

Question 21

Considering that the mature sporophytes of true mosses get their nutrition from the gametophytes on which they grow, and considering these generations as individual plants, what is true of the relationship between true moss sporophytes and gametophytes?

A) Sporophytes are endosymbionts of gametophytes.
B) Sporophytes are mutualists of gametophytes.
C) Sporophytes are commensalists of gametophytes.
D) Sporophytes are parasites of gametophytes.

Answer 21

D) Sporophytes are parasites of gametophytes.

Question 22

As is true of the gametophytes of all land plants, the gametophytes of true mosses lack stomata. Yet, the feather moss Pleurozium harbors nitrogen-fixing cyanobacteria. Which of the following is a feature of moss gametophytes that is most important for the continued survival of these cyanobacteria in the tissues of the feather moss gametophyte?

A) lack of cuticle
B) lack of vascular tissues
C) lack of true leaves or roots
D) lack of an independent sporophyte
E) lack of multiple cell layers in "leaves" of "buds"

Answer 22

E) lack of multiple cell layers in “leaves” of “buds”

Question 23

Which of the following is true of the life cycle of mosses?

A) The haploid generation grows on the sporophyte generation.
B) Spores are primarily distributed by water currents.
C) Antheridia and archegonia are produced by gametophytes.
D) The sporophyte generation is dominant.
E) The growing embryo gives rise to the gametophyte.

Answer 23

C) Antheridia and archegonia are produced by gametophytes.

Question 24

Beginning with the germination of a moss spore, what is the sequence of structures that develop after germination?

1. embryo
2. gametes
3. sporophyte
4. protonema
5. gametophore

A) 4 →1 → 3 → 5 → 2
B) 4 → 3 → 5 → 2 → 1
C) 4 → 5 → 2 → 1 → 3
D) 3 → 4 → 5 → 2 → 1
E) 3 → 1 → 4 → 5 → 2

Answer 24

C) 4 → 5 → 2 → 1 → 3

Question 25

At some time during their existence, bryophytes may feature

A) microphylls.
B) true roots.
C) true leaves.
D) sporangia.
E) umbilical cells.

Answer 25

D) sporangia.

Question 26

Two small, poorly drained lakes lie close to each other in a northern forest. The basins of both lakes are composed of the same geologic substratum. One lake is surrounded by a dense Sphagnum mat; the other is not. Compared to the pond with Sphagnum, the pond lacking the moss mat should have

A) lower numbers of bacteria.
B) reduced rates of decomposition.
C) reduced oxygen content.
D) less-acidic water.

Answer 26

D) less-acidic water.

Question 27

If you are looking for structures that transfer water and nutrients from a bryophyte gametophyte to a bryophyte sporophyte, then on which part of the sporophyte should you focus your attention?

A) spores
B) seta
C) foot
D) sporangium
E) peristome

Answer 27

C) foot

Question 28

In which of the following taxa does the mature sporophyte depend completely on the gametophyte for nutrition?

A) Pterophyta
B) Bryophyta
C) horsetail (Equisetum)
D) Pterophyta, Bryophyta, and horsetail (Equisetum)
E) Pterophyta and Bryophyta

Answer 28

B) Bryophyta

Question 29

You are hiking in a forest and happen upon a plant featuring a central stemlike structure from which sprout many, tiny, leaflike structures. Which of the following would be the most certain means of distinguishing whether it was a true moss or a club moss?

A) its color
B) its height
C) if seeds are present
D) if conducting tissues are present
E) the appearance of its spore-producing structures

Answer 29

E) the appearance of its spore-producing structures

Question 30

Which of the following characteristics helped seedless plants better adapt to life on land?

A) a dominant gametophyte
B) photosystem II
C) a chitinous cuticle
D) stomata on leaves
E) an unbranched sporophyte

Answer 30

D) stomata on leaves

Question 31

A botanist discovers a new species of plant in a tropical rain forest. After observing its anatomy and life cycle, he notes the following characteristics: flagellated sperm, xylem with tracheids, separate gametophyte and sporophyte generations with the sporophyte dominant, and no seeds. This plant is probably most closely related to

A) mosses.
B) charophytes.
C) ferns.
D) gymnosperms.
E) flowering plants.

Answer 31

C) ferns.

Question 32

You are hiking in a forest and come upon a mysterious plant, which you determine is either a lycophyte sporophyte or a pterophyte sporophyte. Which of the following would be most helpful in determining the correct classification of the plant?

A) whether or not it has true leaves
B) whether it has microphylls or megaphylls
C) whether or not it has seeds
D) its height
E) whether or not it has chlorophyll a

Answer 32

B) whether it has microphylls or megaphylls

Question 33

Sporophylls can be found in which of the following?

A) mosses
B) liverworts
C) hornworts
D) pterophytes
E) charophytes

Answer 33

D) pterophytes

Question 34

If a fern gametophyte is a hermaphrodite (that is, has both male and female gametangia on the same plant), then it

A) belongs to a species that is homosporous.
B) must be diploid.
C) has lost the need for a sporophyte generation.
D) has antheridia and archegonia combined into a single sex organ.
E) is actually not a fern, because fern gametophytes are always either male or female.

Answer 34

A) belongs to a species that is homosporous.

Question 35

Assuming that they all belong to the same plant, arrange the following structures from largest to smallest (or from most inclusive to least inclusive).

1. spores
2. sporophylls
3. sporophytes
4. sporangia

A) 2, 4, 3, 1
B) 2, 3, 4, 1
C) 3, 1, 4, 2
D) 3, 4, 2, 1
E) 3, 2, 4, 1

Answer 35

E) 3, 2, 4, 1

Question 36

Which of the following is true of seedless vascular plants?

A) Extant seedless vascular plants are larger than the extinct varieties.
B) Whole forests were dominated by large, seedless vascular plants during the Carboniferous period.
C) They produce many spores, which are really the same as seeds.
D) The gametophyte is the dominant generation.
E) Sphagnum is an economically and ecologically important example.

Answer 36

B) Whole forests were dominated by large, seedless vascular plants during the Carboniferous period.

Question 37

Which of the following are land plants that use the same means of getting sperm to egg that algae use?

A) true mosses, hornworts, and liverworts
B) ferns, whisk ferns, and horsetails
C) all land plants
D) Two of the responses above are correct.

Answer 37

D) Two of the responses above are correct.

Question 38

Arrange the following terms from most inclusive to least inclusive.

1. embryophytes
2. green plants
3. seedless vascular plants
4. ferns
5. tracheophytes

A) 1, 2, 5, 3, 4
B) 2, 1, 5, 3, 4
C) 2, 5, 1, 3, 4
D) 1, 4, 2, 5, 3
E) 2, 1, 5, 4, 3

Answer 38

B) 2, 1, 5, 3, 4

Question 39

Evidence indicates that plants increase the number of stomata in their leaves as atmospheric CO2 levels decline. Increasing the number of stomata per unit surface area should have the effect of doing which of the following?

1. increasing dehydration of leaf tissues
2. decreasing dehydration of leaf tissues
3. countering the effect of declining CO2 on photosynthesis
4. reinforcing the effect of declining CO2 on photosynthesis
5. decreasing the O2 content of air next to the leaves lower than it would otherwise be
6. increasing the O2 content of air next to the leaves higher than it would otherwise be

A) 1, 3, and 5
B) 1, 3, and 6
C) 1, 4, and 5
D) 2, 3, and 6
E) 2, 4, and 5

Answer 39

B) 1, 3, and 6

Question 40

Increasing the number of stomata per unit surface area of a leaf when atmospheric CO2 levels decline is most analogous to a human

A) breathing faster as atmospheric CO2 levels increase.
B) putting more red blood corpuscles (RBCs) into circulation when atmospheric O2 levels decline.
C) removing RBCs from circulation when atmospheric O2 levels increase.
D) breathing more slowly as atmospheric O2 levels increase.

Answer 40

B) putting more red blood corpuscles (RBCs) into circulation when atmospheric O2 levels decline.

Question 41

Which of the following should have had gene sequences most similar to the charophyte that was the common ancestor of the land plants?

A) early angiosperms
B) early bryophytes
C) early gymnosperms
D) early lycophytes
E) early pterophytes

Answer 41

B) early bryophytes

Question 42

Of the following list, flagellated (swimming) sperm are generally present in which groups?

1. Lycophyta
2. Bryophyta
3. Angiosperms
4. Chlorophyta
5. Pterophyta

A) 1, 2, and 3
B) 1, 2, 4, and 5
C) 1, 3, 4, and 5
D) 2, 3, and 5
E) 2, 3, 4, and 5

Answer 42

B) 1, 2, 4, and 5

Question 43

If you were faced with the choice of eliminating all mutualistic symbioses involving plants and other organisms (besides humans), with the goal being to preserve the most plant biomass, which of the following would you save from elimination?

A) the dispersal of seeds in or on animals
B) the dispersal of male gametophytes by animals
C) plants harboring nitrogen-fixing bacteria
D) associations between soil fungi and roots or rhizoids

Answer 43

D) associations between soil fungi and roots or rhizoids

Question 44

During glacial periods in the early evolution of land plants, which of the following would have been a beneficial adaptation regarding the number of stomata per unit surface area, and what accounts for it?

A) increased numbers of stomata, to maximize absorption of increasing levels of atmospheric CO2
B) increased numbers of stomata, to maximize ability to absorb low levels of atmospheric CO2
C) decreased numbers of stomata, to retain CO2 produced by the chloroplasts
D) decreased numbers of stomata, to maximize absorption of low levels of atmospheric CO2

Answer 44

B) increased numbers of stomata, to maximize ability to absorb low levels of atmospheric CO2