BLY 122 Pre-Class Assignments Chpts 25, 26, 27, 29, 30, 31, 32

Which of the following is responsible for the evolutionary success of eukaryotes? A) All of these choices are correct. B) possessing a dynamic endomembrane system C) possessing a dynamic cytoskeleton D) localizing where energy metabolism takes place E) having complex patterns of gene regulation

A) All of these choices are correct.

If cyanobacteria never evolved during Earth's history, how would their absence affect the composition of Earth's atmosphere? A) There would be less oxygen in the atmosphere. B) There would be less methane in the atmosphere. C) There would be less carbon in the atmosphere. D) There would be less hydrogen in the atmosphere. E) There would be less nitrogen in the atmosphere.

A) There would be less oxygen in the atmosphere.

Antibiotics can kill _____ in the human body, which may sometimes lead to health problems such as inflammatory bowel disease. A) both harmful and beneficial bacteria B) fungi C) beneficial bacteria D) archaeons E) harmful bacteria

A) both harmful and beneficial bacteria

Which of the following organisms is currently one of the MOST important photosynthetic organisms in the oceans? A) diatoms B) red algae C) green algae D) glaucocystophytes E) None of the answer options is correct.

A) diatoms

Photosynthesis _____ the atmosphere, whereas respiration _____ the atmosphere. A) removes CO2 from; introduces CO2 to B) introduces CO2 to; removes CO2 from

A) removes CO2 from; introduces CO2 to

Archaea and Bacteria are involved in which of the following cycles? (Select all that apply.) A) the sulfur cycle B) the carbon cycle C) the nitrogen cycle

A) the sulfur cycle B) the carbon cycle C) the nitrogen cycle

Photosynthesis and respiration affect atmospheric CO2 levels on a _____ timescale, whereas volcanic eruptions affect atmospheric CO2 levels on a _____ timescale. A) yearly; century B) century; yearly

A) yearly; century

Seeds are composed of: haploid tissues of the gametophyte. All of these choices are correct. diploid tissues of the embryo. diploid tissues of the ovule-bearing sporophyte.

All of these choices are correct.

Which of the following plants were present on Earth 100 million years ago? cycads conifers All of these choices are correct. angiosperms ferns and horsetails

All of these choices are correct.

How do pathogens enter into plant tissues? through the stomata on the piercing mouthparts of insects feeding on the plants All these choices are correct. by secreting enzymes that weaken epidermal cells through wounds or damaged tissues

All these choices are correct

Which statements are likely to have been TRUE of the earliest angiosperms? (Select all that apply.) Animal pollination made possible by flowers allowed them to survive at low density in tropical forest understories. The presence of vessels allowed them to form a tall, emergent layer in tropical forests. They evolved in shady and wet conditions, growing toward the side to exploit light gaps in the canopy overhead. The evolutionary innovation of flowers allowed them to be much more diverse than other seed plants radiating at this time.

Animal pollination made possible by flowers allowed them to survive at low density in tropical forest understories. They evolved in shady and wet conditions, growing toward the side to exploit light gaps in the canopy overhead.

Bacteria or archaeons can be which of the following types of organisms? A) chemoheterotrophs B) All of these choices are correct. C) photoheterotrophs D) chemoautotrophs E) photoautotrophs

B) All of these choices are correct.

How do cattle digest complex plant polysaccharides like cellulose? A) Mechanical forces of cud-chewing break the cell walls of plant fibers, enabling the cattle to extract the digestible contents of the cells. B) Bacterial populations in one of the four compartments of their stomachs are able to break the bonds between adjacent glucose units of cellulose. C) Acids produced in the stomach degrade cellulose. D) They have specialized mammalian enzymes to degrade the bonds of cellulose.

B) Bacterial populations in one of the four compartments of their stomachs are able to break the bonds between adjacent glucose units of cellulose.

_____ effectively limits how large a bacterium can grow. The bigger the bacterial cell, the less likely it is that nutrients can reach the cell's interior. A) Differentiation B) Diffusion C) Transduction D) Conjugation

B) Diffusion

Over the last several decades, what have researchers discovered about atmospheric CO2 levels? A) They increased for a period, but have now stabilized. B) They have increased. C) They have remained the same. D) They have decreased.

B) They have increased.

Which of the following best describes a symbiotic relationship between two organisms? A) Two organisms live in close, physical association with each other where both organisms thrive, but one is the primary provider and the other is the primary beneficiary. B) Two organisms live in close, long-term, physical association with each other. C) Two organisms live in close, physical association with each other where both organisms benefit from the relationship. D) Two organisms live in close, physical association with each other where one organism benefits to the detriment of the other.

B) Two organisms live in close, long-term, physical association with each other.

Nitrogen gas (N2) in the atmosphere can be DIRECTLY utilized by which of the following organisms? A) archaeons B) both bacteria and archaeons C) algae D) bacteria E) eukaryotes

B) both bacteria and archaeons

Green algae are most closely related to: A) diatoms. B) land plants. C) brown algae. D) red algae.

B) land plants.

The _____ cycle deals with geological processes and carbon reservoirs, some of which have been built up (or take place) over a period of millennia. In contrast, the _____ cycle involves biological processes that are carried out on a daily and/or seasonal basis. A) short-term carbon; long-term carbon B) long-term carbon; short-term carbon C)short-term carbon; rapid carbon D) long-term carbon; intermediate carbon

B) long-term carbon; short-term carbon

The rate of respiration _____ throughout the year. A) varies significantly B) remains more or less constant

B) remains more or less constant

Which of the following processes is responsible for the changes scientists observed in atmospheric concentrations of 12C, 13C, and 14C over the last 200 years? A) subduction B) the burning of fossil fuels C) chemical weathering D) volcanism E) the clearing of forests

B) the burning of fossil fuels

How do eukaryotic cells generate and maintain genetic diversity? A) through horizontal gene transfer B) through sexual reproduction C) through asexual reproduction D) by allowing more mutations

B) through sexual reproduction

pathogens obtain resources from living cells, whereas _____ pathogens kill cells before colonizing them. Necrotrophic; biotrophic All fungi; all bacterial All bacterial; all fungi Biotrophic; necrotrophic

Biotrophic; necrotrophic

Which of the following is an important consequence of the evolution of diatoms and coccolithophorids? A) They produced respective "blooms" in the ocean. B) They dominated photosynthesis in the oceans. C) The silica and calcium carbonate contained in these organisms became a primary source of sediments on the deep seafloor. D) None of the answer options is correct. E) They led to the extinction of cyanobacteria.

C) The silica and calcium carbonate contained in these organisms became a primary source of sediments on the deep seafloor.

_____ is a type of horizontal gene transfer during which genetic information is transferred from one bacterium to another by a virus. A) Transferation B) Conduction C) Transduction D) Conjugation E) Transformation

C) Transduction

Many euryarchaeote and crenarchaeote archaeons are _____, or organisms that thrive in high-temperature environments (some in temperatures as high as 122°C). A) hypothermophiles B) halophiles C) hyperthermophiles D) basophiles E) nonhalophiles F) acidophiles

C) hyperthermophiles

Photosynthesis and respiration both play a major role in the _____ carbon cycle, and can affect atmospheric CO2 levels on a seasonal or annual basis. A) long-term B) None of the answer options is correct. C) short-term

C) short-term

Which of the following processes INCREASES the amount of CO2 in the atmosphere? (Select all that apply.) A) chemical weathering B) photosynthesis C) volcanic eruptions D) subduction E) respiration

C) volcanic eruptions E) respiration

Oxygen is used during a reaction if the process is: A) anoxygenic. B) oxygenic. C) anaerobic. D) aerobic.

D) aerobic.

All of the membranes of the eukaryotic cell are in dynamic continuity except for membranes in the: A) nuclear membrane. B) Golgi apparatus. C) endoplasmic reticulum. D) mitochondria and chloroplasts.

D) mitochondria and chloroplasts.

Recall that in the northern hemisphere, atmospheric CO2 levels are highest in early spring and lowest in early fall. What accounts for this seasonal fluctuation in atmospheric CO2 levels? A) human activities B) respiration C) biomineralization D) photosynthesis E) plate tectonics

D) photosynthesis

Chloroplasts are thought to have evolved from: A) mitochondria. B) proteobacteria. C) autotrophic protists. D) algae. E) cyanobacteria.

E) cyanobacteria.

Chloroplasts and mitochondria in eukaryotes are thought to have originated by _____, wherein one organism lives inside another. A) phagocytosis B) antagonism C) partial symbiosis D) parasitism E) endosymbiosis

E) endosymbiosis

are chemical signaling molecules that influence physiology and development. Lipids Hormones Meristems Mitochondria Genes

Hormones

Which of the following statements accurately describes the role of insects in early angiosperm evolution? Insect pollination may have allowed early angiosperms to thrive in the canopy of tropical rain forests. Mammal pollination may have contributed to early angiosperm success. Insect pollination may have allowed early angiosperms to thrive in the understory habitats of tropical rain forests. Insects did not play a significant role in early angiosperm evolution. Very few living members of the earliest angiosperm groups produce flowers that are visited by insects.

Insect pollination may have allowed early angiosperms to thrive in the understory habitats of tropical rain forests.

Why is air a much more challenging medium for dispersal than water? (Select all that apply.) It has a lower heat capacity and thus is a poor temperature buffer. It is more turbulent. It provides less protection from UV radiation. It tends to dry out living tissues. It is less dense, so objects have less buoyancy. It is less dense, so it offers less mechanical support.

It has a lower heat capacity and thus is a poor temperature buffer. It provides less protection from UV radiation. It tends to dry out living tissues. It is less dense, so objects have less buoyancy.

If plant life was never subjected to herbivores/predators, how would plant diversity be affected? Plant life would likely be less diverse. Plant diversity would remain unchanged. Plant life would likely be more diverse.

Plant life would likely be less diverse.

Which of the following statements is TRUE regarding secondary growth in vascular plants? (Select all that apply.) Secondary growth depends only on the vascular cambium. Secondary growth causes a plant to grow in diameter (not height). Secondary growth depends on both the vascular and cork cambia. Secondary growth causes a plant to grow in height (not diameter). Secondary growth depends only on the cork cambium.

Secondary growth causes a plant to grow in diameter (not height). Secondary growth depends on both the vascular and cork cambia.

What are the components of the Janzen-Connell hypothesis? (Select all that apply.) Seeds from common plants will have a higher survival rate. Seeds located far away from the parent will have a higher survival rate. Seeds located close to plants of the parent will have a higher survival rate. Seeds from rare plants will have a higher survival rate.

Seeds located far away from the parent will have a higher survival rate. Seeds from rare plants will have a higher survival rate.

A farmer has adopted a new program of integrative pest management. What will this program entail for the farmer and his crops? (Select all that apply.) The farmer will assess which pests are consuming his crops. The farmer will use industrial pesticides as a first line of defense. The farmer will introduce natural predators for the pests. The farmer will use industrial pesticides as a last line of defense.

The farmer will assess which pests are consuming his crops. The farmer will introduce natural predators for the pests. The farmer will use industrial pesticides as a last line of defense.

As trees get larger and the number of leaves increases, transpiration rates rise and demand for water increases. How do mature plant stems meet this added demand for water? Cells of the xylem continue to divide and produce more cells that transport water. Cells present in the pith closest to the xylem differentiate into xylem cells. Vascular cambium continues to divide, and cells of its inner surface differentiate to form additional secondary xylem cells. Cells of secondary phloem adjacent to the vascular cambium differentiate into xylem cells.

Vascular cambium continues to divide, and cells of its inner surface differentiate to form additional secondary xylem cells.

A houseplant is growing on your windowsill. Every Sunday, without fail, your roommate turns the plant 180 degrees. When you ask your roommate why she does that, her reply is simply, "I want straight plants." Does this method produce straight plants? No. The auxins don't respond to turning, only to light. Yes. Rotating the plant redistributes the statoliths, so they remain in the bottom of each cell. No. The statoliths in the plant cells do not respond to turning; the plant will grow straight whether or not your roommate turns the plant. Yes. Rotating the plant will even out the growth of the plant toward the light by changing where the light hits the plant every week.

Yes. Rotating the plant will even out the growth of the plant toward the light by changing where the light hits the plant every week.

Nikolai Vavilov's principle was that the places where the wild relatives of crop plants are most diverse are also likely to be: (Select all that apply.) a source of cultivars that will produce higher yields than current commercial cultivars. a source of genetic variation that may be useful for breeding programs. the best places to grow domesticated crops. the places where the crops were first domesticated.

a source of genetic variation that may be useful for breeding programs. the places where the crops were first domesticated.

Nitrogen-bearing compounds that affect animal nervous systems and are often bitter tasting belong to which class of compounds? latex alkaloids phenols proteins terpenoids

alkaloids

Which of the following defensive compounds produced by plants can harm an herbivore's nervous system? terpenes tannins alkaloids phenols

alkaloids

Recall that in many plants, if the shoot apical meristem is removed, axillary buds become active and new lateral branches form. What is this an example of? meristem dominance auxin dominance apical dominance axillary dominance

apical dominance

The condition in which shoot apical meristems suppress the growth of axillary buds is called: shoot-root ratio. primary growth. repression. optimum growth pattern. apical dominance.

apical dominance.

If a stem is severed from its root system: branches at the cut end will become positively gravitropic in response to the loss of an auxin sink in the root. Their apical meristems will take on root meristem identity once they contact the soil, due to ethylene accumulation. axillary buds near the cut end will take on root meristem identity due to the disruption of strigolactone transport, and, because root meristems are not repressed by apical dominance, they will begin to grow. the shoot will die because stems cannot produce new root meristems. auxin traveling down through the stem in the phloem will accumulate at the cut end and trigger the initiation of root meristem.

auxin traveling down through the stem in the phloem will accumulate at the cut end and trigger the initiation of root meristem.

Which of the following did NOT represent a challenge that plants faced in colonizing land from the ocean? (Select all that apply.) mechanical support hydration avoidance of herbivores dispersal of sperm and offspring protection from ultraviolet radiation

avoidance of herbivores

Which group of plants contains the tallest and oldest trees on Earth? conifers cycads angiosperms gnetophytes ginkgos

conifers

Plants can have _____ defenses, which are always active, or _____ defenses, which are produced only when a plant is threatened. mutualistic; symbiotic inducible; constitutive chemical; mechanical constitutive; inducible

constitutive; inducible

Photorespiration _____ O2 and _____ CO2.co releases; releases releases; consumes consumes; consumes consumes; releases

consumes; releases

Which of the following plants were first domesticated in North America? chocolate None of the answer options is correct. corn grapes cabbage

corn

The first line of plant defense against pathogen infection is/are the: plasmodesmata. cuticle. pathogens. stomata. cell walls.

cuticle.

The waxy substance on leaf surfaces is the: epidermis. stomata. leaf hair. mesophyll. cuticle.

cuticle.

Double fertilization in angiosperms results in a: diploid embryo and a triploid endosperm. diploid embryo and a diploid endosperm. haploid embryo and a haploid endosperm. diploid embryo and a haploid endosperm. triploid embryo and a diploid endosperm.

diploid embryo and a triploid endosperm.

A plant's siRNA response is triggered by the presence of: double-stranded RNA. single-stranded DNA. single-stranded RNA. double-stranded DNA.

double-stranded RNA.

In response to drying soils: elongation in roots is suppressed, leading to thick and tougher roots better able to pull water from the soil. cell division in roots accelerates, allowing roots to extend deeper into potentially wetter soil layers. elongation in roots is promoted, allowing roots to extend deeper into potentially wetter soil layers. older root xylem walls thicken to resist the higher tensions needed to pull water from the soil.

elongation in roots is promoted, allowing roots to extend deeper into potentially wetter soil layers.

Most conifers are _____, meaning that they retain their leaves throughout the year. epiphytic deciduous evergreen ephemeral herbaceous

evergreen

Which of the vascular plants have swimming sperm and rely on liquid water in the environment to achieve fertilization? ferns, horsetails, and lycophytes ferns, horsetails, and gymnosperms gymnosperms and lycophytes lycophytes and gymnosperms

ferns, horsetails, and lycophytes

The conservation of genetic diversity in both crops and their wild relatives is important because: (Select all that apply.) genetically uniform agricultural populations act as strong selecting agents for the evolution of novel diseases and pests. domestication and selection for yield tends to reduce the genetic variation within crops over time. due to artificial selection, modern crop cultivars have lost the ability to reproduce themselves. genetically uniform agricultural populations may be highly susceptible to diseases and pests.

genetically uniform agricultural populations act as strong selecting agents for the evolution of novel diseases and pests. domestication and selection for yield tends to reduce the genetic variation within crops over time. genetically uniform agricultural populations may be highly susceptible to diseases and pests.

Which group of gymnosperms has only a single, living representative species? gnetophytes lycopodium ginkgos conifers cycads

ginkgos

Land plants are descended from: mosses. green algae. brown algae. cyanobacteria.

green algae.

In mosses, the green, leafy portion represents which generation in the alternation of generations? haploid sporophyte haploid gametophyte diploid gametophyte haploid spore diploid sporophyte

haploid gametophyte

Unlike how animals circulate their blood, trees transport water: in an open system driven by evaporation. by direct expense of metabolic energy. without specialized tissues for long-distance transport. in a closed, recirculating system.

in an open system driven by evaporation.

In what type of environment would you expect to find a plant that spends most of its resources on defenses, rather than growth? (Select all that apply.) in the nutrient-poor soil of a tundra in the sandy soil of a rainforest in the clay soil of a rainforest on well-fertilized farmland

in the nutrient-poor soil of a tundra in the sandy soil of a rainforest

Sexual reproduction in plants results in: (Select all that apply.) increased genetic diversity. offspring that are genetically different from the parent(s). offspring that are genetically different from each other. offspring that are genetically identical to the parent.

increased genetic diversity. offspring that are genetically different from the parent(s). offspring that are genetically different from each other.

The primary site of photosynthesis in MOST plants is the: leaves. stems. buds. shoots. roots.

leaves.

A researcher examines a piece of oak tree bark under a microscope. He notices many small holes or spaces within his bark sample. What are these areas? suberins pericycles stomata lenticels

lenticels

In bryophytes, the: sporophyte produces spores by mitosis. haploid gametophyte produces diploid spores by fertilization. diploid gametophyte produces haploid spores by meiosis. male gametes are dispersed by wind. male gametes require water to reach the female gametes.

male gametes require water to reach the female gametes.

Plant growth results from actively dividing cells called: meristem cells. vascular cells. bundle sheath cells. primordial cells. nodes.

meristem cells

Grass plants have evolved a growth form that protects _____ by keeping them close to ground level. flowers meristems leaves stems

meristems

Angiosperms that have only one embryonic seed leaf are called: eudicots. monocots. gnetophytes. ginkgos. bryophytes.

monocots.

Which of the following plants are bryophytes? ferns horsetails mosses gymnosperms angiosperms

mosses

Flowers provide rewards to their pollinators such as: shelter. nectar. pleasant scents. colorful petals.

nectar.

Monocots demonstrate which of the following characteristics? (Select all that apply.) a vascular cambium that produces secondary xylem new roots that consistently form at nodes along the stems nodes giving rise to single leaves vascular bundles organized in a ring

new roots that consistently form at nodes along the stems nodes giving rise to single leaves

Within each "unit" composing a shoot of a vascular plant, you would observe leaves attached at the _____, and a large stretch of stem without leaves at the _____. node; internode node; shoot apical meristem shoot apical meristem; node internode; node

node; internode

A fruit is a mature: stem. stigma. ovule. pollen grain. ovary.

ovary.

Roots branch by forming new meristems in the: axillary position relative to root hairs, analogous to shoot branching from buds axillary to leaves. pericycle, thereby maintaining continuous contact with the vascular system of the parent root. epidermis, which allows roots to initiate in response to local soil conditions. pith, a source of stored carbohydrate for growth of the new root.

pericycle, thereby maintaining continuous contact with the vascular system of the parent root.

Fossils show that leaves MOST likely evolved from: endosymbiotic cyanobacterium. photosynthetic stems. vascular tissue. lateral meristems. algal cells.

photosynthetic stems.

The movement of auxin from the apical to basal sides of immature leaf cells and toward the xylem and phloem of the stem is an example of _____ transport. trophic bidirectional paraxial polar

polar

The transport of the pollen to the ovule is called: ovulation. germination. reproduction. fertilization. pollination.

pollination.

Which of the following are chemical compounds (or proteins) produced by plants that interfere with an herbivore's ability to break down proteins? (Select all that apply.) protease inhibitors terpenes alkaloids phenols

protease inhibitors phenols

Plants are able to defend themselves against viruses that have invaded their cells by: recognizing viral RNA and interrupting its replication. producing sticky proteins on the cell surface that capture the viruses. increasing the number of plasmodesmata per cell. causing the virus to detach from the cell membrane before it injects its RNA. producing antibodies.

recognizing viral RNA and interrupting its replication.

The last common ancestor of gymnosperms and angiosperms possessed which of the following characteristics? (Select all that apply.) seeds double fertilization pollen flowers vascular tissues

seeds pollen vascular tissues

Which of the following are points of entry through which viral and bacterial pathogens can infect plant tissues? (Select all that apply.) sites of herbivore damage open stomata leaf hairs the cuticle

sites of herbivore damage open stomata

Vascular plants hydrate photosynthetic cells using _____, whereas bryophytes do so using _____. xylem; surface water soil water; surface water surface water; soil water xylem; phloem

soil water; surface water

Xylem sap and soil water differ in _____ because of _____. solute composition; selective uptake by mycorrhizae solute composition; selective uptake by the epidermis pH; H+ exclusion by the endodermis solute composition; selective uptake by the endodermis

solute composition; selective uptake by the endodermis

In plants, _____ are defined as haploid (1n) cells that develop into gametophytes. Gametophytes, in turn, produce either haploid (1n) male or female _____ that can fuse to form diploid (2n) _____. gametes; spores; zygotes gametes; zygotes; spores spores; zygotes; gametes spores; gametes; zygotes zygotes; spores; gametes

spores; gametes; zygotes

Which of the following is a component of the sporeor zygotewall (in mosses, ferns, gymnosperms, and angiosperms) and helps prevent the desiccation of these structures? peptidoglycan sporopollenin sporangia chitin sporangium

sporopollenin

The orientation of plant growth can respond to gravity because: starch grains within meristem cells are denser than the cytoplasm and move in response to gravity. meristems experience the pull of gravity directly. The cell's cytoskeleton bends in response to gravity. auxin flows "downhill" within the plant due to force of gravity acting on each auxin molecule.

starch grains within meristem cells are denser than the cytoplasm and move in response to gravity.

The timing of _____ is a feature that distinguishes CAM and C4 photosynthesis. rubisco activity and the Calvin cycle mitochondrial respiration carbohydrate production stomatal opening

stomatal opening

Grass plants elevate their leaves to compete for light without exposing their shoot apical meristems to grazing animals by: (Select all that apply.) using axillary meristems to produce leaves. suppressing internode elongation between leaves. never elevating the shoot apical meristem. growing their leaves from persistent meristematic zones at the leaf base.

suppressing internode elongation between leaves. growing their leaves from persistent meristematic zones at the leaf base.

Unlike xylem, phloem is made up of cells: whose contents move due to pressure-driven flow. that are still metabolically active. that transport solutes. that run the length of the plant.

that are still metabolically active.

The type of defense in which plants produce chemicals that cause the uninfected cells around a site of infection to die, leading to isolation of the infected region, is called: the wilting response. the hypersensitive response. avirulent resistance. systemic acquired resistance. biotrophic defense.

the hypersensitive response.

In vascular plants, water transport works only if: xylem and phloem are in close proximity. the xylem has access to a constant source of ATP. roots are able to generate turgor pressure. the water column is continuous between leaves and soil.

the water column is continuous between leaves and soil.

Recall that plants produce physical barriers (e.g., a cuticle or bark) to prevent pathogen infections. How can a pathogen enter, and ultimately infect, its host plant? (Select all that apply.) by being drawn up from the soil with water through wounds made by farming equipment through the stomata through wounds made by insects

through wounds made by farming equipment through the stomata through wounds made by insects

The wood of gymnosperms is composed of _____, and the wood of angiosperms (e.g., a cherry tree) can consist of _____. fibers and tracheids; vessel elements tracheids and vessel elements; fibers tracheids; fibers and vessel elements vessel elements and fibers; tracheids

tracheids; fibers and vessel elements

Limits to the capacity of the _____ to store _____ can limit the rate of carbohydrate production in CAM leaves. vacuole; organic acids vacuole; phosphoenol pyruvate leaf; CO2 leaf; HCO3-

vacuole; organic acids

The movement of RNA through plasmodesmata is an important mode of cell to cell signaling, but also furnishes a pathway for the spread of infection by: bacteria. viruses. fungi. oomycetes.

viruses.