BIO test MC
The mutualistic associations between bacteria and plants will
All the above are true.
Which of these represents the female gametophyte generation of an angiosperm?
An embryo sac
Which of these structures is/are produced by fertilization of egg and sperm?
An embryonic sporophyte Submit
Plants and animals respond differently to the environment. Which statement most accurately compares the responses of plants and animals to changes in their environment?
Animals tend to respond to changes in their environment by movement; plants tend to respond to changes in their environment by growth.
Select the correct statement about plant life cycles.
At some point in the life cycle of all plants, the sporophyte is dependent on its gametophyte parent. Submit
Why do coleoptiles grow toward light?
Auxin moves away from the light to the shady side.
The following question refer to the diagram of an embryo sac of an angiosperm shown in the figure. Based on the figure, which cell(s), after fertilization, give(s) rise to the embryo plant?
B
What typically results from double fertilization in angiosperms?
Both a diploid embryo and triploid endosperm are formed.
Please use the following information to answer the question below. Fairy rings are circles of fungi that often appear in open meadows and in forest areas. In the soil beneath the fungi is an ever-extending mycelium. As the mycelium spreads to seek more food, it sometimes will produce the fungi we see above ground. The figure depicts the outline of a fairy ring that has appeared overnight in an open meadow, as viewed from above. The ring represents the farthest advance of this mycelium through the soil. Locations A−−D are all 0.5 meters below the soil surface. What is the most probable location of the oldest portion of this mycelium?
C
The following question refer to the diagram of an embryo sac of an angiosperm shown in the figure. Based on the figure, which cell(s) become(s) the triploid endosperm?
C
The bulk of a plant's dry weight is derived from
CO2.
In a tissue culture experiment, parenchyma tissue was used as a source to develop a new plant. However, the parenchyma tissue did not have enough hormones, so a group of undifferentiated cells, called callus, formed. Which one of the following could happen if the callus was supplemented with specific hormones?
Callus supplemented with auxin and cytokinin would produce root and shoot buds, respectively.
Which of the following is a true statement about angiosperm carpels?
Carpels surround and nourish the female gametophyte.
What is the fate of a flaccid cell in pure water with zero water potential?
Cell enlarges.
Which of these represents the male gametophyte generation of an angiosperm?
Cells within a pollen grain
Select the correct statement about charophytes, a taxon of green algae.
Charophytes and land plants share three distinctive traits.
Which of the following statements is true of the pine life cycle?
Conifer pollen grains contain male gametophytes.
________ is produced in roots and moves up the plant in xylem sap to influence organ formation.
Cytokinin
Please use the following information to answer the question below. Fairy rings are circles of fungi that often appear in open meadows and in forest areas. In the soil beneath the fungi is an ever-extending mycelium. As the mycelium spreads to seek more food, it sometimes will produce the fungi we see above ground. The figure depicts the outline of a fairy ring that has appeared overnight in an open meadow, as viewed from above. The ring represents the farthest advance of this mycelium through the soil. Locations A−−D are all 0.5 meters below the soil surface. All four locations are 0.5 m below the surface. On a breezy day with prevailing winds blowing from left to right, where should one expect to find the highest concentration of free basidiospores in an air sample?
D
Please use the following information to answer the question below. Fairy rings are circles of fungi that often appear in open meadows and in forest areas. In the soil beneath the fungi is an ever-extending mycelium. As the mycelium spreads to seek more food, it sometimes will produce the fungi we see above ground. The figure depicts the outline of a fairy ring that has appeared overnight in an open meadow, as viewed from above. The ring represents the farthest advance of this mycelium through the soil. Locations A−−D are all 0.5 meters below the soil surface. At which location should one find the lowest concentration of fungal enzymes, assuming that the enzymes do not diffuse far from their source and that no other fungi are present in this habitat?
D
Which of these structures is diploid?
D
Select the correct statement describing the life cycle of angiosperms.
Double fertilization in the life cycle of seed plants results in the production of a diploid zygote and a triploid endosperm nucleus.
Select the correct statement about double fertilization in the angiosperm life cycle.
Double fertilization produces a diploid sporophyte and a triploid endosperm.
The molecule most involved in the flowering process is __________.
FT protein
Which of the following statements correctly describes a portion of the pine life cycle?
Female gametophytes use mitosis to produce eggs.
Which description(s) apply(ies) equally well to fungal spores produced both sexually and asexually?I. They are typically dispersed by wind and water.II. Spores that germinate produce new mycelium.III. They are produced in large numbers.
I, II, and III
Which of the following statements are true of monocots?I. Over 25% of extant angiosperms are monocots.II. Monocots include both crop plants and ornamental plants.III. Monocots are most closely related to eudicots.IV. Monocots possess multiple cotyledons.
I, II, and III
Commonalities to both charophytes and vascular land plants includeI. sporopollenin.II. lignin.III. chlorophyll a.IV. cellulose.V. chlorophyll b.
I, III, IV, and V only
Lichens are symbiotic associations of fungi andI. mosses.II. cyanobacteria.III. green algae.IV. gymnosperms
II and III
Plasmogamy can directly result in which of the following?I. cells with a single haploid nucleusII. heterokaryotic cellsIII. cells with two diploid nuclei
II only
A monocot stem is represented in the figure by
II only.
Adaptations in plants to life on land includeI. rings of cellulose-synthesizing complexes.II. cuticles.III. tracheids.IV. reduced gametophyte generation.V. multicellular, dependent embryos.
II, III, IV, and V only
The following question(s) refer to the phylogenetic trees. Which tree depicts the closest relationship between zygomycetes and chytrids?
III
The following question(s) refer to the phylogenetic trees. Which tree depicts all of the currently recognized major groups of fungi?
IV
A plant that is at least 3 years old is represented in the figure by
IV only. Submit
Which of the following is a true statement about plant reproduction?
In bryophytes, the dominant generation consists of haploid gametophytes.
The Casparian strip in plant roots is correctly described by which of the following?
It ensures that all water and dissolved substances must pass through a cell membrane before entering the stele.
Which of the following is true about vegetative reproduction?
It produces clones of the parent plant.
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 fruit if the viscosity of Viscum seeds is primarily an adaptation for dispersal rather than an adaptation for infecting host plant tissues?
It should be nutritious.
If a plant is infected with nitrogen-fixing bacteria, what is the most probable effect on the plant?
It will likely grow faster than an uninfected plant.
If a wide-spectrum fungicide that kills all fungal species were used extensively in a forest, what effects would you expect the treatment to have on the forest vegetation?
It would greatly reduce the ability of most plants to take up water and minerals from soil.
For this pair of items, choose the option that best describes their relationship.(a) The average size of particles that constitute silt(b) The average size of particles that constitute clay
Item (a) is larger than item (b).
Which of the following essential nutrients plays an essential role in the opening and closing of the stomatal aperture?
K
Which of the following chemical equations summarizes the reactions in photosynthesis?
Light energy + 6CO2 + 6H2O →→ C6H12O6 + 6O2
Which of the following is a true statement about clonal reproduction in plants?
Making cuttings of ornamental plants is a form of fragmentation.
What are the products of meiosis in the life cycle of a seed plant?
Megaspores or microspores
Gymnosperms were most abundant during the __________.
Mesozoic
Which one of the following plants has thigmotropism?
Mimosa pudica
Which of the following is a correct statement about sugar movement in phloem?
Movement can occur both upward and downward in the plant.
A plant developed a mineral deficiency after being treated with a fungicide. What is the most probable cause of the deficiency?
Mycorrhizal fungi were killed.
The enzyme complex nitrogenase catalyzes the reaction that reduces atmospheric nitrogen to
NH3.
Plants can use nitrogen in the form of
NH4+ ion.
Which of the following soil minerals is most likely leached away during a hard rain?
NO3-
Which of the following, if used as a fertilizer, would be most immediately available for plant uptake?
NO3-
In angiosperms, each pollen grain produces two sperm. What do these sperm do?
One fertilizes an egg, and the other combines with two polar nuclei, which develop into stored food cells (endosperm).
In west Texas, cotton has become an important crop in the last several decades. However, in this hot, dry part of the country there is little rainfall, so farmers irrigate their cotton fields. They must also regularly fertilize the cotton fields because the soil is very sandy. the figure shows the record of annual productivity (measured in kilograms of cotton per hectare of land) since 1960 in a west Texas cotton field. Use these data to answer the following question. 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?
Plant a variety of cotton that requires less water and can tolerate salinity.
Select the correct statement about the life cycle of a fern.
Plant gametophytes are haploid multicellular bodies.
Select the best description of the significance of the meristems of plants.
Plant meristems are permanently embryonic regions within the plant body.
Which taxon is essentially equivalent to the "embryophytes"?
Plantae
How do plants obtain organic molecules?
Plants synthesize their own organic molecules.
The general biology class was divided into two groups. The first group of students was given 5 red bean seeds and 100 mL distilled water, and the second group received 5 red bean seeds and 100 mL 5% salt solution. Both teams immersed seeds in their respective solvents at the same time and left them for 24 hours. What do you expect to observe in seeds after 24 hours, and why?
Red beans in distilled water shrink due to water potential difference between the seeds and the water outside.
A parent with an S1S2 genotype exhibiting sporophytic self-incompatibility can potentially fertilize which of the following plant genotypes of the same species with pollen grains?
S3S4
Which of the following is a true statement?
Secondary growth is produced by both the vascular cambium and the cork cambium.
Which of the following statements about growth in plants is true?
Some plants lack secondary growth.
Ecologists often build models to depict the relationships between organisms. In such models, an arrow is used to link two organisms in a relationship. The arrowhead is next to the organism that is affected. If the effect is positive, the arrow is labeled with (+), and if negative, the label is (-).Capuchin monkeys have been known to use rocks to smash open the fruits of Brazil nut trees. On the rare occasions this has been observed, the monkeys consume all of the Brazil nuts. Thus, which of the following correctly depicts the relationship between capuchin monkeys and Brazil nut trees?
+ first then -
If ΨsΨs = 0.3 MPa and ΨsΨs = -0.45 MPa, the resulting ΨΨ is
-0.15 MPa.
The solute potential (Ψs)(Ψs) of pure water at sea level and at room temperature is
0.
An open beaker of pure water has a water potential
0.00 MPa.
This experiment suggests that the unknown amount of gibberellin in the experimental plant (B) is approximately
0.1 μμg/mL.
Imagine you are in an introductory biology laboratory observing the cross section of a primary dicot stem. The diameter of vascular bundle was 200 µm. Your instructor asked you to convert the diameter of the vascular bundle into mm. Which of the following is the correct response?
0.2
Please use the following information to answer the question below. Big Bend National Park in Texas is mostly Chihuahuan desert where rainfall averages about 10 inches per year. Yet when hiking in this bone-dry desert, it is not uncommon to encounter mosses and ferns. One such plant is called "flower of stone." It is not a flowering plant, nor does it produce seeds. Under arid conditions, its leaflike structures curl up. However, when it rains, it unfurls its leaves, which form a bright green rosette on the desert floor. Consequently, it is sometimes called the "resurrection plant." In which combination of locations would one who is searching for the gametophytes of flower of stone have the best chance of finding them?1. moist soil2. underground, nourished there by symbiotic fungi3. permanently shady places4. far from any flower of stone sporophytes
1 and 2 only
Which of the following were benefits to algae in the early oceans of Earth, compared to the first plants that colonized land?1. no scarcity of water2. less solar damage to tissues3. the need for structural support4. more plentiful dissolved carbon dioxide
1 and 2 only
The microsporidian Brachiola gambiae parasitizes the mosquito Anopheles gambiae. Adult female mosquitoes must take blood meals in order for their eggs to develop, and it is while they take blood that they transmit malarial parasites to humans. Male mosquitoes drink flower nectar. If humans are to safely and effectively use Brachiola gambiae as a biological control to reduce human deaths from malaria, then how many of the following statements should be true? 1. Brachiola should kill the mosquitoes before the malarial parasite they carry reaches maturity.2. Brachiola must be harmful to male mosquitoes but not to female mosquitoes.3. Microsporidians should infect mosquito larvae rather than mosquito adults.4. The subsequent decline in Anopheles gambiae should not significantly disrupt human food resources or other food webs
1 and 4 only
If the kingdom Plantae is someday expanded to include the charophytes, then the shared derived characteristics of the kingdom will include1. rings of cellulose-synthesizing complexes.2. chlorophylls a and b.3. alternation of generations.4. cell walls of cellulose.5. ability to synthesize sporopollenin.
1 and 5 only
What is thought to be the correct sequence of the following events during the Carboniferous period? 1. Vascular plants become more prevalent.2. Megaphylls with large surface areas become more prevalent.3. Atmospheric CO2 levels decline dramatically.4. Global cooling occurs, leading to widespread glaciations.
1, 2 ,3, 4
If intelligent extraterrestrials visited Earth 475 million years ago, and then again 300 million years ago (at the close of the Carboniferous period), what trends would they have noticed in Earth's terrestrial vegetation over this period? 1. a trend from dominant gametophytes to dominant sporophytes2. a trend from no true leaves to microphylls to megaphylls3. a trend from plants that grow just above the soil surface to "overtopping" plants4. a trend toward increased lignification of conducting systems
1, 2, 3, and 4
Part complete Please use the following information to answer the question below. The cycads, a mostly tropical phylum of gymnosperms, evolved about 300 million years ago and were dominant forms during the age of the dinosaurs. Though their sperm are flagellated, their ovules are pollinated by beetles. These beetles get nutrition (they eat pollen) and shelter from microsporophylls (leaflike structures that contain microsporangia). Upon visiting megasporophylls (leaflike structures where megaspores are formed), the beetles transfer pollen to the exposed ovules. In cycads, pollen cones and seed cones are borne on different plants. Cycads synthesize neurotoxins, especially in the seeds, that are effective against most animals, including humans. Which feature of cycads makes them similar to many angiosperms?1. They have exposed ovules.2. They have flagellated sperm.3. They are pollinated by animals.
3 only
Arrange the following in the correct sequence, from earliest to most recent, in which these plant traits originated.1. sporophyte dominance, gametophyte independence2. sporophyte dominance, gametophyte dependence3. gametophyte dominance, sporophyte dependence
3 →→ 1 →→ 2
Suppose that the cells of seed plants, like the skin cells of humans, produce a pigment upon increased exposure to UV radiation. Rank the following cells, from greatest to least, in terms of the likelihood of producing this pigment.1. cells of sporangium2. cells in the interior of a subterranean root3. epidermal cells of sporophyte megaphylls4. cells of a gametophyte
3, 1, 4, 2
In a typical dicot ovule, a surviving megaspore divided by ________ consecutive mitotic divisions without cytokinesis results in ________ nuclei.
3; 8
Within a gymnosperm megasporangium, what is the correct sequence in which the following should appear during development, assuming that fertilization occurs?1. sporophyte embryo2. female gametophyte3. egg cell4. megaspore
4 →→ 2 →→ 3 →→ 1
Arrange the following structures from largest to smallest, assuming that they belong to two generations of the same angiosperm.1. ovary2. ovule3. egg4. carpel
4, 1, 2, 3
Due to the limitation of land and water resources on planet earth, biotechnology can help to increase the crop yields to meet human needs and demands in the years to come. Farmers have to produce ________% more grain per hectare to feed human population in ________.
40; 2030
If a short-day plant has a critical night length of 15 hours, then which of the following 24-hour cycles will prevent flowering?
8 hours light/8 hours dark/light flash/8 hours dark
Typically, what percentage of a plant's fresh biomass is water?
80-90
You are conducting an experiment on plant growth. You take a plant fresh from the soil that weighs 5 kg. Then you dry the plant overnight and determine the dry weight to be 1 kg. Of this dry weight, how much would you expect to be made up of organic molecules?
960 g
Please use the following information to answer the question below. Fairy rings are circles of fungi that often appear in open meadows and in forest areas. In the soil beneath the fungi is an ever-extending mycelium. As the mycelium spreads to seek more food, it sometimes will produce the fungi we see above ground. The figure depicts the outline of a fairy ring that has appeared overnight in an open meadow, as viewed from above. The ring represents the farthest advance of this mycelium through the soil. Locations A−−D are all 0.5 meters below the soil surface. Which location is nearest to basidiocarps?
A
The following question refer to the diagram of an embryo sac of an angiosperm shown in the figure. Based on the figure, which cell(s) guide(s) the pollen tube to the egg cell?
A
Which of the following conclusions is supported by the research of both Frits Went and Charles and Francis Darwin on shoot responses to light?
A chemical substance involved in shoot bending is produced in shoot tips.
Which of these structures is a separate generation from the plant sporophyte?
A male gametophyte within a pollen grain
Which of the following occurs in an angiosperm ovule?
A megaspore mother cell (megasporocyte) undergoes meiosis.
Select the correct statement about plant growth.
A plant may produce juvenile and adult leaves at the same time
You are part of a desert plant research team trying to discover crops that will be productive in arid climates. You discover a plant that produces a hormone under water-deficit conditions that triggers a suite of drought responses. Most likely the hormone is
ABA.
If you wanted to increase the cation exchange and water retention capacity of loamy soil, what should you do?
Add clay to the soil.
A researcher has developed two stains for use with seed plants. One stains sporophyte tissue blue; the other stains gametophyte tissue red. If the researcher exposes pollen grains to both stains and then rinses away the excess stain, what will occur?
The pollen grains will have red interiors and blue exteriors.
If isolated plant cells with a water potential averaging -0.5 MPa are placed into a solution with a water potential of -0.3 MPa, which of the following would be the most likely outcome?
The pressure potential of the cells would increase.
What do fungi and arthropods have in common?
The protective coats of both groups are made of chitin.
Select the correct mechanism of stomatal opening and closing.
The radial orientation of cellulose microfibrils in the cell walls of guard cells causes them to bow outward and open the stomatal pore when turgid.
Why does overwatering a plant kill it?
The roots are deprived of oxygen.
In west Texas, cotton has become an important crop in the last several decades. However, in this hot, dry part of the country there is little rainfall, so farmers irrigate their cotton fields. They must also regularly fertilize the cotton fields because the soil is very sandy. the figure shows the record of annual productivity (measured in kilograms of cotton per hectare of land) since 1960 in a west Texas cotton field. Use these data to answer the following question. Based on the information provided in the figure, what is the most likely cause of the decline in productivity?
The soil water potential has become more negative due to salination.
Other than the transport of materials, what is another function that vascular tissue performs in a leaf?
The tissue functions as a skeleton that reinforces the shape of the leaf.
A plant cell is placed in distilled water, as shown in the figure. There is a net uptake of water by osmosis, causing the cell to become turgid. Select the correct statement about this setup, after the cell is fully turgid.
The water potentials (ΨΨ) of the cell and its surroundings are the same.
Which of the following best describes the ploidy level of a fertilized embryo sac?
There are haploid, diploid, and triploid cells.
In fungi, haploid hyphae fuse to produce dikaryotic and then diploid nuclei, only to restore the haploid condition by meiosis before the growth of new hyphae. What is the significance of a transient diploid state in fungi?
These sexual processes generate genetic variation.
Which of the following is a characteristic of hyphate fungi (fungi featuring hyphae)?
They are adapted for rapid directional growth to new food sources.
What is true of stamens, sepals, petals, and carpels?
They are modified leaves.
Which of the following statements about the cells shown in the photograph in the figure is true?
They are parenchyma cells and photosynthetic.
Which of the following statements about decomposers is true?
They break down waste products, leaf litter, and the bodies of dead organisms.
How do cells in a meristem differ from cells in other types of plant tissue?
They continue to divide.
________ is to xylem as ________ is to phloem.
Vessel element; sieve-tube member
Which of the following phenomena occurs naturally in plant cells?
Water (solvent) moves from regions of lower water potential to regions of higher solvent potential.
Select the accurate statement about water potential.
Water in a turgid cell has positive pressure potential.
What process is most important in the expansion of plant cells?
Water uptake
Which of the following is true of seedless vascular plants?
Whole forests were dominated by large, seedless vascular plants during the Carboniferous period.
If a plant's stomata are closed and no transpiration is occurring, which of the following predictions is accurate?
Without transpiration, less water will be absorbed from the soil.
Which of the following is a correct statement about a difference between xylem and phloem transport?
Xylem sap moves up; phloem sap moves up or down.
A biological cycle with a period of about 24 hours is called __________.
a circadian rhythm
Which of the following determines the direction of water movement across the membrane?
a difference in water potential
The following question refers to the generalized life cycle for land plants shown in the figure. What describes the product of when a zygote completes mitosis?
a diploid sporophyte
An action spectrum is best described as
a graph of the relative effectiveness of different wavelengths of radiation in driving a physiological process.
Which of the following can cause abnormal development of floral parts?
a mutation in a gene
Which of the following cell types retains the ability to undergo cell division?
a parenchyma cell 2 mm from the tip of a root
Iron deficiency is often indicated by yellowing in newly formed leaves. This suggests that iron is
a relatively immobile nutrient in plants.
A fellow student brought in a leaf to be examined. The leaf was dark green and thin, had stoma on the lower surface only, and had a total surface area of 10 square meters. What is the most likely environment where this leaf was growing?
a tropical rain forest
Which of the following characteristics helped seedless plants better adapt to life on land?
a well-developed vascular system
The following question refers to the generalized life cycle for land plants shown in the figure. In the figure, which structure produces haploid spores by meiosis?
Sporophyte
Select the correct statement contrasting gametophytes and sporophytes.
Sporophytes are diploid, whereas gametophytes are haploid.
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?
Sporophytes are parasites of gametophytes.
Which statement concerning grafting is correct?
Stocks provide root systems for grafting.
Which of the following processes happens during photosynthesis in plants?
Stomata open.
Several tomato plants are growing in a small garden plot. If soil water potential were to drop significantly on a hot summer afternoon, which of the following would most likely occur?
Stomatal apertures would decrease.
Select the correct statement about variation in stomatal density.
Stomatal density is developmentally plastic.
Which term below is the proposed kingdom that would include embryophytes and charophytes?
Streptophyta
Which one of the following statements about cell walls is true?
The plant cell wall prevents excessive uptake of water.
Which of the following plants is correctly matched with its fruit type?
beans−−simple
The initial response of the root cells of a tomato plant watered with seawater would be to
begin to plasmolyze as water is lost.
When an arborist prunes a limb off a valuable tree, he or she usually paints the cut surface. The primary purpose of the paint is to
block entry of pathogens through the wound.
A mature, unfertilized ovule in an angiosperm is the result of
both meiotic and mitotic divisions.
Which of the following elements is required for the stability of cell walls?
calcium
Which of the following gases in air circulating units inhibits the production of new ethylene in fruits?
carbon dioxide
The ovary is most often located on/in the
carpel.
The activation or inactivation of specific genes during cell differentiation depends largely on
cell division.
Most of the growth of a plant body is the result of __________.
cell elongation
The shoot elongation in a growing bud is due to
cell elongation localized in each internode.
Which of the following cellular structures is functionally important in cells of the gametophytes of both angiosperms and gymnosperms?
cell walls
Synthesis of which of the following compounds in a mature leaf would be least impacted by a temporary soil nitrogen deficiency?
cellulose
The most abundant organic compounds on planet Earth that are essential and a great resource to produce biofuels are
cellulose.
According to our current knowledge of plant evolution, which group of organisms should feature mitosis most similar to that of land plants?
charophytes
The closest algal relatives of land plants are __________.
charophytes
Which of these characteristics is shared by algae and seed plants?
chloroplasts
Which of the following is a symptom of magnesium deficiency in plants?
chlorosis
A corn (Zea mays) mutant is developed that is impaired in magnesium uptake. The most likely phenotypic expression would be
chlorosis, especially in the older leaves.
The following question(s) refer to the phylogenetic trees. In phylogenetic tree I, which group of organisms is most directly related to the common ancestor of the tree?
chytrids
The products of asexual reproduction in plants are
clones, and they do not require the fusion of egg and sperm.
Which of the following plant seeds disperse by water?
coconut
The embryo of a grass seed is enclosed by two protective sheaths, a ________, which covers the young shoot, and a(n) ________, which covers the young root.
coleoptile; coleorhiza
Which of the following have unevenly thickened primary walls that support young, growing parts of the plant and provide flexibility?
collenchyma cells
Fossil fungi date back to the origin and early evolution of plants. What combination of environmental and morphological change is similar in the evolution of both fungi and plants?
colonization of land and loss of flagellated cells
Mineral nutrients __________.
contribute little to a plant's overall mass
Nitrogen-fixing bacteria in the soil __________.
convert atmospheric nitrogen to ammonia
Nitrogen fixation is a process that
converts nitrogen gas into ammonia.
As the epidermis is pushed outward and sloughed off, it is replaced by tissues produced by the __________.
cork cambium
Which of the following is correctly matched with its tissue system?
cortex ... ground tissue system
Several million people around the world experience malnutrition or hunger due to lack of nutritious food. Which tool would be most effective in helping alleviate human malnutrition and hunger?
crop breeding
When growing plants in culture, IAA is used to stimulate cell enlargement. Which plant growth regulator has to now be added to stimulate cell division?
cytokinin
The proton pump __________.
uses the energy stored in ATP to produce a hydrogen ion gradient across membranes.
Some xerophytes minimize water loss by __________.
using the CAM pathway
Movement of xylem sap from roots to leaves __________.
usually depends on tension, or negative pressure potential Submit
The cork cambium replaces which of the following tissues during the plant growth?
vascular cambium
Ignoring all other factors, what kind of day would result in the fastest delivery of water and minerals to the leaves of a tree?
warm, dry day
In both lichens and mycorrhizae, what does the fungal partner provide to its photosynthetic partner?
water and minerals
The cuticle on the surface of epidermis of leaves is an adaptation for plants to conserve
water.
You are hiking in a forest and come upon a mysterious plant, which you believe to be a lycophyte or a monilophyte. Which of the following would be most helpful in determining the correct classification of the plant?
whether it has microphylls or megaphylls
Which of the following types of plants are incapable of self-pollination?
dioecious
Which association below is correct?
dioecious ... separate female and male plants
Immediately after karyogamy occurs, which term applies?
diploid
The conspicuous part of a fern plant is a _____.
diploid sporophyte
When you look at a pine or maple tree, the plant you see is a __________.
diploid sporophyte
Which of the following is a characteristic of all angiosperms?
double internal fertilization
Which of the following would have had gene sequences most similar to the charophyte that was the common ancestor of the land plants?
early bryophytes
During the process of etiolation, a morphological adaptation in potato plant growth, which of the following activities takes place?
elongated stems
Some dioecious species have the XY genotype for male and XX for female. After double fertilization, what would be the genotypes of the embryos and endosperm nuclei?
embryo XX/endosperm XXX or embryo XY/endosperm XXY Submit
In which of the following pairs are the two terms equivalent?
embryo sac−−female gametophyte
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?
embryos
The innermost layer of the root cortex is the __________.
endodermis
Which of the following refers to symbiotic relationships that involve fungi living between the cells in plant leaves?
endophytes
Which of the following is an advantage of asexual reproduction in plants?
enhanced survival of genetically favorable offspring
Guard cells of stomata in leaves of plants are modified
epidermal cells.
Root hairs, which absorb the water and minerals in the majority of plants, are the extensions of root
epidermal cells.
Root hairs originate from which of the following parts of the root?
epidermis
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?
ethylene
In an experiment, a plant physiologist has four groups of bananas of the same species. He exposes each of the four groups of bananas with the same concentration of auxins, gibberellins, abscisic acid, or ethylene. Which of these four groups of bananas ripen the fastest?
ethylene
The ripening of fruit and the dropping of leaves and fruit are principally controlled by
ethylene
Which plant hormone affects the response to mechanical stress, senescence, leaf abscission, and fruit ripening?
ethylene
What is the main force by which most of the water within xylem vessels moves toward the top of a tree?
evaporation of water through stoma
The water lost during transpiration is a side effect of the plant's exchange of gases. However, the plant derives some benefit from this water loss in the form of
evaporative cooling and mineral transport.
Which of the following treatments would enhance the level of the Pfr form of phytochrome?
exposure to red light
All of the following are involved in movement of sucrose into the phloem in most plants except __________.
facilitated diffusion
A botanist discovers a plant that lacks the ability to form starch grains in root cells, yet the roots still grow downward. This evidence refutes the long-standing hypothesis that
falling statoliths trigger gravitropism.
Compared with a cell with few aquaporin proteins in its membrane, a cell containing many aquaporin proteins will have a __________.
faster rate of osmosis
Compared to a cell with few aquaporins in its membrane, a cell containing many aquaporins will have a
faster rate of osmosis.
In pine, the embryo develops within the __________.
female gametophyte
In gymnosperms, megaspores develop into __________.
female gametophytes
Which of the following sex and generation combinations most directly produces the fruit?
female sporophyte
Which of the following sex and generation combinations most directly produces the integument of a pine seed?
female sporophyte
Which of the following sex and generation combinations most directly produces the megasporangium of pine ovules?
female sporophyte
Which group is noted for the independence of gametophyte and sporophyte generations from each other?
ferns
During the Carboniferous period, forests consisting mainly of __________ produced vast quantities of organic matter, which was buried and later became coal.
ferns and other seedless plants
If humans had been present to build house structures during the Carboniferous period, which plant types would have been possible building materials?
ferns, horsetails, and lycophytes
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
ferns.
Rhizobia, actinomycetes, and cyanobacteria all share the common feature that they can
fix atmospheric nitrogen.
Angiosperms are different from all other plants because only they have __________.
flowers
Two unique reproductive adaptations of angiosperms are
flowers and fruits.
The three characteristics of all angiosperms are
flowers, double fertilization, and fruits.
The primary function of the integument of an ovule is to
form a seed coat.
At the end of meiosis (without cytokinesis), a diploid cell in a dicot flower ovule produce
four unidentical haploid nuclei.
Auxin transports from cell to cell
from top to bottom.
Angiosperms are the most successful terrestrial plants. Which of the following features is unique to them and helps account for their success?
fruits enclosing seeds
When a mycelium infiltrates an unexploited source of dead organic matter, what are most likely to appear within the food source soon thereafter?
fungal enzymes
When pathogenic fungi are found growing on the roots of grape vines, grape farmers sometimes respond by covering the ground around their vines with plastic sheeting and pumping a gaseous fungicide into the soil. The most important concern of grape farmers who engage in this practice should be that the
fungicide might also kill mycorrhizae.
The diploid phase of the life cycle is shortest in which of the following?
fungus
Which of the following is an example of sexual reproduction?
fusion of sperm and egg nuclei in an ovule
In the process of evolution, ________ in the life cycle became reduced in size and completely dependent on ________ for nutrients.
gametophyte; sporophyte
Which of the following stages in the development of a male gametophyte is haploid (n)?
generative cell
The application of which of the following hormones would be a logical first choice in an attempt to produce normal growth in mutant dwarf plants?
gibberellin
Which of the following plant hormones plays a critical role in breaking seed dormancy?
gibberellin
Young leaves and developing seeds are the prime sites for ________ synthesis.
gibberellin
If a farmer wanted more loosely packed clusters of grapes, he would most likely spray the immature bunches with
gibberellins.
Statoliths are structures that are responsible for
gravitropism.
A class of 10 students was divided into two groups. The first group was given a rose leaf, and the second group was given a cactus. Which of these two groups identified the xerophyte based on which characteristic feature(s)?
group 2; thick cuticle
Sporophylls can be found in which of the following?
gymnosperms
Please use the following information to answer the question below. Diploid nuclei of the ascomycete Neurospora crassa contain 14 chromosomes. A single diploid cell in an ascus will undergo one round of meiosis, followed in each of the daughter cells by one round of mitosis, producing a total of eight ascospores. What is the ploidy of a single mature ascospore?
haploid
The following question refers to the generalized life cycle for land plants shown in the figure. Meiosis, as part of the alternation of generations in land plants, produces
haploid spores.
"Golden Rice"__________.
has a modified genome that includes transgenes that lead to an increase in vitamin A content
Axillary buds
have dormant meristematic cells.
A flash of red light followed by a flash of far-red light given during the middle of the night to a short-day plant will likely
have no effect upon flowering.
Gymnosperms differ from both extinct and extant (living) ferns because they
have pollen.
The primary growth of a plant adds __________ and secondary growth adds __________.
height ... girth
Guard cells do which of the following?
help balance the photosynthesis-transpiration compromise
An important example of interaction between fungi and certain other organisms is mycorrhizae, in which the fungal partners __________.
help plants take up nutrients and water
Self-incompatibility __________.
helps maintain genetic variability in a population
All fungi are __________.
heterotrophic
Which of the following environmental conditions would favor high stomatal density during leaf development in plants?
high light exposure
The strength and hardness of wood are due to
highly lignified walls of xylem.
What is the greatest threat to plant diversity?
human population growth
Which of the following ions plays a critical role in transport and cotransport processes in plant cells?
hydrogen
The cohesiveness of water molecules is due to
hydrogen bonds between water molecules.
Stomatal movement (opening and closing) depends on active transport of
hydrogen ions.
The body of most fungi consists of threadlike __________, which form a network called a __________.
hyphae ... mycelium Submit
Here is the ABC hypothesis of the impact of genes A, B, and C on floral part development:i. "A" genes are switched on in the two outer whorls (sepals and petals).ii. "B" genes are switched on in the two middle whorls (petals and stamens).iii. "C" genes are switched on in the inner two whorls (stamens and carpels).Which of these genes are active for petals?
i and ii
Arrange the following in the correct sequence of steps in nitrogen fixation.i. Nitrogen gasii. Nitrite ioniii. Ammoniaiv. Nitrate ion
i, iii, ii, iv
Arrange the following stages in the life cycle of an angiosperm in a correct sequence.i. gametophyte developmentii. double fertilizationiii. pollinationiv. seed development
i, iii, ii, iv
Arrange the following tissues in an order from the upper surface to the middle area of a leaf cross section.i. epidermisii. xylemiii. palisade mesophylliv. spongy mesophyll
i, iii, iv, ii
The following question is based on parts of a growing primary root.i. root capii. zone of elongationiii. zone of cell divisioniv. zone of cell differentiationv. apical meristemWhich of the following is the correct sequence from the growing tips of the root upward?
i, v, iii, ii, iv
A plant will recognize a pathogenic invader
if it has the specific R gene that corresponds to the pathogen molecule encoded by an Avr gene.
A plant has a set of multiple alleles for "self" gene "S," which causes self-incompatibility (the ability of plant to reject its own pollen or pollen from closely related plants) to fertilize the egg. Here is a set of plants (sporophytes) with genotypes:i. S1S2ii. S2S3iii. S3S3iv. S1S3The S3 pollen from S2S3 parental sporophyte cannot fertilize the eggs of
ii
Arrange the following steps of cell differentiation during plant growth (in length) in the correct sequence.i. cell division in primary meristemii. cell division in apical meristemiii. differentiated cellsiv. growing cells in primary meristem
ii, i, iv, iii
Arrange the following tissues, organs, chemicals, and flows in the correct cyclical steps in the bulk flow of phloem sap.i. sieve tubeii. xylem vesseliii. sucrose in leaf (source)iv. sucrose in root (sink)v. bulk flow by negative pressurevi. bulk flow by positive pressure
iii, i, vi, iv, ii, v
Generally, wind pollination is most likely to be found in seed plants that grow
in dense, single-species stands.
Root hairs are important to a plant because they __________.
increase the surface area for absorption
Mitotic activity by the apical meristem of a root makes which of the following more possible?
increased absorption of mineral nutrients
Historically, the decrease in stomatal density in many plant species could be related to
increased levels of oxygen.
Most scientists agree that global warming is under way; thus, it is important to know how plants respond to heat stress. Which of the following would be a useful line of inquiry to try to improve plant response to and survival of heat stress?
increased production of heat-shock proteins
Which of the following could be considered an evolutionary advantage of asexual reproduction in plants?
increased success of progeny in a stable environment
In extremely cold regions, woody species may survive freezing temperatures by
increasing cytoplasmic levels of specific solute concentrations, such as sugars.
Which of the following tissues played a very critical role in the process of evolution to produce the great biodiversity of flowering plant species?
lateral meristem
Secondary growth in eudicot stems and roots is caused by the
lateral meristem.
The secondary growth in stems and roots of woody plants produced by the
lateral meristem.
Which of the plant organs pays a pivotal role on dissipating heat?
leaf
Which plant organ detects changes in the photoperiod and produces signaling molecules that cue buds to develop as flowers?
leaf
Which of the following has the lowest (most negative) water potential?
leaf air spaces
One important difference between the anatomy of roots and the anatomy of leaves is that
leaves have mesophyll tissue, but roots do not.
The rise (upward mobility/transportation) of xylem sap by the cohesion-tension mechanism begins at the
leaves.
The size of clay particles ranges from ________ in diameter.
less than 0.002 m
Which of the following environmental factors plays a critical role in plant photosynthesis?
light and CO2
Charles and Francis Darwin discovered that __________.
light is perceived by the tips of coleoptiles
What evolutionary development allowed plants to grow tall?
lignified vascular tissue
Please use the following information to answer the question below. A biology student hiking in a forest happens upon an erect, 15-cm-tall plant that bears microphylls and a strobilus (a cone) at its tallest point. When disturbed, the cone emits a dense cloud of brownish dust. The student takes the dust back to the laboratory, where a microscope reveals the dust to be composed of tiny spheres with a high oil content. A dissection of the interior of this organism's stem should reveal
lignified vascular tissues.
The characteristic feature of typical collenchyma tissue is
lignin filled intercellular spaces.
More than a quarter of the dry wood mass contributed by ________, a strengthening polymer, comes from the cell walls of ________ tissue.
lignin; sclerenchyma
Transgenic plants (plants modified by biotechnology tools) are
likely to increase soil erosion.
A plant cell placed in a solution with a lower (more negative) water potential will __________.
lose water and plasmolyze
Most of the water taken up by a plant is
lost during transpiration.
Please use the following information to answer the question below. A biology student hiking in a forest happens upon an erect, 15-cm-tall plant that bears microphylls and a strobilus (a cone) at its tallest point. When disturbed, the cone emits a dense cloud of brownish dust. The student takes the dust back to the laboratory, where a microscope reveals the dust to be composed of tiny spheres with a high oil content. This student has probably found a(n)
lycophyte sporophyte.
What is the role of proton pumps in root hair cells?
maintain the H+ gradient
The most common natural cytokine is zeatin, and it was first discovered in
maize.
Which of the following sex and generation combinations most directly produces the pollen tube?
male gametophyte
Which of the following is considered an organic fertilizer?
manure
A fruit is a __________.
mature ovary
Plants must always compromise between __________ and __________.
maximizing photosynthesis ... minimizing water loss
Where does meiosis occur in a flowering plant?
megasporocyte and microsporocyte
Which of the following is the correct sequence of processes that takes place when a flowering plant reproduces?
meiosis →→ pollination →→ nuclear fusion →→ formation of embryo and endosperm
Which tissue is responsible for plant growth?
meristem
The hypersensitive response, a nonspecific defense mechanism, of plants prevents the spread of pathogens by producing ________ around the infection site.
methyl salicylic acid
A short-day plant exposed to nights longer than the minimum for flowering but interrupted by short flashes of light
might flower depending upon the wavelengths of the light flashes.
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
minerals.
Which of the following was an essential adaptive feature for the evolution of plants from water to the land?
minimizing the evaporative loss of water
In mosses gametes are produced by _____; in ferns gametes are produced by _____.
mitosis ... mitosis
The following question refers to the generalized life cycle for land plants shown in the figure. In the figure, which processes may result in haploid structures during the generalized life cycle for land plants?
mitosis and meiosis
The relationship between legumes and Rhizobium is __________.
mutualistic
Mycorrhizae are __________.
mutualistic associations between plant roots and fungi
Which of the following is an adaptation that enhances the uptake of water and minerals by roots?
mycorrhizae
An example of a mutualistic association between a plant and a fungus would be
mycorrhizae.
The transpiration pull is due to the ________ that causes water to move up through the xylem that begins at the surface of mesophyll cells.
negative pressure potential
A short-day plant will flower only when
nights are longer than a certain critical value.
Given that early land plants most likely share a common ancestor with green algae, the earliest land plants were most likely
nonvascular plants that grew leafless photosynthetic shoots above the shallow fresh water in which they lived.
Which of the following "vegetables" is botanically a fruit?
okra
Where do fern antheridia develop?
on the underside of the gametophyte
In asexual reproduction,
one parent passes copies of all of its genes to its offspring without the fusion of gametes.
Double fertilization means that __________.
one sperm is needed to fertilize the egg, and a second sperm is needed to fertilize the polar nuclei
Which of the following seedlings will probably bend toward light?
one whose tip is separated from its base by a gelatin block
The diffusion of free water across a selectively permeable membrane is called
osmosis.
Using the figure, which of the following taxonomic groups from the list below would you expect to have a genome with DNA sequences most similar to the Plantae?
other charophytes
Which of the following flower parts develops into the pulp of a fleshy fruit?
ovary
A seed develops from an __________.
ovule
Which of the following flower parts develops into a seed?
ovule
Which structure is common to both gymnosperms and angiosperms?
ovule
Seeds develop from
ovules.
Which of the following macronutrients plays a critical role on plant growth and crop yields?
oxygen
In a root nodule, the gene coding for nitrogenase is
part of the Rhizobium genome.
The lateral root originates in which of the following parts of the root?
pericycle
Which of the following root tissues gives rise to lateral roots?
pericycle
Unlike most angiosperms, grasses are pollinated by wind. As a consequence, some unnecessary parts of grass flowers have almost disappeared. Which of the following parts would you expect to be most reduced in a grass flower?
petals
If the range of a species of plants expands to a higher latitude, which of the following processes is the most likely to be modified by natural selection?
photoperiodic response
Which of the following processes allowed land plants to structurally adapt shoots to acquire light from sun and carbon dioxide from the air?
photosynthesis
Trichomes on certain plant species are a ________ to prevent excessive herbivory.
physical defense
Which chemical compounds are produced by a plant in response to a pathogen invasion?
phytoalexins and salicylic acid
Which of the following chemicals functions as a photoreceptor in plants and regulates photoperiodism and responses to seasons?
phytochromes
Which of the following is a multiple fruit?
pineapple
A leaf would best be described as a
plant organ.
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
plants evolved alternation of generations independently of green algae.
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?
plants that do not produce abscisic acid and have a short, thick taproot
What are epiphytes?
plants that grow on other plants but do not obtain nutrients from their hosts
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 best supports this view?
plasmodesmata
The symplast is the continuum of cytosol connected by
plasmodesmata
In addition to seeds, which of the following characteristics is unique to the seed-producing plants?
pollen
The colonization of dry land environments by seed plants was made possible by the evolution of __________.
pollen
Which of the following can be found in gymnosperms?
pollen
Please use the following information to answer the question below. Oviparous (egg-laying) animals have internal fertilization (sperm cells encounter eggs within the female's body). Yolk and/or albumen is (are) provided to the embryo, and a shell is then deposited around the embryo and its food source. Eggs are subsequently deposited in an environment that promotes their further development or are incubated by one or both parents. The internal fertilization that occurs in animals prior to shell deposition is analogous to which features of an angiosperm?
pollen tube and sperm nuclei
Which of the following are structures of angiosperm gametophytes?
pollen tubes
A person working with plants may increase the lateral branches by which of the following?
pruning shoot tips
Which of the following would be least likely to affect osmosis in plants?
receptor proteins in the membrane
The signaling molecule for flowering might be released earlier than usual in a long-day plant exposed to flashes of __________.
red light during the night
Copper plays a critical role in ________ of plant cells.
redox reactions and lignin-biosynthetic enzymes
The functional role of sporopollenin is primarily to
reduce the dehydration of zygotes.
The introduction of genes using biotechnological techniques (genetic engineering) from the bacterium Bacillus thuringiensis in corn and cotton crops
reduces the use of chemical insecticides.
Plant biotechnology is an effective tool for
reducing world hunger.
Which one of the following is a response in plants to a water deficit?
reduction in the rate of transpiration
Cellular differentiation and morphogenesis in plants depend primarily on __________.
regulation of gene expression
Essential elements are those
required by living organisms to complete their life cycle and reproduce.
Storage roots, stems, and leaves are some of the evolutionary adaptations of plants. Which of the following are listed in the order of modified root, stem, and leaf?
rhizome, stolon, tendril
You are studying a plant from the Amazon rain forest that shows strong self-incompatibility. To characterize this reproductive mechanism, you would look for
ribonuclease (RNAase) activity in stigma cells.
Which plant pollen grain has one opening?
rice
Cassava is a ________ crop that has been modified by biotechnology experiments.
root
The ________ is (are) the first plant organ(s) that emerge(s) during the process of seed germination.
root
Which of the following plant structures shares the most common features and functions with a fungal hyphae?
root hairs
Which of the following would NOT be seen in a cross section through the woody part of a root?
root hairs
Which part of a plant absorbs most of the water and minerals taken up from the soil?
root hairs
You are most likely to see guttation in small plants when the
root pressure exceeds transpiration pull.
Mycorrhizal associations are symbiotic interactions between __________ and __________.
root systems ... soil fungi
Which part of the plant structure synthesizes cytokinins primarily?
roots
Fungi of the clade Ascomycetes are recognized on the basis of their production of __________ during sexual reproduction.
saclike structures
The transduction pathway that activates systemic acquired resistance in plants is initially signaled by
salicylic acid.
A student examining leaf cross sections under a microscope finds many tightly packed cells with relatively thick cell walls. The cells have no nucleus and are dead. What type of cells are they?
sclerenchyma
Heartwood and sapwood consist of __________.
secondary xylem
Which of the following cells in a dicot stem is only one cell thick?
secondary xylem Submit
The vascular rays, made of parenchyma, connect the
secondary xylem and phloem.
Vascular cambium in eudicot stems produce
secondary xylem and phloem.
Annual rings in woody plant stems and roots represent the
secondary xylem of spring and summer.
The dominant type of tissue that makes up most of the wood of a tree is
secondary xylem.
Seed packets give a recommended planting depth for the enclosed seeds. The most likely reason some seeds are to be covered with only 1/4 inch of soil is that the
seeds require light to germinate.
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 the farmer to achieve such a goal?
selecting crops adapted to arid areas
Auxins are produced mainly in
shoot tips
Plants that have their flowering inhibited by being exposed to bright lights at night are
short-day plants.
The results of this experiment, shown on the left of the graph in the figure (area A), may be used to
show a correlation between plant height and gibberellin concentration.
Phloem sap flows through
sieve tubes.
Plant hormones act by directly affecting the activities of __________.
signal transduction pathways
The amount of water lost through the stomata of a leaf under the same environmental conditions depends on the
size and shape of guard cells in a unit area.
The pollen produced by wind-pollinated plants is often smaller than the pollen produced by animal-pollinated plants. A reason for this might be that __________.
small pollen grains can be carried farther by the wind
The term second messengers refers to
small, water-soluble, non-protein molecules produced or released intracellularly during signal transduction.
Adventitious roots in monocots are very helpful in coastal ecosystems to reduce
soil erosion.
According to the pressure flow hypothesis of phloem transport,
solute moves from a high concentration in the source to a lower concentration in the sink.
Cellular differentiation is responsible for __________.
some epidermal cells in Arabidopsis becoming root hairs while other epidermal cells do not
Which of the following male reproductive organs in a dicot flower is haploid (n)?
sperm cell
Gas exchange, which is necessary for photosynthesis, can occur most easily in which leaf tissue?
spongy mesophyll
A botanist discovers a new species of land plant with a dominant sporophyte, chlorophylls a and b, and cell walls made of cellulose. In assigning this plant to a phylum, which of the following, if present, would be least useful?
spores
At the conclusion of meiosis in plants, the end products are always four haploid
spores.
In contrast to bryophytes, in vascular plants the dominant stage of the life cycle is the __________.
sporophyte
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.
sugars; leaf; apical meristem
An association between the roots of a terrestrial plant with soil fungus is referred to as
symbiosis.
When plants exhibit generalized defense responses in organs distant from the infection site, this is termed
systemic acquired resistance.
The following are characteristics of plant cells but not animal cells except
the absence of mitochondria.
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,
the annual rings, new xylem, vascular cambium, phloem, and bark.
Biofuels are mainly produced by
the breakdown of cell wall biopolymers into sugars that can be fermented.
Which of the following traits was most important in enabling the first plants to move onto land?
the development of sporopollenin to prevent the desiccation of zygotes
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?
the endodermis
The cortex in a cross section of a dicot root is located between
the epidermis and endodermis.
What drives the flow of water through the xylem?
the evaporation of water from the leaves
Please use the following information to answer the question below. The cycads, a mostly tropical phylum of gymnosperms, evolved about 300 million years ago and were dominant forms during the age of the dinosaurs. Though their sperm are flagellated, their ovules are pollinated by beetles. These beetles get nutrition (they eat pollen) and shelter from microsporophylls (leaflike structures that contain microsporangia). Upon visiting megasporophylls (leaflike structures where megaspores are formed), the beetles transfer pollen to the exposed ovules. In cycads, pollen cones and seed cones are borne on different plants. Cycads synthesize neurotoxins, especially in the seeds, that are effective against most animals, including humans. If the beetles survive by consuming cycad pollen, then whether the beetles should be considered mutualists with, or parasites of, the cycads depends upon
the extent to which their overall activities affect cycad reproduction.
During the process of evolution of an angiosperm,
the gametophyte became reduced, smaller, simpler, and short lived.
Two groups of tomatoes were grown in the laboratory, one with humus added to the soil and the other a control without humus. The leaves of the plants grown without humus were yellowish (less green) compared with those of the plants grown in humus-enriched soil. The best explanation for this difference is that __________.
the humus contained minerals such as magnesium and iron, needed for the synthesis of chlorophyll
Please use the following information to answer the question below. For several decades now, amphibian species worldwide have been in decline. A significant proportion of the decline seems to be due to the spread of the chytrid fungus Batrachochytrium dendrobatidis (Bd). Chytrid sporangia reside within the epidermal cells of infected animals, animals that consequently show areas of sloughed skin. Infected animals can also be lethargic, which is expressed through failure to hide and failure to flee. The infection cycle typically takes four to five days, at the end of which zoospores are released from sporangia into the environment. Zoospores are spores of fungi (as well as some algae and protozoans) that use a flagella for swimming locomotion. In some amphibian species, mortality rates approach 100%; other species seem able to survive the infection. A researcher took water in which a Janthinobacterium lividum (Jl) population had been thriving, filtered the water to remove all bacterial cells, and then applied the water to the skins of adult amphibians to see if there would subsequently be a reduced infection rate by Bd when frog skins were inoculated with Bd. For which of the following hypotheses is this procedure a potential test?
the hypothesis that a toxin secreted by Jl cells kills Bd cells when both are present together on frog skin
Which structure or compartment is part of the symplast?
the interior of a vessel element
Most plants flower when __________.
the nights are the right length
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
the normal symbiotic fungi are not present in the sterilized soil and water and mineral uptake is faster when mycorrhizae are present.
Recent research has shown that fertilization requires that carpels recognize pollen grains as "self" or "non-self." For self-incompatibility, the system requires
the rejection of self cells.
Upregulation of leghemoglobin biosynthesis in a leguminous species would most likely indicate
the successful inoculation of nitrogen-fixing bacteria.
The imbibition in seeds takes place during seed germination because of
the uptake of water due to the low water potential of the dry seed.
In nature, poinsettias bloom in early March. Research has shown that the flowering process is triggered 3 months before blooming occurs. In order to make poinsettias bloom in December, florists change the length of the light/dark cycle in September. Given this information and clues, which of the following is a correct statement about poinsettias?
they are short-day plants.
Three mitotic divisions within the female gametophyte of a flowering plant will produce
three antipodal cells, two polar nuclei, one egg, and two synergids.
Charles and Francis Darwin concluded from their experiments on phototropism by grass seedlings that the part of the seedling that detects the direction of light is the
tip of the coleoptile.
What is the probable role of salicylic acid in the defense responses of plants?
to activate the systemic acquired resistance of plants
In hydroponic culture, what is the purpose of bubbling air into the solute?
to provide oxygen to the root cells
Thigmotropism is a movement in response to __________.
touch
Which one of the following refers to the loss of water through the stomata in a plant's leaves?
transpiration
Xylem, a vascular tissue, performs which of the following functions?
transport of water and minerals
Which of the following best explains both the growth of a vine up the trunk of a tree and the directional growth of a houseplant toward a window?
tropism response
The union of a sperm cell with ________ of the female gametophyte is referred as double fertilization.
two polar nuclei
In flowering plants, a mature male gametophyte contains
two sperm nuclei and one tube cell nucleus.
Phloem sap in plant vascular system flows
two ways from the leaves to the sites of sugar use and to the sugar storage units.
The Pr form of the phytochrome pigment has maximum absorption in the __________ part of the spectrum.
ultraviolet
Callus is a group of
undifferentiated cells.
The function of antipodals in an embryosac is
unknown.
The adaptive advantage associated with the filamentous nature of fungal mycelia is primarily related to __________.
an extensive surface area well suited for invasive growth and absorptive nutrition
As a youngster, you drive a nail in the trunk of a young pine tree that is 3 meters tall. The nail is about 1.5 meters from the ground. Fifteen years later, you return and discover that the tree has grown to a height of 20 meters. About how many meters above the ground is the nail?
1.5
Please use the following information to answer the question below. Diploid nuclei of the ascomycete Neurospora crassa contain 14 chromosomes. A single diploid cell in an ascus will undergo one round of meiosis, followed in each of the daughter cells by one round of mitosis, producing a total of eight ascospores. If a single, diploid G2 nucleus in an ascus contains 400 nanograms (ng) of DNA, then a single ascospore nucleus of this species should contain how much DNA (ng), carried on how many chromosomes?
100, carried on 7 chromosomes Submit
If a long-day plant has a critical night length of 9 hours, which 24-hour cycle would prevent flowering?
14 hours light/10 hours dark
Please use the following information to answer the question below. In onions (Allium), cells of the sporophyte have 16 chromosomes within each nucleus. How many chromosomes should be in a megasporangium nucleus?
16
Please use the following information to answer the question below. In onions (Allium), cells of the sporophyte have 16 chromosomes within each nucleus. How many chromosomes should be in an embryo nucleus?
16
Please use the following information to answer the question below. Big Bend National Park in Texas is mostly Chihuahuan desert where rainfall averages about 10 inches per year. Yet when hiking in this bone-dry desert, it is not uncommon to encounter mosses and ferns. One such plant is called "flower of stone." It is not a flowering plant, nor does it produce seeds. Under arid conditions, its leaflike structures curl up. However, when it rains, it unfurls its leaves, which form a bright green rosette on the desert floor. Consequently, it is sometimes called the "resurrection plant." Upon closer inspection of the leaves of flower of stone, one can observe tiny, cone-like structures. Each cone-like structure emits spores of two different sizes. Further investigation also reveals that the roots of flower of stone branch only at the growing tip of the root, forming a Y-shaped structure. Consequently, flower of stone should be expected to possess which other characteristics?1. a gametophyte generation that is dominant2. lignified vascular tissues3. microphylls4. spores that are diploid when mature
2 and 3 only
Please use the following information to answer the question below. The cycads, a mostly tropical phylum of gymnosperms, evolved about 300 million years ago and were dominant forms during the age of the dinosaurs. Though their sperm are flagellated, their ovules are pollinated by beetles. These beetles get nutrition (they eat pollen) and shelter from microsporophylls (leaflike structures that contain microsporangia). Upon visiting megasporophylls (leaflike structures where megaspores are formed), the beetles transfer pollen to the exposed ovules. In cycads, pollen cones and seed cones are borne on different plants. Cycads synthesize neurotoxins, especially in the seeds, that are effective against most animals, including humans. Which feature of cycads distinguishes them from most other gymnosperms?1. They have exposed ovules.2. They have flagellated sperm.3. They are pollinated by animals.
2 and 3 only
What is true of the phylogenetic tree in the figure? 1. It depicts uncertainty about whether the bryophytes or the vascular plants evolved first.2. It is hypothetical.3. It shows that ferns are the closest living relatives to the seed plants.4. It indicates that seeds are a shared ancestral character of all vascular plants.
2 only
Arrange the following terms from most inclusive to least inclusive.1. embryophytes2. green plants3. seedless vascular plants4. ferns
2, 1, 3, 4
Atmospheric nitrogen can be fixed by nitrogen-fixing bacteria. Arrange the following forms of nitrogen from the atmospheric N stage to the final form that enters the roots.1. Ammonia2. Nitrogen gas3. Ammonium ion4. Nitrite5. Nitrate
2, 1, 3, 4, 5
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. spores2. sporophytes3. sporangia
2, 3, 1
Arrange the following five events in an order that explains the mass flow of materials in the phloem.1. Water diffuses into the sieve tubes.2. Leaf cells produce sugar by photosynthesis.3. Solutes are actively transported into sieve tubes.4. Sugar is transported from cell to cell in the leaf.5. Sugar moves down the stem.
2, 4, 3, 1, 5
Part complete Please use the following information to answer the question below. For several decades now, amphibian species worldwide have been in decline. A significant proportion of the decline seems to be due to the spread of the chytrid fungus Batrachochytrium dendrobatidis (Bd). Chytrid sporangia reside within the epidermal cells of infected animals, animals that consequently show areas of sloughed skin. Infected animals can also be lethargic, which is expressed through failure to hide and failure to flee. The infection cycle typically takes four to five days, at the end of which zoospores are released from sporangia into the environment. Zoospores are spores of fungi (as well as some algae and protozoans) that use a flagella for swimming locomotion. In some amphibian species, mortality rates approach 100%; other species seem able to survive the infection. The chytrid sporangia reside within the amphibian epidermal cells. Consequently, which term(s) apply to Bd?
2, 4, and 5 only
A fertilizer marked "20-10-5" is
20% N (as ammonium nitrate), 10% P (as phosphate), and 5% K (as the mineral potash).
What adaptations should one expect of the seed coats of angiosperm species whose seeds are dispersed by frugivorous (fruit-eating) animals, as opposed to angiosperm species whose seeds are dispersed by other means?1. The exterior of the seed coat should have barbs or hooks.2. The seed coat should contain secondary compounds that irritate the lining of the animal's mouth.3. The seed coat should be able to withstand low pH environments.4. The seed coat, upon its complete digestion, should provide vitamins or nutrients to animals.5. The seed coat should be resistant to the animals' digestive enzymes.
3 and 5 only
The opening of stomata is thought to involve
an increase in the solute concentration of the guard cells.
Human survival literally depends on the produce of __________.
angiosperms
Among the organisms listed here, which are thought to be the closest relatives of fungi?
animals
Ten tomato plants are germinated and maintained in a large tray with no drainage. After several weeks they all begin to wilt and die despite repeated watering and fertilization. The most likely cause of this die-off is
anoxia.
Meiosis will produce microspores in the __________.
anther
Which of the following floral parts is correctly matched?
anther−−microsporangia
Which of the following is correctly paired with its life cycle generation?
anther−−sporophyte
When a diploid cell in the ovule develops into a seed without sexual reproduction, it is referred to as
apomixis.
You are weeding your garden when you accidentally expose some roots of your pea plants. You notice swellings (root nodules) on the roots, and there is a reddish tinge to the ones you accidentally damaged. Most likely your pea plants
are benefiting from a mutualistic bacterium.
Plants often use changes in day length (photoperiod) to trigger events such as dormancy and flowering. It is logical that plants have evolved this mechanism because photoperiod changes
are more predictable than air temperature changes.
The apical bud of a shoot produces ________, resulting in the inhibition of lateral bud growth.
auxin
Which of the following plant hormones alters gene expression and causes cells in the zone of elongation to produce proteins quickly?
auxin
Which of the following plant hormones is responsible for the activation of lateral buds to grow into new branches?
auxin
Which of the following plant hormones stimulates cell elongation?
auxin
Experiments on the positive phototropic response of plants indicate that
auxin can move to the shady side of the stem
After some time, the tip of a plant that has been forced into a horizontal position grows upward. This phenomenon is related to
auxin movement toward the lower side of the stem.
The proton pump plays a critical role on cell growth response by increasing cell wall plasticity to
auxin.
Lateral branches, thorns, or flowers on the shoot and vertical roots on the rhizome produce from the
axillary bud.
The germination of seeds __________.
depends on imbibition
For an element to be considered a macronutrient, __________.
it must be required in relatively large amounts
The sundew plant has to digest insects because __________.
it obtains nitrogen from their bodies that it cannot get from the soil
Which process occurs in fungi and has the opposite effect on a cell's chromosome number than does meiosis?
karyogamy
What sexual processes in fungi generate genetic variation?
karyogamy and meiosis
Most bryophytes, such as mosses, differ from all other plants in that they __________.
lack true leaves and roots
Please use the following information to answer the question below. For several decades now, amphibian species worldwide have been in decline. A significant proportion of the decline seems to be due to the spread of the chytrid fungus Batrachochytrium dendrobatidis (Bd). Chytrid sporangia reside within the epidermal cells of infected animals, animals that consequently show areas of sloughed skin. Infected animals can also be lethargic, which is expressed through failure to hide and failure to flee. The infection cycle typically takes four to five days, at the end of which zoospores are released from sporangia into the environment. Zoospores are spores of fungi (as well as some algae and protozoans) that use a flagella for swimming locomotion. In some amphibian species, mortality rates approach 100%; other species seem able to survive the infection. Sexual reproduction has not been observed in Bd. A Bd sporangium initially contains a single haploid cell. Which of the following processes must be involved in generating the multiple zoospores eventually produced by each sporangium?1. S phase2. cytokinesis3. mitosis4. meiosis
1, 2, and 3 only
Which trait(s) is (are) shared by many modern gymnosperms and angiosperms?1. pollen transported by wind2. lignified xylem3. microscopic gametophytes4. endosperm
1, 2, and 3 only
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 tissues2. decreasing dehydration of leaf tissues3. countering the effect of declining CO2 on photosynthesis4. reinforcing the effect of declining CO2 on photosynthesis5. decreasing the O2 content of air next to the leaves lower than it would otherwise be6. increasing the O2 content of air next to the leaves higher than it would otherwise be
1, 3, and 6 only
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).1. sporophyte2. microspores3. microsporangia4. pollen cone5. pollen nuclei
1, 4, 3, 2, 5
Maximum amount of water loss occurs through stomata that account for ________% of the external leaf surface area.
1-2
Part complete Please use the following information to answer the question below. The cycads, a mostly tropical phylum of gymnosperms, evolved about 300 million years ago and were dominant forms during the age of the dinosaurs. Though their sperm are flagellated, their ovules are pollinated by beetles. These beetles get nutrition (they eat pollen) and shelter from microsporophylls (leaflike structures that contain microsporangia). Upon visiting megasporophylls (leaflike structures where megaspores are formed), the beetles transfer pollen to the exposed ovules. In cycads, pollen cones and seed cones are borne on different plants. Cycads synthesize neurotoxins, especially in the seeds, that are effective against most animals, including humans. On the Pacific island of Guam, large herbivorous bats called "flying foxes" commonly feed on cycad seeds, a potent source of neurotoxins. The flying foxes do not visit male cones. Consequently, what should be true?
Flying foxes can be dispersal agents of cycad seeds when they swallow the seeds whole (without getting chewed).
Which of the following is a difference between plants and fungi?
Fungi are heterotrophic, and plants are autotrophic
The following question refers to the generalized life cycle for land plants shown in the figure. In the figure, which structure produces haploid gametes by mitosis?
Gametophyte
Almost all of the members of this clade form arbuscular mycorrhizae in a mutualistic partnership with plants.
Glomeromycetes
Most of the dry weight of a plant is derived from
H2O and CO2.
The heavy line in the figure illustrates the relationship between auxin concentration and cell growth in stem tissues. If the same range of concentrations were applied to lateral buds, what curve(s) would probably be produced?
I
Challenges for survival of the first land plants includeI. sources of water.II. sperm transfer.III. desiccation.IV. animal predation.V. lack of structural support.
I, II, III, and V only
Please use the following information to answer the question below. For several decades now, amphibian species worldwide have been in decline. A significant proportion of the decline seems to be due to the spread of the chytrid fungus Batrachochytrium dendrobatidis (Bd). Chytrid sporangia reside within the epidermal cells of infected animals, animals that consequently show areas of sloughed skin. Infected animals can also be lethargic, which is expressed through failure to hide and failure to flee. The infection cycle typically takes four to five days, at the end of which zoospores are released from sporangia into the environment. Zoospores are spores of fungi (as well as some algae and protozoans) that use a flagella for swimming locomotion. In some amphibian species, mortality rates approach 100%; other species seem able to survive the infection. The fact that infection by Bd causes lethargy in many infected amphibians can have what effect on efforts to accurately census the numbers of dead or dying amphibians at a particular time, in a particular habitat?I. It can cause underestimation due to infected amphibians preferring to seek out refuges relative to uninfected amphibians.II. It can cause underestimation due to increased predation on, and removal of, infected amphibians relative to uninfected amphibians.III. It can cause overestimation because infected frogs should be more readily observable to human census-takers than should uninfected amphibians.
I, II, and III
The vegetative (nutritionally active) bodies of most fungi areI. composed of hyphae.II. referred to as a mycelium.III. usually underground.
I, II, and III
Please use the following information to answer the question below. For several decades now, amphibian species worldwide have been in decline. A significant proportion of the decline seems to be due to the spread of the chytrid fungus Batrachochytrium dendrobatidis (Bd). Chytrid sporangia reside within the epidermal cells of infected animals, animals that consequently show areas of sloughed skin. Infected animals can also be lethargic, which is expressed through failure to hide and failure to flee. The infection cycle typically takes four to five days, at the end of which zoospores are released from sporangia into the environment. Zoospores are spores of fungi (as well as some algae and protozoans) that use a flagella for swimming locomotion. In some amphibian species, mortality rates approach 100%; other species seem able to survive the infection. When adult amphibian skin harbors populations of the bacterium Janthinobacterium lividum (Jl), chytrid infection seems to be inhibited. Which of the following represents the best experimental design for conclusively determining whether this inhibition is real?
Take infected amphibians, and assign them to two populations. Leave one population alone; inoculate the other with Jl. Measure the rate at which infection proceeds in both populations
Which of the following is one possible advantage of biofuels versus oil?
The CO2 produced by biofuels will be absorbed by the crops used to produce them, creating a carbon-neutral cycle.
Which of the following events suggests there is a change in the egg cell membrane after penetration by a sperm?
The Ca2+ concentration increases in the cytoplasm of the egg.
Why are axillary buds often inhibited from growing even though a stem may be actively elongating?
The cells of axillary buds respond differently to auxin than stem cells.
Which of these facts provides the best support for the hypothesis that plants evolved from green algae?
The chloroplasts of plants and green algae all have both chlorophyll a and b.
Which of the following is true concerning flowering plants?
The flower includes sporophyte tissue.
When a plant is attacked by a pathogen, it may respond by carrying out a defense that causes cell and tissue death near the infection site, restricting the spread of the pathogen. What is the name of this defense?
The hypersensitive response
The hormone that helps plants respond to drought is __________.
abscisic acid
Which of the following plant hormones plays a critical role on stomatal closures to avoid wilting?
abscisic acid
Which of these plant hormones is not typically considered a growth-promoting substance?
abscisic acid
Fungi obtain nutrients through __________.
absorption
The earliest vascular plants on land had underground stems (rhizomes) but no roots. Water and mineral nutrients were most likely obtained by
absorption by mycorrhizae.
Auxin enhances cell elongation in all of these ways EXCEPT __________.
acid-induced denaturation of cell wall proteins
Which of the following would be the most effective strategy to remove toxic heavy metals from a soil?
adding plant species that have the ability to take up and accumulate heavy metals
Please use the following information to answer the question below. For several decades now, amphibian species worldwide have been in decline. A significant proportion of the decline seems to be due to the spread of the chytrid fungus Batrachochytrium dendrobatidis (Bd). Chytrid sporangia reside within the epidermal cells of infected animals, animals that consequently show areas of sloughed skin. Infected animals can also be lethargic, which is expressed through failure to hide and failure to flee. The infection cycle typically takes four to five days, at the end of which zoospores are released from sporangia into the environment. Zoospores are spores of fungi (as well as some algae and protozoans) that use a flagella for swimming locomotion. In some amphibian species, mortality rates approach 100%; other species seem able to survive the infection. If infection primarily involves the outermost layers of adult amphibian skin, and if the chytrids use the skin as their sole source of nutrition, then which term best applies to the chytrids?
aerobic chemoheterotroph
Please use the following information to answer the question below. The Brazil nut tree, Bertholletia excels (n = 17), is native to tropical rain forests of South America. It is a hardwood tree that can grow to over 50 meters tall, is a source of high-quality lumber, and is a favorite nesting site for harpy eagles. As the rainy season ends, tough-walled fruits, each containing 8−−25 seeds (Brazil nuts), fall to the forest floor. Brazil nuts are composed primarily of endosperm. About $50 million worth of nuts are harvested each year. Scientists have discovered that the pale yellow flowers of Brazil nut trees cannot fertilize themselves and admit only female orchid bees as pollinators. The agouti (Dasyprocta spp.), a cat-sized rodent, is the only animal with teeth strong enough to crack the hard wall of Brazil nut fruits. It typically eats some of the seeds, buries others, and leaves still others inside the fruit, which moisture can then enter. The uneaten seeds may subsequently germinate. People who attempted to plant Brazil nuts in hopes of establishing plantations of Brazil nut trees played roles most similar to those of
agoutis.
Hyphae form a covering over roots. These hyphae create a large surface area that helps to do which of the following?
aid in absorbing minerals and ions
Ecologists often build models to depict the relationships between organisms. In such models, an arrow is used to link two organisms in a relationship. The arrowhead is next to the organism that is affected. If the effect is positive, the arrow is labeled with (+), and if negative, the label is (-). Which of the following models best illustrates the relationship of the Brazil nut tree and the other organisms associated with it?
all +'s 1 -
Which of the following arise, directly or indirectly, from meristematic activity?
all of the choices listed
Plant hormones produce their effects by
altering the expression of genes and modifying the permeability of the plasma membrane.
The term alternation of generations refers to the
alternation of gametophytes and sporophytes in the life cycle of plants.
Which of the following characteristics of plants is ABSENT in their closest relatives, the charophyte algae?
alternation of generations
The aleurone layer is stimulated to release ________ as a result of gibberellin release from the embryo.
amylase
The black dots that cover strawberries are actually individual fruits from a flower with multiple carpels. The fleshy and tasty portion of a strawberry derives from the receptacle of the flower. Therefore, a strawberry is both __________.
an aggregate fruit and an accessory fruit
A fruit that develops from many separate carpels of one flower is referred as
an aggregate fruit.
Please use the following information to answer the question below. The Brazil nut tree, Bertholletia excels (n = 17), is native to tropical rain forests of South America. It is a hardwood tree that can grow to over 50 meters tall, is a source of high-quality lumber, and is a favorite nesting site for harpy eagles. As the rainy season ends, tough-walled fruits, each containing 8−−25 seeds (Brazil nuts), fall to the forest floor. Brazil nuts are composed primarily of endosperm. About $50 million worth of nuts are harvested each year. Scientists have discovered that the pale yellow flowers of Brazil nut trees cannot fertilize themselves and admit only female orchid bees as pollinators. The agouti (Dasyprocta spp.), a cat-sized rodent, is the only animal with teeth strong enough to crack the hard wall of Brazil nut fruits. It typically eats some of the seeds, buries others, and leaves still others inside the fruit, which moisture can then enter. The uneaten seeds may subsequently germinate. Orchid bees are to Brazil nut trees as ________ are to pine trees.
breezes
In which of the following plant groups does the mature sporophyte depend completely on the gametophyte for nutrition?
bryophytes
Seedless plants include __________.
bryophytes, lycophytes, and monilophytes
Which of the following plant organs is an evolutionary adaptation of a leaf that stores food?
bulb
The water and minerals in the xylem vessels transported by
bulk flow.
If you were to prune the shoot tips of a plant, what would be the effect on the plant and the leaf area index?
bushier plants; higher leaf area indexes
How have fruits contributed to the success of angiosperms?
by facilitating dispersal of seeds
Humus consists of __________.
decomposing organic material
Please use the following information to answer the question below. The Brazil nut tree, Bertholletia excels (n = 17), is native to tropical rain forests of South America. It is a hardwood tree that can grow to over 50 meters tall, is a source of high-quality lumber, and is a favorite nesting site for harpy eagles. As the rainy season ends, tough-walled fruits, each containing 8−−25 seeds (Brazil nuts), fall to the forest floor. Brazil nuts are composed primarily of endosperm. About $50 million worth of nuts are harvested each year. Scientists have discovered that the pale yellow flowers of Brazil nut trees cannot fertilize themselves and admit only female orchid bees as pollinators. The agouti (Dasyprocta spp.), a cat-sized rodent, is the only animal with teeth strong enough to crack the hard wall of Brazil nut fruits. It typically eats some of the seeds, buries others, and leaves still others inside the fruit, which moisture can then enter. The uneaten seeds may subsequently germinate. The harpy eagle, Harpia harpyja, is the largest, most powerful raptor in the Americas. It nests only in trees taller than 25 meters. It is a "sloth specialist" but will also kill agouti. Thus, if these eagles capture too many agoutis from a particular locale, they might contribute to their own demise by
increasing habitat loss.
Which of the following experimental procedures would most likely reduce transpiration while allowing the normal growth of a plant?
increasing the level of carbon dioxide around the plant
The pattern of leaf arrangement on the shoots of land plants is critical for
increasing the rate of photosynthesis.
Compared to most animals, the growth of most plants is best described as
indeterminate.
Which of the following hormones would be most useful in promoting the rooting of plant cuttings?
indolebutyric acid
Which of the following is most important in making the typical seed more resistant to adverse conditions than the typical spore?
integument(s)
Please use the following information to answer the question below. Oviparous (egg-laying) animals have internal fertilization (sperm cells encounter eggs within the female's body). Yolk and/or albumen is (are) provided to the embryo, and a shell is then deposited around the embryo and its food source. Eggs are subsequently deposited in an environment that promotes their further development or are incubated by one or both parents. The shell of an animal egg is analogous to which feature of an angiosperm?
integuments
Which structure protects seed plants' embryos from desiccation?
integuments
Which of the following most correctly describes the effect of most hormones that control growth and development?
interaction between hormones
Which tissue is responsible for the recovery and rapid growth of damaged leaves of grass grazed by sheep in a pasture?
intercalary meristem
Which type of meristem enables grasses to regrow after grazing by herbivores?
intercalary meristem
Which example below is a concern related to the debate over plant biotechnology?
introduced genes spreading into related wild species and leading to the creation of "superweeds"
Topsoil __________.
is a mixture of rock fragments, living organisms, and humus
Please use the following information to answer the question below. The Brazil nut tree, Bertholletia excels (n = 17), is native to tropical rain forests of South America. It is a hardwood tree that can grow to over 50 meters tall, is a source of high-quality lumber, and is a favorite nesting site for harpy eagles. As the rainy season ends, tough-walled fruits, each containing 8−−25 seeds (Brazil nuts), fall to the forest floor. Brazil nuts are composed primarily of endosperm. About $50 million worth of nuts are harvested each year. Scientists have discovered that the pale yellow flowers of Brazil nut trees cannot fertilize themselves and admit only female orchid bees as pollinators. The agouti (Dasyprocta spp.), a cat-sized rodent, is the only animal with teeth strong enough to crack the hard wall of Brazil nut fruits. It typically eats some of the seeds, buries others, and leaves still others inside the fruit, which moisture can then enter. The uneaten seeds may subsequently germinate. Entrepreneurs attempted, but failed, to harvest nuts from plantations grown in Southeast Asia. Attempts to grow Brazil nut trees in South American plantations also failed. In both cases, the trees grew vigorously, produced healthy flowers in profusion, but set no fruit. Consequently, what is the likely source of the problem?
pollination failure
Statoliths are responsible for plants to exhibit
positive gravitropism.
What would enhance water uptake by a plant cell?
positive pressure on the surrounding solution
Which of the following elemental ions plays a critical role in opening and closing of stomata?
potassium
The rapid leaf movements resulting from a response to touch (thigmotropism) primarily involve
potassium channels.
Stomata open when the flow of
potassium ions in guard cells increases from neighboring epidermal cells across the cell membrane.
The major difference between angiosperms and gymnosperms comes from the __________.
presence or absence of a protective covering over the ovule
Which of the following responses is the correct order of tissues from the center to the periphery (outside) of a two-year-old dicot stem cross section?
primary xylem, secondary xylem, vascular cambium, secondary phloem, secondary xylem
Essential elements are the elements that are required for a plant to
produce another generation.
Plants contain meristems whose major function is to
produce more cells.
The diploid generation of the plant life cycle always __________.
produces spores
Which of the following is the most likely plant response to an attack by herbivores?
production of chemical compounds for defense or to attract predators
If all fungi in an environment that perform decomposition were to suddenly die, then which group of organisms should benefit most, after their fungal competitors have been removed?
prokaryotes
Almost all plant cells have the ability to produce abscisic acid. One of the functions of abscisic acid in plants is to
promote stomatal closure during drought stress.
Which type of roots support tall and top-heavy plants?
prop roots
The seed coat's most important function is to provide
protection for the embryo.
Please use the following information to answer the question below. The Brazil nut tree, Bertholletia excels (n = 17), is native to tropical rain forests of South America. It is a hardwood tree that can grow to over 50 meters tall, is a source of high-quality lumber, and is a favorite nesting site for harpy eagles. As the rainy season ends, tough-walled fruits, each containing 8−−25 seeds (Brazil nuts), fall to the forest floor. Brazil nuts are composed primarily of endosperm. About $50 million worth of nuts are harvested each year. Scientists have discovered that the pale yellow flowers of Brazil nut trees cannot fertilize themselves and admit only female orchid bees as pollinators. The agouti (Dasyprocta spp.), a cat-sized rodent, is the only animal with teeth strong enough to crack the hard wall of Brazil nut fruits. It typically eats some of the seeds, buries others, and leaves still others inside the fruit, which moisture can then enter. The uneaten seeds may subsequently germinate. The agouti is most directly involved with the Brazil nut tree's dispersal of
sporophyte embryos.
Which of the following is the correct sequence during the alternation of generations in the life cycle in a flowering plant?
sporophyte →→ meiosis →→ gametophyte →→ gametes →→ fertilization →→ diploid zygote
In seed plants, which of the following is part of a pollen grain and has a function most like that of the seed coat?
sporopollenin
The structural integrity of bacteria is to peptidoglycan as the structural integrity of plant spores is to
sporopollenin.
Microsporangia in flowering plants are located in the
stamen.
A plant mutant that showed normal gravitropic bending but did not store starch in its plastids would require a reevaluation of the role of __________ in gravitropism.
statoliths
The vascular bundle in the shape of a single central cylinder in a root is called the
stele
Gibberellins and auxins play a common role in
stem elongation.
Active transport would be least important in the normal functioning of which of the following plant tissue types?
stem tracheid element
In which plant cell or tissue would the pressure component of water potential most often be negative?
stem xylem
In grafting, the plant that provides the root system is the __________ and the twig is the __________.
stock ... scion
CO2 enters the inner spaces of the leaf through the
stoma
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?
stomata
Photosynthesis begins to decline when leaves wilt because
stomata close, restricting CO2 entry into the leaf.
Mature cork cells deposit a waxy substance called ________ in cell walls.
suberin
Which of the following is an adaptation in xerophytes?
succulent stems with thick cuticle
The dominant chemical in phloem sap is (are)
sucrose.
The solute most abundant in phloem sap is __________.
sugar
Please use the following information to answer the question below. The Brazil nut tree, Bertholletia excels (n = 17), is native to tropical rain forests of South America. It is a hardwood tree that can grow to over 50 meters tall, is a source of high-quality lumber, and is a favorite nesting site for harpy eagles. As the rainy season ends, tough-walled fruits, each containing 8−−25 seeds (Brazil nuts), fall to the forest floor. Brazil nuts are composed primarily of endosperm. About $50 million worth of nuts are harvested each year. Scientists have discovered that the pale yellow flowers of Brazil nut trees cannot fertilize themselves and admit only female orchid bees as pollinators. The agouti (Dasyprocta spp.), a cat-sized rodent, is the only animal with teeth strong enough to crack the hard wall of Brazil nut fruits. It typically eats some of the seeds, buries others, and leaves still others inside the fruit, which moisture can then enter. The uneaten seeds may subsequently germinate. The same bees that pollinate the flowers of the Brazil nut trees pollinate orchids, which are epiphytes (plants that grow on other plants); however, orchids cannot grow on Brazil nut trees. These observations explain
why Brazil nut trees do not set fruit in areas where only orchids are grown and harvested
A small flower with green petals is most likely __________.
wind-pollinated
Which of the following pollinating agents is correctly matched with the type of plant it helps pollinate?
wind−−grasses
A plant has the following characteristics: a taproot system, several growth rings evident in a cross section of the stem, and a layer of bark around the outside. Which of the following best describes the plant?
woody eudicot
Which of the following tissues have revolutionized the advancement of vascular plants with extensive shoot and root systems on land in the process of evolution?
xylem
Cell division in the vascular cambium adds to the girth of a tree by adding new __________ to the layer's interior and __________ to the layer's exterior.
xylem ... phloem
Which of the following is an adaptation by plants to life on land?
xylem tracheids and vessels
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
xylem.
A plant cell with a ψS of -0.65 MPa maintains a constant volume when bathed in a solution that has a ψS of -0.30 MPa and is in an open container. The cell has a __________.
ψP of +0.35 MPa