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AP Biology Plant Questions From Chapters 29-30, 35-39

STUDY
PLAY
Which of the following plant groups is incorrectly paired with its gametophyte generation
Fern-frond growing from rhizome
Which of the following is most likely the closest relative of the vascular plants
Bryophytes
Which of the following functions may secondary compounds serve
All of the above
Which of the following has been proposed by plant biologists as the deepest branch that establishes the boundary of the plant kingdom
The kingdoms Plantae, Streptophyta, and Viridiplantae
If you could take a time machine back to the Carboniferous period, which of the following scenarios would you most likely encounter
Swampy forests dominated by seedless vascular plants (ferns)
In which of the following groups do sperm no longer have to swim to reach the female gametophyte
Gymnosperms and angiosperms
What provides food for a developing sporophyte embryo in a gymnosperm seed
Female gametophyte tissue
Which of the following is the correct path that a pollen tube takes to reach the female gametophyte in an angiosperm
Stigma, style, ovary, ovule, embryo sac
How many generations are represented in a pine seed
3: seed coat from parent sporophyte, food supply from gametophyte, and sporophyte embryo
Gymnosperms rose to dominance during which of the following periods
Permian
If the angiosperm gametophyte generation has been reduced to so few cells, why hasn't it been eliminated from the life cycle
The gametophyte generation produces both the protective seed coat and nourishment for developing embryo
Which of the following is a key difference between seedless vascular plants and plants with seeds
The spore is the agent of dispersal in the first, whereas the seed functions in dispersal in the second.
Where would you find a microsporangium in the life cycle of a pine
At the base of the sporophyll in a pollen cone.
Which of these plants is believed to be the only survivor of the oldest branch of the angiosperm lineage
The small shrub Amborella
The male gametophyte in _______ is contained within a pollen grain
angiosperms
Which of the following is incorrectly paired w/ its function
Procambium--meristematic tissue
which of the following is incorrectly paired with its type of life cycle
wheat--biennial
which of the following cells are dead at functional maturity
all of the above
in what direction does a plant cell enlarge
perpendicular to the orientation to cellulose
what do organ identity genes code for
transcription factors
What is a usual sign of the change of the apical meristem from the juvenile to the mature phase
a change in the morphology of leaves
which of the following is essential to establishing the axial polarity of a plant
the assymetric 1st division of a zygote
supporting cells with thickened secondary walls
schlerenchyma
supporting cells with thickened primary walls
collenchyma
tapered xylem cells with lignin in cell walls
tracheids
bundles of long-schlerenchyma cells
fibers
cambium cells that produce secondary xylem and phloem
fusiform initials
layer from which lateral roots originate
pericycle
parenchyma cells with chloroplasts in leaves
mesophyll
protective coat made of cork and cork cambium
periderm
cell layer in root regulating movement into stele
endodermis
parenchyma cells inside vascular ring in dicot stem
pith
Adaptations for terrestrial life seen in all plants are
Sporopollenin
Plants are thought to be most closely related to charophyceans based on
All of the above
Megaphylls
Are leaves with branching vascular systems
4. Bryophyes differ from other land plant groups because
gametophyte generation is dominant
Which of the following plant groups is incorrectly paired with its gametophyte generation?
Fern-frond growing from rhizome
The evolution of sporopollenin was important to the movement of plants onto land because it
Provided a tough coating for spores
If a plant's life cycle includes both a male and female gametophyte, the sporophyte plant must be
Heterosporous
Xylem and Phloem are found in
Vascular plants
Alternation of generations may have evolved in land plants when
Zygote underwent mitotic divisions
Large stores of organic carbon that help to stabilize atmospheric carbon dioxide concentrations are found in
Peat
Protacheophyte polysporangiophytes are
Silurian fossils
How many generations are represented in a pine seed? 3
seed coat from parent sporophyte, food supply from gametophyte, and sporophyte embryo
An example of co-evolution is
A flower with nectar guides that direct bees to its nectaries
Which of the following is incorrect? Monocots typically have
A taproot
Axillary buds
Form at nodes
A leaf trace is
A branch from a vascular bundle that extends into a leaf
ground meristem
produces the ground tissue system
the zone of cell elongation
is responsible for pushing a root through the soil
secondary xylem and phloem are produced in a root by the
vascular cambium
bark consists of
all of the above
sieve-tube members
are transport cells
clonal analysis of cells of the shoot apex indicates that
a cell's developmental fate is more influenced by position effects
The most recent common ancestor of all land plants was most similar to modern-day members of which group?
c. Charophycea
Peptidoglycan is to the structural integrity of bacteria as ____ is to the structural integrity of plant spores.
e. sporopollenin
Which kind of plant tissue should lack phragmoplasts?
d. tissues performing nuclear division without intervening cytokineses
The following are common to both charophyceans and land plants except
b. lignin.
A number of characteristics are very similar between charophyceans and members of the kingdom Plantae. Of the following, which characteristic does not provide evidence for a close evolutionary relationship between these two groups?
a. alternation of generations
A researcher wants to develop an assay (test) that will distinguish charophyceans and land plants from chlorophyte green algae. Which of the following chemicals would be the best subject for such an assay?
d. glycolate oxidase-an enzyme of peroxisomes that is associated with photorespiration
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 a mitosis most similar to that of land plants?
c. charophyceans
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 charophycean recently washed into the ocean from a freshwater or brackish water source, or a land plant washed into the ocean. Which of the following features would definitively identify this organism as a land plant?
e. presence of embryos
Some green algae exhibit alternation of generations. All land plants exhibit alternation of generations. No charophyceans exhibit alternation of generations. Keeping in mind the recent evidence from molecular systematics, the correct interpretation of these observations is that
b. plants evolved alternation of generations independently of green algae.
Bryophytes have all of the following characteristics except
c. lignified vascular tissue.
Which putative taxon is essentially equivalent to the "embryophytes"?
b. Plantae
protection from predators
B. tracheids and phloem
protection from desiccation
C. secondary compounds
transport of water, minerals, and nutrients
A. nonflagellated sperm
Which of the following was not a challenge for survival of the first land plants?
d. animal predation
The following are all adaptations to life on land except
a. rosette cellulose-synthesizing complexes.
Mitotic activity by the apical meristem of a root makes all of the following more possible except
a. increased length of the above-ground stem.
Which of the following is not a secondary compound of embryophytes?
b. alkaloids
Which event during the evolution of land plants probably made the synthesis of secondary compounds most beneficial?
d. the rise of herbivory
If one were attempting to catalog the largest amount of genetic diversity among plant-like organisms, then which group of organisms should one choose?
b. Viridiplantae
Which of these should have had gene sequences most similar to the charophycean that was the common ancestor of the land plants?
b. early bryophytes
Plant spores give rise directly to
a. sporophytes.
Which of the following statements is true of archegonia?
b. They may temporarily contain sporophyte embryos.
Which of the following is a true statement about plant reproduction?
b. Both male and female bryophytes produce gametangia.
Assuming that they all belong to the same plant, arrange the following structures from smallest to largest.
d. 3, 4, 1, 2
The leaflike appendages of moss gametophytes may be one- to two-cell-layers thick. Consequently, which of these is least likely to be found associated with such appendages?
c. stomata
Each of the following is a general characteristic of bryophytes except
b. vascular tissue.
The following are all true about the life cycle of mosses except
e. gametophytes germinate from spores.
Beginning with the germination of a moss spore, what is the sequence of structures that develop after germination?
c. 4, 5, 2, 1, 3
Bryophytes may feature all of the following at some time during their existence except
a. microphylls.
A fungal infection damages all calyptra, preventing them from performing their function. Which process will be directly hindered as a result?
e. broadcast of spores
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 with the pond without Sphagnum, the pond surrounded by the moss should have
a. a lower pH.
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 efforts?
c. foot
Bryophytes never formed forests (mats maybe, but not forests) because
c. they lack lignified vascular tissue.
In which of the following does the sporophyte depend on the gametophyte for nutrition?
b. moss
Of the following list, flagellated (swimming) sperm are generally present in which groups?
b. 1, 2, 4, 5
The following characteristics all helped seedless plants become better-adapted to land except
a. a dominant gametophyte.
A botanist discovers a new species of plant in a tropical rain forest. After observing its anatomy and life cycle, the following characteristics are noted: flagellated sperm, xylem with tracheids, separate gametophyte and sporophyte generations, and no seeds. This plant is probably most closely related to
c. ferns.
A major change that occurred during the evolution of plants from their algal ancestors was the origin of a branched sporophyte. What advantage would branched sporophytes provide in this stage of the life cycle?
b. increased spore production
Sporophylls can be found in which of the following?
d. pterophytes
Which of the following types of plants would not have been present in the forests that became coal deposits?
c. pine trees
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.
This student has probably found a(n)
e. club moss sporophyte.
Besides oil, what other chemical should be detected in substantial amounts upon chemical analysis of these small spheres?
a. sporopollenins
Closer observation reveals that these small spheres are produced on tiny extensions of the stem, each of which helps compose the pinecone-like structure. Research would reveal that the cone-like structures are called ____, whereas the small, spore-producing extensions of the stem are called ____.
c. strobili; sporophylls
A dissection of the interior of the stem should reveal
a. lignified vascular tissues.
Assuming that they all belong to the same plant, arrange the following structures from largest to smallest (or from most inclusive to least inclusive).
e. 3, 2, 4, 1
If one were building a large, log structure during the Carboniferous period, which plant type(s) would be suitable sources of logs?
d. horsetails and lycophytes
Which of the following is true of seedless vascular plants?
b. Whole forests were once dominated by large, seedless vascular plants.
Working from deep geologic strata toward shallow geologic strata, what is the sequence in which fossils of these groups should make their first appearance?
c. 2, 1, 3, 4
The sporophytes of mosses depend on the gametophytes for water and nutrition. In seed plants, the reverse is true. From which seed plant sporophyte structure(s) do the immature (unfertilized) gametophytes directly gain water and nutrition?
c. sporangia
Which of the following is an ongoing trend in the evolution of land plants?
b. reduction of the gametophyte phase of the life cycle
All of the following cellular structures are found in cells of angiosperm and gymnosperm gametophytes except
d. chloroplasts.
Plants with a dominant sporophyte are successful on land partly because
d. their gametophytes are protected by, and obtain nutrition from, the sporophytes.
Seeds commonly provide for each of the following except
e. desiccation resistance.
In addition to seeds, which of the following characteristics are unique to the seed-producing plants?
c. pollen
Which of the following most closely represents the male gametophyte of seed-bearing plants?
c. pollen grain
Suppose that the cells of seed plants, like the skin cells of humans, produce a pigment upon increased exposure to UV radiation. Rank the cells below, from greatest to least, in terms of the likelihood of producing this pigment.
c. 3, 1, 4, 2
Which number represents the mature gametophyte?
d. 7
Which number represents an embryo?
e. 11
Meiosis is most likely to be represented by which number(s)?
b. 4
Which number represents a megaspore mother cell?
b. 3
Which numbers represent haploid cells or tissues?
e. 5, 7, and 9
The process labeled "6" involves
b. mitosis.
The embryo sac of an angiosperm flower is best represented by which number?
c. 7
In angiosperms, which number represents the event that initiates the formation of endosperm?
d. 10
In seed plants, which structure or material is considered part of a pollen grain?
c. sporopollenin
In terms of alternation of generations, the pollen grains of seed-producing plants are most similar to a
e. fern gametophyte that will bear only antheridia.
Which of these is most important in making the typical seed more resistant to adverse conditions than the typical spore?
c. integument(s)
Gymnosperms differ from both extinct and extant ferns because they
c. have pollen.
The main way that pine trees disperse their offspring is by using
d. windblown seeds.
Generally, wind pollination is most likely to be found in seed plants that grow
b. in dense, single-species stands.
Which of the following statements does not describe a portion of the pine life cycle?
a. Female gametophytes use meiosis to produce eggs.
Which of the following statement is not generally true of the pine life cycle?
d. Pollen grains are very different from pine male gametophytes.
Within a gymnosperm megasporangium, what is the correct sequence in which the following should appear during development, assuming that fertilization occurs?
b. 4, 2, 3, 1
Arrange the following structures, which can be found on male pine trees, from the largest structure to the smallest structure (or from most inclusive to least inclusive).
a. 1, 4, 3, 2, 5
Before pollination occurs, what does an individual flower potentially have that an individual pine cone does not have?
d. structures for dispersing seed or pollen grains
Which trait(s) is (are) shared by modern gymnosperms and angiosperms?
c. 1, 2, and 3
Which structure is common to both gymnosperms and angiosperms?
c. ovule
A botanist discovers a new species of land plant with a dominant sporophyte, chlorophylls a and b, and a cell wall made of cellulose. In assigning this plant to a phylum, all of the following would provide useful information except whether or not the plant has
e. spores.
What is true of stamens, sepals, petals, and pine cone scales?
c. They are modified leaves.
Reptilian embryos are protected from desiccation by a leathery shell. Similarly, sporophytes of both gymnosperms and angiosperms protect embryos within ____, and they also protect male gametophytes against desiccation using ____.
a. ovules; waxy cuticle
e. integuments; sporopollenin
scale of ovulate (ovule-bearing) pine cone
D. female sporophyte
integument of pine nut
D. female sporophyte
egg cell in the embryo sac
B. female gametophyte
fruit
D. female sporophyte
pollen tube
A. male gametophyte
All of the following are sporophyte structures except
b. pollen tubes.
Which of the following statements is not true of monocots?
c. They, along with the eudicots and basal angiosperms, are currently placed in the phylum Anthophyta.
Carpels and stamens are
e. modified sporophylls.
How have fruits contributed to the success of angiosperms?
b. by facilitating dispersal of seeds
In flowering plants, meiosis occurs specifically in the
a. spore mother cells.
Arrange the following structures from largest to smallest, assuming that they belong to two generations of the same angiosperm.
e. 4, 1, 2, 5, 3
Which structure(s) must pass through the micropyle for successful fertilization to occur in angiosperms?
e. both B and C
How many chromosomes should be in a tube cell nucleus?
B. 8
How many chromosomes should be in an endosperm nucleus?
D. 24
How many chromosomes should be in a generative cell nucleus?
B. 8
How many chromosomes should be in an embryo sac nucleus?
B. 8
How many chromosomes should be in an embryo nucleus?
C. 16
Hypothetically, one of the major benefits of double fertilization in angiosperms is to
d. coordinate developmental timing between the embryo and its food stores.
Which of the following flower parts develops into a seed?
a. ovule
Which of the following flower parts develops into a fruit?
d. ovary
A plant whose reproductive parts produce nectar should be expected to
a. have brightly colored reproductive parts.
The fruit of the mistletoe, a parasitic angiosperm, is a one-seeded berry. In members of the genus Viscum, the outside of the seed is viscous (sticky), which permits the seed to adhere to surfaces, such as the branches of host plants or the beaks of birds. What should be expected of the pericarp if the viscosity of Viscum seeds is primarily an adaptation for dispersal rather than an adaptation for infecting host plant tissues?
c. It should be nutritious.
The fruit is made of material high in calories
B. animal digestive tract
The fruit is covered with spines or hooks.
A. animal skin, fur, or feathers
The fruit contains an air bubble.
C. water currents
The fruit has a heavy weight and spheroidal shape.
D. gravity and terrain
The fruit has light, fibrous plumes or puffs.
E. air currents
Over human history, which process has been most important in improving the features of plants that have long been used by humans as staple foods?
b. artificial selection
Which of the following do all fungi have in common?
d. absorption of nutrients
The hydrolytic digestion of which of the following should produce the monomer, an aminated molecule of -glucose?
d. A and C only
If all saprobic fungi in an environment were to suddenly die, which group of organisms should benefit as a whole?
c. prokaryotes
When a mycelium infiltrates an unexploited source of dead organic matter, what are most likely to appear within the food source soon thereafter?
c. exoenzymes
The functional significance of porous septa in certain fungal hyphae is most similar to that represented by the ____ of certain animal cells, and by the ____ of certain plant cells.
b. gap junctions; plasmodesmata
What is the primary role of a mushroom's underground mycelium?
a. absorbing nutrients
What do fungi and arthropods have in common?
d. The protective coats of both groups are made of chitin.
In septate fungi, what structures allow cytoplasmic streaming to distribute needed nutrients, synthesized compounds, and organelles throughout the hyphae?
b. pores in septal walls
What best accounts for the extremely fast growth of a fungal mycelium?
a. a rapid distribution of synthesized proteins by cytoplasmic streaming
The vegetative (nutritionally active) bodies of most fungi are
e. A, B, and C
Both fungus-farming ants and their fungi can synthesize the same structural polysaccharide from the -glucose molecules that are derived from the digestion of plant leaves. What is the synthesized polysaccharide?
b. chitin
Consider two hyphae having equal dimensions: one from a septate species and the other from a coenocytic species. Compared with the septate species, the coenocytic species should have
c. less chitin.
Which of the following terms is not properly associated with the fungi as a kingdom?
c. ecologically important
In fungi, karyogamy does not immediately follow plasmogamy, which
d. results in heterokaryotic cells.
If all of their nuclei are equally active transcriptionally, then the cells of both dikaryotic and heterokaryotic fungi are essentially like ____ cells in terms of the gene products they can make.
b. diploid
What is a fungal process that has the opposite effect on chromosome number than the effect of meiosis?
e. karyogamy
If a single, diploid G2 nucleus in an ascus contains 400 nanograms (ng) of DNA, then a single mature ascospore of this species should contain ____ ng of DNA, carried on a total of ____ chromosomes.
a. 100; 7
What is the ploidy of a single mature Neurospora ascospore?
a. haploid
Each of the eight ascospores present at the end of mitosis has the same chromosome number and DNA content (ng) as each of the four cells at the end of meiosis. What must have occurred between the round of meiosis and the round of mitosis?
e. S phase
Which of the following statements is true of deuteromycetes?
c. They are the group of fungi that have, at present, no known sexual stage.
What is the greatest threat to plant diversity?
e. human population growth
Which of the following is not a valid argument for preserving tropical forests?
a. People in the tropics do not need to increase agricultural output.
Assume that a botanist was visiting a tropical region for the purpose of discovering plants with medicinal properties. All of the following might be ways of identifying potentially useful plants except
b. observing which plants are the most used food plants.
You are studying a plant from the arid southwestern United States. Which of the following adaptations is least likely to have evolved in response to water shortages?
b. development of large leaf surfaces to absorb water
Which part of a plant absorbs most of the water and minerals taken up from the soil?
b. root hairs
An evolutionary adaptation that increases exposure of a plant to light in a dense forest is
c. apical dominance.
A person working with plants may remove apical dominance by doing which of the following?
a. pruning
What effect does "pinching back" have on a houseplant?
d. produces a plant that will grow fuller
Land plants are composed of all the following tissue types except
a. mesodermal.
Vascular plant tissue includes all of the following cell types except
e. cambium cells.
living cells that lack nuclei and ribosomes; they transport sugars and other organic nutrients
E. sieve cells
the least specialized plant cells, which serve general metabolic, synthetic, and storage functions
A. parenchyma
cells with unevenly thickened primary walls that support still-elongating parts of the plant
B. collenchyma
mature cells without protoplasts with thick, lignified secondary walls that may or may not function in transport
C. sclerenchyma
The vascular bundle in the shape of a single central cylinder in a root is called the
b. stele.
One important difference between the anatomy of roots and the anatomy of leaves is that
c. a waxy cuticle covers leaves but is absent in roots.
A student examining leaf cross sections under a microscope finds many loosely packed cells with relatively thin cell walls. The cells have numerous chloroplasts. What type of cells are these?
a. parenchyma
The best word to describe the growth of plants in general is
c. indeterminate.
A friend has discovered a new plant and brings it to you to classify. The plant has the following characteristics: a taproot system with growth rings evident in cross section and a layer of bark around the outside. Which of the following best describes the new plant?
b. woody eudicot
The driving force that pushes the root tip through the soil is due primarily to
c. elongation of cells behind the root apical meristem.
Shoot elongation in a growing bud is due primarily to
d. cell elongation localized in each internode.
Axillary buds
b. develop from meristematic cells left by the apical meristem.
Gas exchange, necessary for photosynthesis, can occur most easily in which leaf tissue?
c. spongy mesophyll
Which of the following is the correct sequence from the growing tips of the root upward?
e. I, V, III, II, IV
Which of the following is incorrectly paired with its structure and function?
c. pericycle-waterproof ring of cells surrounding the central stele in roots
Which of the following illustrates the idea that the fate of a cell is a direct result of its position?
e. A, B, and C
Which of the following root tissues gives rise to lateral roots?
e. pericycle
A woody eudicot is represented by
d. IV only.
A monocot stem is represented by
b. II only.
A plant that is at least three years old is represented by
d. IV only.
A leaf primordium is initiated as a small mound of tissue on the flank of a dome-shaped shoot apical meristem. The earliest physical evidence of the site of a newly forming leaf primordium would be
c. pre-prophase bands parallel to the surface of the meristem in subsurface cells of the shoot apical meristem.
Pores on the leaf surface that function in gas exchange are called
d. stomata.
Which of the following is a true statement about growth in plants?
b. Some plants lack secondary growth.
All of the following cell types are correctly matched with their functions except
e. companion cell-formation of secondary xylem and phloem
As a youngster, you drive a nail in the trunk of a young tree that is 3 meters tall. The nail is about 1.5 meters from the ground. Fifteen years later, you return and discover the tree has grown to a height of 30 meters. The nail is now ____ meters above the ground.
b. 1.5
What tissue makes up most of the wood of a tree?
b. secondary xylem
The vascular system of a three-year-old eudicot stem consists of
e. 3 rings of xylem and 1 of phloem.
If you were able to walk into an opening cut into the center of a large redwood tree, when you exit from the middle of the trunk (stem) outward, you would cross, in order,
a. the annual rings, phloem, and bark.
Which of the following is true of bark?
a. It is composed of phloem plus periderm.
Bark becomes scaly because
d. cork cambium divides only parallel to the surface, and thus does not increase in circumference.
Suppose George Washington completely removed the bark from around the base of a cherry tree but was stopped by his father before cutting the tree down. The leaves retained their normal appearance for several weeks, but the tree eventually died. The tissue(s) that George left functional was (were) the
b. xylem.
Additional vascular tissue produced as secondary growth in a root originates from which cells?
a. vascular cambium
While studying the plant Arabidopsis, a botanist finds that an RNA probe produces colored spots in the sepals of the plant. From this information, what information can be inferred?
d. The RNA probe is specific to a gene active in sepals.
Before differentiation can begin during the processes of plant cell and tissue culture, parenchyma cells from the source tissue must
b. undergo dedifferentiation.
The polarity of a plant is established when
a. the zygote divides.
"Totipotency" is a term used to describe the ability of a cell to give rise to a complete new organism. In plants, this means that
c. cell differentiation depends largely on the control of gene expression.
According to the ABC model of floral development, a showy ornamental flower with multiple sepals and petals but no stamens or carpels would express
d. A and B genes only.
Which of the following would be least likely to affect osmosis in plants?
c. receptor proteins in the membrane
Active transport involves all of the following except the
a. slow movement through the lipid bilayer of a membrane.
Like many plant processes, transport of various materials in plants at the cellular level requires all of the following except
e. xylem membranes.
Which of the following is not a function of the plasma membrane proton pump?
d. equalizes the charge on each side of a membrane
The amount and direction of movement of water in plants can always be predicted by measuring which of the following?
e. water potential ( )
If P = 0.3 MPa and S = -0.45 MPa, the resulting is
c. -0.15 MPa.
The value for in root tissue was found to be -0.15 MPa. If you take the root tissue and place it in a 0.1 M solution of sucrose ( = -0.23), net water flow would
a. be from the tissue into the sucrose solution.
Compared to a cell with few aquaporins in its membrane, a cell containing many aquaporins will
a. have a faster rate of osmosis.
Some botanists argue that the entire plant should be considered as a single unit rather than a composite of many individual cells. Which of the following cellular structures cannot be used to support this view?
d. tonoplast
Which of the following statements is false about bulk flow?
d. It depends on the force of gravity on a column of water.
Which of the following statements about xylem is incorrect?
c. It transports mainly sugars and amino acids.
Which of the following would likely not contribute to the surface area available for water absorption from the soil by a plant root system?
b. endodermis
Root hairs are most important to a plant because they
c. increase the surface area for absorption.
What is the role of proton pumps in root hair cells?
b. acquire minerals from the soil
In plant roots, the Casparian strip is correctly described by which of the following?
d. It ensures that all water and dissolved substances must pass through a cell before entering the stele.
Pine seedlings grown in sterile potting soil grow much slower than seedlings grown in soil from the area where the seeds were collected. This is most likely because
e. both B and D
A water molecule could move all the way through a plant from soil to root to leaf to air and pass through a living cell only once. This living cell would be a part of which structure?
d. the endodermis
The following factors may sometimes play a role in the movement of sap through xylem. Which one depends on the direct expenditure of ATP by the plant?
d. concentration of ions in the symplast
What is the main cause of guttation in plants?
a. root pressure
One is most likely to see guttation in small plants when the
b. root pressure exceeds transpiration pull.
What is the main force by which most of the water within xylem vessels moves toward the top of a tree?
c. evaporation of water through stoma
In which plant cell or tissue would the pressure component of water potential most often be negative?
b. stem xylem
Water potential is generally most negative in which of the following parts of a plant?
a. mesophyll cells of the leaf
Which of the following has the lowest (most negative) water potential?
e. leaf air spaces
Which of the following is responsible for the cohesion of water molecules?
c. hydrogen bonds between the oxygen atom of one water molecule and a hydrogen atom of another water molecule
Transpiration in plants requires all of the following except
d. active transport through xylem cells.
Which of the following statements about transport in plants is false?
e. Gymnosperms can sometimes develop especially high root pressure, which may account for the rise of water in tall pine trees without transpiration pull.
Active transport would be least important in the normal functioning of which of the following plant tissue types?
b. stem xylem
Which of the following statements is false concerning the xylem?
d. Movement of materials is by mass flow; materials move owing to a turgor pressure gradient from "source" to "sink."
Xylem vessels, found in angiosperms, have a much greater internal diameter than tracheids, the only xylem conducting cells found in gymnosperms. The tallest living trees, redwoods, are gymnosperms. Which of the following is an advantage of tracheids over vessels for long-distance transport to great heights?
d. Only A and C are correct.
Water rises in plants primarily by the cohesion-tension model. Which of the following is not true about this model?
b. The "tension" of this model represents the excitability of the xylem cells.
Assume that a particular chemical interferes with the establishment and maintenance of proton gradients across the membranes of plant cells. All of the following processes would be directly affected by this chemical except
c. xylem transport.
Guard cells do which of the following?
e. help balance the photosynthesis-transpiration compromise
All of the following normally enter the plant through the roots except
a. carbon dioxide.
Photosynthesis begins to decline when leaves wilt because
d. stomata close, preventing CO2 entry into the leaf.
The water lost during transpiration is an unfortunate side effect of the plant's exchange of gases. However, the plant derives some benefit from this water loss in the form of
d. A and B only
Ignoring all other factors, what kind of day would result in the fastest delivery of water and minerals to the leaves of a tree?
b. warm, dry day
If the guard cells and surrounding epidermal cells in a plant are deficient in potassium ions, all of the following would occur except
d. leaf temperatures would decrease.
The opening of stomata is thought to involve
a. an increase in the osmotic concentration of the guard cells.
Which of the following experimental procedures would most likely reduce transpiration while allowing the normal growth of a plant?
b. increasing the level of carbon dioxide around the plant
Guard cells are the only cells in the epidermis that contain chloroplasts and can undergo photosynthesis. This is important because
d. ATP is required to power proton pumps in the guard cell membranes.
All of the following are adaptations that help reduce water loss from a plant except
a. transpiration.
Which of the following best explains why CAM plants are not tall?
a. They would be unable to move water and minerals to the top of the plant during the day.
As a biologist, it is your job to look for plants that have evolved structures with a selective advantage in dry, hot conditions. Which of the following adaptations would be least likely to meet your objective?
e. plants that do not produce abscisic acid and have a short, thick tap root
Phloem transport of sucrose can be described as going from "source to sink." Which of the following would not normally function as a sink?
d. mature leaf
Which of the following is a correct statement about sugar movement in phloem?
b. Movement can occur both upward and downward in the plant.
Phloem transport is described as being from source to sink. Which of the following would most accurately complete this statement about phloem transport as applied to most plants in the late spring? Phloem transports ____ from the ____ source to the ____ sink.
b. sugars; leaf; apical meristem
Arrange the following five events in an order that explains the mass flow of materials in the phloem.
c. 2, 4, 3, 1, 5
Water flows into the source end of a sieve tube because
b. sucrose has been actively transported into the sieve tube, making it hypertonic.
Which one of the following statements about transport of nutrients in phloem is false?
b. Companion cells control the rate and direction of movement of phloem sap.
According to the pressure flow hypothesis of phloem transport,
a. solute moves from a high concentration in the "source" to a lower concentration in the "sink."
Plants do not have a circulatory system like that of some animals. If a given water molecule did "circulate" (that is, go from one point in a plant to another and back), it would require the activity of
e. both the xylem and the phloem.
Which of the following describes the fate of most of the water taken up by a plant?
c. It is lost during transpiration.
Most of the dry weight of a plant is the result of uptake of
c. CO2 through stomata in leaves.
Organic molecules make up what percentage of the dry weight of a plant?
e. 96%
In hydroponic culture, what is the purpose of bubbling air into the solute?
b. to provide oxygen to root cells
When performing a mineral nutrition experiment, researchers use water from a glass still. Why is it not a good idea to use regular distilled water from a stainless steel still?
c. Metal ions dissolving off the steel may serve as micronutrients.
Which of the following essential nutrients does not have a role in photosynthesis, either as a structural component or in the synthesis of a component?
e. K
Which of the following is of least concern to a researcher in a mineral nutrition experiment?
d. ability of a laboratory balance to weigh very small quantities of chemicals
Which two elements make up more than 90% of the dry weight of plants?
d. oxygen and carbon
The bulk of a plant's dry weight is derived from
b. CO2.
What are the three main elements on which plant growth and development depend?
c. oxygen; carbon; hydrogen
A growing plant exhibits chlorosis of the leaves of the entire plant. The chlorosis is probably due to a deficiency of which of the following macronutrients?
c. nitrogen
Which of the following elements is incorrectly paired with its function in a plant?
e. sulfur—component of DNA; activates some enzymes
Reddish-purple coloring of leaves, especially along the margins of young leaves, is a typical symptom of deficiency of which element?
d. P
Which of the following best describes the general role of micronutrients in plants?
a. They are cofactors in enzymatic reactions.
Which of the following is not true of micronutrients in plants?
d. They are the essential elements of small size and molecular weight.
What is meant by the term chlorosis?
c. the yellowing of leaves due to decreased chlorophyll production
If an African violet has chlorosis, which of the following elements might be a useful addition to the soil?
e. magnesium
Iron deficiency is often indicated by chlorosis in newly formed leaves. This suggests that
a. iron is an immobile nutrient in plants.
There are several properties of a soil in which typical plants would grow well. Of the following, which would be the least conducive to plant growth?
c. high clay content
A soil well suited for the growth of most plants would have all of the following properties except
e. a high pH.
What soil(s) is(are) the most fertile?
e. both humus and loam
The best conclusion from the data in the figure above is that the plant
b. grows fastest in 5 to 10% air.
The best explanation for the shape of this growth response curve is that
e. the roots require oxygen for respiration and growth.
Why does overwatering a plant kill it?
c. The roots cannot get air.
What should be added to soil to prevent minerals from leaching away?
a. humus
Which soil mineral is most likely leached away during a hard rain?
d. NO3-
All of the following contributed to the dust bowl in the American southwest during the 1930s except
b. cutting of mature trees.
The N-P-K percentages on a package of fertilizer refer to the
d. percentages of three important mineral nutrients.
Based on the information provided above, what is the most likely cause of the decline in productivity?
d. The soil has become hyperosmotic to the roots due to salination.
If you were the county agriculture agent, what would be the best advice you could give the farmer who owns the field under study in the figure above?
a. Plant a variety of cotton that requires less water and can tolerate salinity.
A young farmer purchases some land in a relatively arid area and is interested in earning a reasonable profit for many years. Which of the following strategies would best allow such a goal to be achieved?
d. selecting crops adapted to arid areas
A farming commitment that embraces a variety of methods that are conservation-minded, environmentally safe, and profitable is called
e. sustainable agriculture.
Nitrogen fixation is a process that
d. converts nitrogen gas into ammonia.
Why is nitrogen fixation such an important process?
b. Fixed nitrogen is most often the limiting factor in plant growth.
In what way do nitrogen compounds differ from other minerals needed by plants?
b. Only nitrogen requires the action of bacteria to be made available to plants.
Most crop plants acquire their nitrogen mainly in the form of
d. NO3-.
The enzyme complex nitrogenase catalyzes the reaction that reduces atmospheric nitrogen to
b. NH3.
In a root nodule, the gene coding for nitrogenase
e. is part of the Rhizobium chromosome.
The most efficient way to increase essential amino acids in crop plants for human consumption is to
a. breed for higher yield of deficient amino acids.
Among important crop plants, nitrogen-fixing root nodules are most commonly an attribute of
b. legumes.
You are weeding your garden when you accidentally expose some roots. You notice swellings (root nodules) on the roots. Most likely your plant
c. is benefiting from a mutualistic bacterium.
Which of the following is a true statement about nitrogen fixation in root nodules?
c. Leghemoglobin helps maintain a low O2 concentration within the nodule.
The function of a root nodule's leghemoglobin is to
b. regulate the supply of oxygen to Rhizobium.
A woodlot was sprayed with a fungicide. What would be the most serious effect of such spraying?
c. a decrease in tree growth due to the death of mycorrhizae
What is the mutualistic association between roots and fungi called?
c. mycorrhizae
Hyphae form a covering over roots. Altogether, these hyphae create a large surface area that helps to do which of the following?
a. aid in absorbing minerals and ions
Which of the following is a primary difference between ectomycorrhizae and endomycorrhizae?
c. Ectomycorrhizae do not penetrate root cells, whereas endomycorrhizae grow into invaginations of the root cell membranes.
The earliest vascular plants on land had underground stems (rhizomes) but no roots. Water and mineral nutrients were most likely obtained by
c. absorption by symbiotic fungi.
Dwarf mistletoe grows on many pine trees in the Rockies. Although the mistletoe is green, it is probably not sufficiently active in photosynthesis to produce all the sugar it needs. The mistletoe also produces haustoria. Thus, dwarf mistletoe growing on pine trees is best classified as
e. a parasite.
What are epiphytes?
d. plants that grow on other plants but do not obtain nutrients from their hosts
Carnivorous plants have evolved mechanisms that trap and digest small animals. The products of this digestion are used to supplement the plant's supply of
d. minerals.
The products of meiosis in plants are always which of the following?
a. spores
Which of the following is the correct sequence during alternation of generations in a flowering plant?
a. sporophyte-meiosis-gametophyte-gametes-fertilization-diploid zygote
All of the following are features of angiosperms except
d. a small (reduced) sporophyte.
Based on studies of plant evolution, which flower part is not a modified leaf?
e. receptacle
All of the following floral parts are directly involved in pollination or fertilization except the
d. carpel.
Which of the following is the correct order of floral organs from the outside to the inside of a complete flower?
d. sepals-petals-stamens-carpels
All of the following are primary functions of flowers except
b. photosynthesis.
Meiosis occurs within all of the following flower parts except the
b. style.
A perfect flower is fertile, but may be either complete or incomplete. Which of the following correctly describes a perfect flower?
e. It has both stamens and carpels.
Carpellate flowers
e. develop into fruits.
Which of the following types of plants is not able to self-pollinate?
a. dioecious
In flowering plants, pollen is released from the
a. anther.
In the life cycle of an angiosperm, which of the following stages is diploid?
d. microsporocyte
Where does meiosis occur in flowering plants?
e. megasporocyte and microsporocyte
Which of the following is a correct sequence of processes that takes place when a flowering plant reproduces?
c. meiosis-pollination-nuclear fusion-formation of embryo and endosperm
Which of these is incorrectly paired with its life-cycle generation?
a. anther—gametophyte
Which of the following is the correct sequence of events in a pollen sac?
e. microsporocyte-meiosis-microspores-mitosis-two haploid cells per pollen grain
Which of the following occurs in an angiosperm ovule?
b. A megaspore mother cell undergoes meiosis.
Where and by which process are sperm produced in plants?
c. mitosis in male gametophytes
In which of the following pairs are the two terms equivalent?
b. embryo sac—female gametophyte
Which of the following is the male gametophyte of a flowering plant?
c. pollen grain
In flowering plants, a mature male gametophyte contains
c. two sperm nuclei and one tube cell nucleus.
Within the female gametophyte, three mitotic divisions of the megaspore produce
a. three antipodal cells, two polar nuclei, one egg, and two synergids.
Which cell(s), after fertilization, give(s) rise to the embryo plant?
b. B
Which cell(s) become(s) the triploid endosperm?
c. C
Which cell(s) guide(s) the pollen tube to the egg cell?
a. A
What is the relationship between pollination and fertilization in flowering plants?
d. Pollination brings gametophytes together so that fertilization can occur.
Recent research has shown that pollination requires that carpels recognize pollen grains as "self or nonself." For self-incompatibility, the system requires
b. the rejection of self cells.
Genetic incompatibility does not affect the
a. attraction of a suitable insect pollinator.
You are studying a plant from the Amazon that shows strong self-incompatibility. To characterize this reproductive mechanism, you would look for
a. ribonuclease (RNAase) activity in stigma cells.
As flowers develop, which transition does not occur?
d. The tube nucleus becomes a sperm nucleus.
The integuments of an ovule function to do what?
c. form a seed coat
Which of the following events suggests there is a change in the egg cell membrane after penetration by a sperm?
b. Ca2+ builds up in the cytoplasm of the egg.
A fruit includes
e. both A and B
Which of the following is not an advantage of an extended gametophyte generation in plants?
e. Endosperm forms a protective seed coat.
What is typically the result of double fertilization in angiosperms?
c. Both a diploid embryo and triploid endosperm are formed.
Which of the following statements regarding the endosperm is false?
d. It develops from the fertilized egg.
In angiosperms, products of the terminal cell become the
b. proembryo.
Which of the following statements is correct about the basal cell in a zygote?
b. It forms the suspensor that anchors the embryo.
What is the embryonic root called?
d. radicle
Which of the following "vegetables" is botanically a fruit?
e. green beans
Which of the following statements about fruits is false?
b. All normal fruits have seeds inside them.
Fruits develop from
d. ovaries.
The first step in the germination of a seed is usually
c. imbibition of water.
Which of the following is not true of the hypocotyl hook?
a. It is the first structure to emerge from a eudicot seed.
In plants, which of the following could be an advantage of sexual reproduction as opposed to asexual reproduction?
a. genetic variation
A disadvantage of monoculture is that
b. genetic uniformity makes a crop vulnerable to a new pest or disease.
Which of the following is true about vegetative reproduction?
e. It produces clones.
Which of the following is a true statement about clonal reproduction in plants?
c. Making cuttings of ornamental plants is a form of fragmentation.
Which of the following statements about a seed produced by apomixis is incorrect?
b. The embryo consists of diploid cells derived from fertilization of a haploid egg by a haploid sperm.
All of the following could be considered advantages of asexual reproduction in plants except
e. adaptation to change.
Regardless of where in the world a vineyard is located, in order for the winery to produce a Burgundy, it must use varietal grapes that originated in Burgundy, France. The most effective way for a new California grower to plant a vineyard to produce Burgundy is to
e. graft varietal Burgundy grape scions onto native (Californian) root stocks.
Under which conditions would asexual plants have the greatest advantage over sexual plants?
c. a relatively constant environment with infrequent disturbances
Which of the following statements is true of protoplast fusion?
b. It can be used to form new plant varieties by combining genomes from two plants.
Which of the following statements is correct about protoplast fusion?
c. It can be used to form new plant species.
The most immediate potential benefits of introducing genetically modified crops include
d. increasing crop yield.
Which of the following is not a scientific concern relating to creating genetically modified crops?
d. The monetary costs of growing genetically modified plants are significantly greater than traditional breeding techniques.
Currently available transgenic plants have been modified for all of the following traits except
b. nitrogen fixation.
A friend has discovered a new plant and brings it to you to classify. The plant has the following characteristics: a taproot system with growth rings evident in cross section and a layer of bark around the outside. Which of the following best describes the new plant?
b. woody eudicot
You are studying a plant from the arid southwestern United States. Which of the following adaptations is least likely to have evolved in response to water shortages?
b. development of large leaf surfaces to absorb water
Land plants are composed of all the following tissue types except
a. mesodermal.
long, thin tapered cells with lignified cell walls that function in support and permit water to flow through pits
D. tracheids
living cells that lack nuclei and ribosomes; they transport sugars and other organic nutrients
E. sieve cells
One important difference between the anatomy of roots and the anatomy of leaves is that
c. a waxy cuticle covers leaves but is absent in roots.
The photosynthetic cells in the interior of a leaf are what kind of cells?
a. parenchyma
Gas exchange, necessary for photosynthesis, can occur most easily in which leaf tissue?
c. spongy mesophyll
Which of the following is the correct sequence from the growing tips of the root upward?
e. I, V, III, II, IV
A monocot stem is represented by
b. II only.
A dicot root is represented by
a. I only.
Pores on the leaf surface that function in gas exchange are called
d. stomata.
All of the following cell types are correctly matched with their functions except
e. companion cell-formation of secondary xylem and phloem
What tissue makes up most of the wood of a tree?
b. secondary xylem
The vascular system of a three-year-old eudicot stem consists of
e. 3 rings of xylem and 1 of phloem.
Which of the following would be least likely to affect osmosis in plants?
c. receptor proteins in the membrane
The amount and direction of movement of water in plants can always be predicted by measuring which of the following?
e. water potential ()
Which of the following statements about xylem is incorrect?
c. It transports mainly sugars and amino acids.
In plant roots, the Casparian strip is correctly described by which of the following?
d. It ensures that all water and dissolved substances must pass through a cell before entering the stele.
What is the main cause of guttation in plants?
a. root pressure
Which of the following is responsible for the cohesion of water molecules?
c. hydrogen bonds between the oxygen atom of one water molecule and a hydrogen atom of another water molecule
Transpiration in plants requires all of the following except
d. active transport through xylem cells.
Guard cells do which of the following?
e. help balance the photosynthesis-transpiration compromise
All of the following normally enter the plant through the roots except
a. carbon dioxide
The opening of stomata is thought to involve
a. an increase in the osmotic concentration of the guard cells.
Which of the following is a correct statement about sugar movement in phloem?
b. Movement can occur both upward and downward in the plant.
Phloem transport is described as being from source to sink. Which of the following would most accurately complete this statement about phloem transport as applied to most plants in the early spring? Phloem transports ____ from the ____ source to the ____ sink.
Dd. sugars; root; leaf
Arrange the following five events in an order that explains the mass flow of materials in the phloem.
c. 2, 4, 3, 1, 5
According to the pressure flow hypothesis of phloem transport,
a. solute moves from a high concentration in the "source" to a lower concentration in the "sink."
Which of the following describes the fate of most of the water taken up by a plant?
c. It is lost during transpiration.
The best conclusion from the data in the figure above is that the plant
b. grows fastest in 5 to 10% air.
Which soil mineral is most likely leached away during a hard rain?
d. NO3-
What is the mutualistic association between roots and fungi called?
c. mycorrhizae
What is the embryonic root called?
d. radicle
Which of these structures is unique to the seed of a monocot?
c. coleoptile
The first step in the germination of a seed is usually
c. imbibition of water.
In plants, which of the following could be an advantage of sexual reproduction as opposed to asexual reproduction?
a. genetic variation
The step(s) between a plant's perception of a change in the environment and the plant's response to that change is (are) best called
d. signal transduction.
We know from the experiments of the past that plants bend toward light because
c. cell expansion is greater on the dark side of the stem.
Plant hormones can be characterized by all of the following except that they
c. function independently of other hormones.
Which plant hormones might be used to enhance stem elongation and fruit growth?
b. auxins and gibberellins
Which plant hormone(s) is (are) most closely associated with cell division?
b. cytokinin
The results of this experiment, shown on the left of the graph (area A), may be used to
d. show a correlation between plant height and gibberellin concentration.
This experiment suggests that the unknown amount of gibberellin in the experimental plant (B) is approximately
c. 0.1 g/mL.
If you were shipping green bananas to a supermarket thousands of miles away, which of the following chemicals would you want to eliminate from the plants' environment?
c. ethylene
In order to flower, a short-day plant needs a
d. night that is longer than a certain length.
Florigen is a flowering signal, not yet chemically identified, found in
b. leaves
If you wanted to genetically engineer a plant to be more resistant to drought, increasing amounts of which of the following hormones might be a good first attempt?
a. abscisic acid
What is the phenomenon that is causing the bean seedling to bend in Figure 22-1?
b. phototropism
An organism's "biological clock" is set by
c. signals from the environment.