Answer

You are studying a plant from the arid southwestern United States. Which of the following adaptations is least likely to have evolved in response to water shortages?

Development of large leaf surfaces to absorb water

Which part of a plant absorbs most of the water and minerals taken up from the soil?

root hairs

An evolutionary adaption that increases exposure of a plant to light in a dense forest is....

apical dominance

A person working with plants may remove apical dominance by...

pruning

Land plants are not composed of what tissue?

mesodermal tissues.

Vascular plant tissue includes all of the following cell types except

cambium cells

What functional plant cells lack a nucleus?

xylem and sieve-tube cells

Long, thin tapered cells with lignified cell walls that function in support and permit water to flow through pits

sclerenchyma

Living cells that lack nuclei and ribosomes: they transport sugars and other organic nutrients

sieve cells

The least specialized plant cells, which serve general metabolic, synthetic, and storage functions

Parenchyma

Cells with unevenly thickened primary walls hat support still-elongating parts of the plant

Collenchyma

Mature cells without protoplasts with thick, lignified secondary walls that may not function in transport

Sclerenchyma

Which of the following is not a characteristic of parenchyma cells?

Have secondary thickenings

Which of the following tissues is incorrectly matched with its characteristics?

collenchyma- uniformly thick-walled supportive tissues

The fiber cells of plants are a type of

sclerenchyma

The vascular bundle in the shape of a single central cylinder root is called

stele

One important difference between the anatomy of roots and the anatomy of leaves is that..

a waxy cuticle covers leaves but is absent in roots

the photosynthetic cells in the interior of a leaf are what kind of cells:

parenchyma

A student examining leaf cross sections under a microscope finds many loosely packed cells with relatively thin cell walls. The cells have numerous chloroplasts. What types of cells are these?

Parenchyma

­Which of the following is true about secondary growth in plants?

Secondary growth is produced by both the vascular cambium and the cork cambium

A friend has discovered a new plant and brings it to you to classify. h eplant has the following characteristics a taproot system with growth rings evident in cross section and a layer of bark around the outside. It is?

Woody eudicot

Shoot elongation in a growing bud is due primarily to..

cell elongation localized in each internod

Axillary buds develop from

meristematic cells left by the apical meristem

Gas exchange, necessary for photosynthesis, can occur most easily in which leaf tissue?

spongy mesophyll

What is the correct sequence from the growing tips of the root upward?

root cap, apical meristem, zone of cell division, zone of elongation, and zone of maturation

Which of the following is incorrectly paired with its structure and function?

Pericycle- waterproof ring of cells surrounding the stele in roots

Which of the following root tissues gives rise to lateral roots?

Pericycle

Pores on the leaf surface that function in gas exchange are called:

stomata

Which of the following is a true statement about growth in plants

some plants secondary growth

Which of the following cell types are correctly matched with their functions except...

companion cell-formation of secondary xylem and phloem

What tissue makes up most of the wood of a tree?

secondary xylem

The vasclar system of a three-year-old eudicot stem consists of

3 rings of the xylem and 1 rings of the phloem

Which of the following is true of bark?

It is composed of phloem plus periderm.

Suppose Geroge completely removed the bark from around the base of a cherry tree but was stopped by his father before cutting the tree down. Plant lived for several weeks but then died. What tissue was left?

xylem

Additional vascular tissue produced as secondary growth in a root originates from which cells?

vascular cambium

Before differentiation can begin during the process of plant cell and tissue culture, parenchyma cells from the source tissue must

undergo differentiation

In leaves, chloroplasts are found in

palisade mesophyll

------- provides cells for secondary growth.

Vascular cambium

Secondary grrowth never occurs in

leaves

How is he supply of vascular cambium maintained?

Through the division of cells

Which structure is incorrectly paired with its tissue?

companion cell-ground tissue

Wood consists of

secondary xylem.

Which of the following is not part of an older tree's bark?

secondary xylem

Which of the following arises from meristematic activity

Secondary xyelm, leaves, trichomes, and tubers (all of the above)

------ is to xylem as ---- is to phloem.

vessel element; sieve-tube member.

The driving force that pushes the root tip through the soil is due primarily to:

elongation of cells behind the root apical meristem.

------ provides cells for primary growth

apical meristems

Answer

Which of the following would least likely to affect osmosis in plants?

receptor proteins in the membrane

Active transport involves all of the following except the

slow movement through the lipid bilayer of a membrane

Like many plants process, transport of various material in plans at the cellular level requires all of the following except:

xylem membranes

Which of the following is an example of osmosis?

flow of water out of a cell, flow of water between cells

The amount and direction of movement of water in plants can always be predicted by measuring which of the following?

water potential

Which of the following is true concerning the water potential of a plant cell?

It is equal to zero when the cell is in pure water and is turgid.

Your laboratory partner has an open beaker of pure water. By definition, the water potential of this water is?

zero

Which of the following has an effect on water potential in plants?

air pressure, water-attracting matrices and dissolved solutes

If Wp =.3 MPa and Ws = -.45 then this equals

-.15 MPa

The value for water potential in a root was found to be -.15 MPa. If you take the tissue and place it in a solution of sucrose with a -.23, water will flow where?

from the tissue into the sucrose

COmpared to a cell with a few aquarporins in its membrane, a cell containing many aquaporins will...

have a faster rate of osmosis

Some botanists agree tha the entire plant should be considered a single unit rather than a composite of may individual cells. Which of the following cellular structures cannot be used to support this view?

tonoplast

Which of the following statements is false about bulk flow?

It depends on the force of gravity on a column of water.

Which of the following statements about xylem is incorrect?

It transports mainly sugars and amino acids

Which of the following would likely not contribute to the surface area available for water absorption from the soil by a plant root system?

endodermis (they are water resistant and waxy)

Root hairs are most important to a plant because they ...

increase the surface area for absorption

What is the role of proton pumps in root hair cells?

acquire minerals form the soil

In plant roots, the casparian e strip is correctly described by which of the following?

It ensures that all water and dissolved substance must pass through a cell before entering the stele

All of the following describe an important component of the long-distance transport process in plants except

endodermis Casparian strip

Pine seedlings grow in sterile potting soil grow much slower than seedlings grown in soil from the are 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.

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 part of what structure?

the endodermis

The following factos may sometimes play a role int he movement of sap through the xylem. Which one depends on the direct expenditure of ATP by the plant?

concentration of ions in the symplast

What is the main cause of guttation in plants

root pressure

One is the most likely to see guttation in small plants when the..

root pressure exceeds transpiration pull

What is the main force by which most of the water within xylem vessels moves toward the top of a tree?

evaporation of water through the stoma

In which plant cell or tissue would the pressure component of water potential most often be negative?

stem xylem

Water potential is generally most negative in which of the following part of a plant?

mesophyll cells of the leaf

Which of the following has the lowest (most negative) water potential?

leaf air spaces

Which of the following is responsible for the cohesion of water molecules

hydrogen bonds between the oxygen atom of one water molecule and a hydrogen atom of another water molecule

Active transport would be least important in the normal functioning of which of the following plant tissue types?

stem xylem

Guard cells do which of the following?

help balance the photosynthesis-transpiration compromise

All of the following normally enter the plant through the roots except:

carbon dioxide

Photosynthesis begins to decline when leaves wilt because

stomata close, preventing CO2 entry into the leaf

The water lost during transpiration is an unfortunate side effect of the plant's exchange of gases. However, the plant derive some benefit from this water loss in the form of..

evaporative cooling and increased turgor

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

If the guard cells and surrounding cells in a plant are deficient in potassium ions, all of the following would occur except..

leaf temperatures would decrease

The opening of stomata is thought to involve...

an increase in the osmotic concentration of the guard cells

Which of the following experimental procedures would most likely reduce transpiration while allowing the normal growth of a plant?

Increasing the level of carbon dioxide around the plant.

All of the following are adaptation that help reduce water loss from a plant except..

transpiration

Phloem transport of sucrose can be describe as going from "source to sink". Which of the following would not normally function as a sink?

mature leaf

Which of the following is a correct statement about sugar movement in phloem?

Movement can occur both upward and down in the plant.

Phloem transport is described as being from source to sink. Which of the following would most accurately complete this statement about transport? Phloem transport --- from the --- source to the--- sink.

Phloem transports sugars from the leaf source to the apical meristem sink.

Explain the mass flow of materials in the phloem?

leaf cells produce sugar by photosynthesis; Sugar is transported from cell to cell in the leaf; Solutes are actively transported into sieve tubes; water diffuses into the sieve tubes; sugars moves down the stem

Water flows into the source end of a sieve tube because

sucrose has been actively transported into the sieve tube, making it hypertonic

Which one of the following statements about transport of nutrients in phloem is false?

Companion cells control the rate and direction of movement of phloem sap.

According to the pressure flow hypothesis of phloem transport,

solute move from a high concentration in the "source" to a lower concentration in the "sink"

Which of these involves a symbiotic relationship?

mycorrhizae

------ increase the surface area of roots.

Root hairs and mycorrhizae

In roots the ------- forces water and solutes through the plasma membranes of the ----- cells before entering the -------.

Casparian strip; endodermis; xylem

Sugars move from leaves into the ------ of ----- by ------.

Sugars move from leaves into the sieve-tube members of the phloem by active transport.

The water pressure that pulse water and sugar from sugar source to sugar sink is referred to as ----.

bulk flow

Transpiration in plants requires all of the following except

active transport through xylem cells.

Which of the following is an advantage of tracheids over vessels for long-distance transport to great heights?

Adhesive forces are proportionally greater in narrower cylinders than in wider cylinders and Cohesive forces are greater in narrow tubes than in wide tubes of the same height.

Guard cells are the only cells in the epidermis that contain chloroplasts and can undergo photosynthesis. This is important because...

ATP is required to power proton pumps in the guard cell membranes.

Answer

Which of the following describes the fate of most of the water taken up by a plant?

It is lost during transpiration

Most of the dry weight of a plant is the result of uptake of:

CO2 through stomata in leaves

Organic molecules make up what percentage of the dry weight of a plant?

96%

In hydroponic culture, what is the purpose of bubbling air into the solute?

to provide oxygen to root cells

Which two elements make up more than 90% of the dry weight of plants?

oxygen and carbon

The bulk of a plant's dry weight is derived from...

CO2

What are the three main elements of which plant growth and development depend?

oxygen, carbon, hydrogen

Which of the following elements is incorrectly paired with its function in a plant?

sulur- component of DNA; activates some enzymes

In the nutrition of a plant, which element is classified as a macronutrient?

calcium

Reddish-purple coloring of leaves, especially along the margins of young leaves, is a typical symptom of deficiency of which element?

P

Which of the following is not true of micronutrients in plants?

They are essential elements of small size and molecular weight.

A growing plant exhibits hclorosis of the leaves of the entire plant. The chlorosis is probably deficiency of which of the following macronutrients?

nitrogen

What is meant by the term chlorosis?

the yellowing of leaves due to decreased production

Iron deficiency is often indicated by chlorosis in newly formed leaves. This suggests that ...

iron is an immobile nutrient in plants

A soil well suited for the growth of most plant would have all the following properties except ...

a high pH

What soils is are the most fertile...

both humus and loam.

Why does overwatering a plant kill it?

The roots drowned (cannot get air)

What should be added to soil to prevent minerals from leaching away?

humus

The N-P-K percentages on a package of fertilizer refer to the...

percentages of three important mineral nutrients.

A young farmer purchases some land in a relatively arid area and is interested in earning a reason profit for many years. which of the following strategies would best allow such a goal to be achieved?

selecting crops adapted to arid areas

A farming commitment that embraces a variety of methods that are conservation-minded, environmentally safe, and profitable...

sustainable agriculture

An early use of indicator plants (plants that tolerate high levels of heavy metals in the soil) was to locate potential profitable areas to mine for those minerals. A current use for such plants is:

bioremediation to help clean up mine soils.

Nitrogen fixation is a process that..

converts nitrogen gas to ammonia.

Why is nitrogen fixation such an important process?

fixed nitrogen is most often the limiting factor in plant growth

In what way do nitrogen compounds differ from other minerals needed by plants?

Only nitrogen requires the action of bacteria to be made available to plants.

Most crop plants acquire their nitrogen mainly in the form of...

NO3-

The enzyme complex nitrogenase catalyzes the reaction that reduces atmospheric nitrogen to...

NH3

The most efficient way to increase essential amino acids in crop plants for human consmption...

breed for higher yield of deficient amino acids.

Among important crop plants, nitrogen-fixing root nodules are most commonly an attribute of ...

legumes

If a legume is infected with rhizobium, what is the probable effect on the plant?

It obtains nitrogen from nitrogen fixation.

You are weeding your garden when you accidentally expose some roots. You notice swellings (root nodules) on the roots. Most likely your plant ..

is benefiting from a mutualistic bacterium.

How do legume plant roots communicate Rhizobium bacteria..

Flavonoids trigger gene-regulating protein in bacterium.

A woodlot was sprayed with a fungicide. What would the most serious effect on such spraying

a decrease in tree growth due to death mycorrhizae

What is the mutualistic association between roots and fungi called?

mycorrhizae

Hyphae form a covering over roots. Altogether hyphae create a large surface area and do which of the following?

aid in absorbing minerals and ions

Which of the following is a primary difference between ectomycorrhizae and endomycorrhizae?

Ectomycorrhizae do not penetrate root cells, whereas endomycorrhizae grow into invaginations of the root cell membranes.

The earliest vascular plants on land had underground stems (rhizomes) but no roots. Water and mineral nutrients were most likely obtained by...

absorption by symbiotic fungi

Dwarf mistletoe grows on many pine trees in the Rockies. Although the mistletoe is green, it is probably not sufficiently active in photosynthesis to produce all the sugar it needs. The mistletoe also produces haustoria. So it is best classified as

a parasite.

What are epiphytes?

plants that grow on other plants but do not obtain nutrients from their hosts

Carnivorous plants have evolved mechanisms that trap and digest small animals. The products of this digestion are used to supplement the plant's supply of ...

minerals

What process is the source of the CO2 that root hairs release into the soil?

cellular respiration

Roots expend ATP to pump ________ ions from the root to the soil and by doing so displace mineral ions bound to soil particles.

H+

Acid precipitation..

decreases soil fertility

Denitriifying bacteria covert ------- to -------.

nitrates: nitrogen gas

Answer

The products of meiosis in plants are always which of the following?

spores

Which of the following is the correct sequence during alternation of generations in a flowering plant?

sporophyte-meiosis-gametophyte-gametes-fertilization-diploid zygote

Which of the following is true in plants?

Meiosis occurs in sporophytes to produce spore

All of the following are features of angiosperms except:

a small (reduced) sporophyte

Based on studies of plant evolution, which flower is not a modified leaf?

receptacle

All of the following floral parts are directly involved in pollination except the:

sepal

Floral parts would have the greatest impact on pollination?

Sepal or Petal

A mutation in which of the following floral parts would have the greatest potential impact on fertilization?

Stamen or carpel

Which of the following is the correct order of floral organs from the outside to the inside of a complete flower?

sepals, petals, stamens, carpels.

All of the following are primary functions of flowers except:

photosynthesis

Meiosis occurs within all of the following flower parts except the...

style

A perfect flower is fertile but may be either complete or incomplete. Which of the following correctly describes a perfect flower?

It has both stamen and carpels.

Carpellate flowers..

develop into fruits

which of the following types of plants is not able to self-pollinate?

dioecious.

In flowering plants, pollen is released from the ...

anther

In the life cycle of an agiosperm, which of the following stages is diploid..

microsporocyte

Where does meiosis occur in flowering plants?

megasporocyte and microsporocyte

Which of the following is a correct sequence of processes that takes place when a flowering plant reproduces?

meiosis, pollination, nuclear fusion, formation of embryo and endosperm

Which of these is incorrectly paired with its life-cycle generation?

anther- gametophyte

Which of the following is the correct sequence of events in a pollen sac?

microsporocyte-meiosis-microspores-mitosis-two haploid cells per pollen grain

Which of the following occurs in an angiosperm ovule?

A megaspore mother cell undergoes meiosis.

Where and by which process are sperm produced in plants?

Mitosis in male gametophytes

In which of the following pairs are the two terms equivalent?

embryo sac -- female gametophyte

Which of the following is the male gametophyte of a flowering plant?

pollen grain

In flowering plants, a mature male gametophyte contains...

two sperm nuclei and one tube cell nucleus.

Within the female gametophyte, three mitotic divisions of the megaspore produce..

three antipodal cells, two polar nuclei, one egg, and two synergids

The largest cell(s) of the typical angiosperm embryo sac is (are) the..

central cell

Which cells, after fertilization, give rise to the embryo plant?

egg cell

Which cells becomes the triploid endosperm?

polar nuclei

Which cells guide the pollen tube to the egg cell

tube cell

What is the relationship between pollination and fertilization in plants?

Pollination brings gametophytes together so that fertilization can occur

Recent research has shown that pollination requires that carpels recognize pollen gains as "self or non self". For self-incompatibility, the system requires

the rejection of self cells

As flowers develop, which transition does not occur?

The tube nucleus becomes a sperm nucleus.

The integuments of an ovule function to do what?

form a seed coat

A fruit includes

one or more seeds and has fleshy cells rich in sugars.

What is typically the result of double fertilization in angiosperms?

Both a diploid embryo and a triploid endosperm are formed.

Which of the following statements regarding the endosperm is false?

It develops from the fertilized egg.

In angiosperms, products of the terminal cell become the:

proembryo and the coteyledons

Which of the following statements is correct about the basal cell in a zygote?

It forms the suspensor that anchors the embryo.

What is the embryonic root called?

radicle

Which of the following "vegetables" is botanically a fruit?

green beans

Which of these structures is unique to the seed of a monocot?

coleoptile

Which of the following statements about fruits is false?

Fruits form from microsporangia and integuments

Fruits develop from

ovaries

The first step in germination of a seed is usually

imbibition of water

When seeds germinate the radicle emerges before the shoot. This allows the seedling to quickly...

obtain a dependable water supply

Which of the following is not true of the hypocotyl hook?

It is the first structure to emerge from a eudicot seed.

In plants, which of the following could be an advantage of sexual reproduction as opposed to asexual reproduction?

genetic variation

Which of the following is true about vegetative reproduction?

It produces clones.

Which of the following is a true statement about clonal reproduction in plants?

Making cuttings of ornamental plans is a form of fragmentation.

All of the following could be considered advantages of asexual reproduction in plants except..

adaptation of change.

Which of the following statements is true of protoplast fusion?

It can be used to form new plant varieties by combining genomes from two plants.

Which of the following statements is correct about protoplast fusion?

It can be used to form new plant species.

The most immediate potential benefits of introducing genetically modified crops include..

increasing crop yield.

Which of the following is not a scientific concern relating to creating genetically modified crops?

The monetary costs of growing genetically modified plants are significantly greater than traditional breeding techniques.

Currently available transgenic plants have been modified for all of the following traits except..

nitrogen fixation.

Flowers are made of modified..

leaves

Which of these is unique to the flowering plants?

double fertilization.

What is endosperm?

a food-storing tissue of the seed

________ is the first event in seed formation

pollination.

Which of the following statements is true about transgenic plants?

They contain genes from more than one species.

Answer

The step(s) between a plant's perception of a change in the environment and the plant's response to that change is (are) best called..

signal transduction

Which of the following statement is (are) true of plants?

Plants adjust their growth and development in response to environmental cues.

External stimuli would be received most quickly by a plant cell if the receptors for signal transduction were located in the...

cell membrane.

Secondary messengers are associated with which of the following?

transduction

In a signal transduction pathway, the transduction stage amplifies the original signal by...

Having each receptor molecule produce multiple secondary messengers and having each secondary messenger activate numerous specific enzymes.

What would happen if the secondary messenger cGMP was blocked in the de-etiolation pathway?

Ca 2+ channels could open, and specific protein kinase 2 could still be produced

If protein synthesis was blocked in eitiolated cells, what would be necessary for any de-etiolation to occur?

post-translational modification of existing proteins

Charles and Francis Darwin concluded from their experiments on photropism by grass seedlings that the part of the seedling that detects the direction of light is the...

tip of the coleoptile.

Pants growing in a partially dark environment will grow toward light in a response called phototropism. Choose the incorrect statement regarding phototropism:

Auxin causes a decrease in growth on the side of the stem exposed to light.

Which of these conclusions is supported by the research of both Went and Charles and Frances Darwin on shoot responses to light?

A chemical substance involved in shoot bending is produced in shoot tips.

We know from the experiments of the past that plants bend toward light because

cell expansion is greater on the dark side of the stem.

Plant hormones can be characterized by all of the following except that they:

function independently of other hormones

Why is it so difficult to study the actions of plant hormones?

All of the above make the study of plant hormones difficult.

Plant hormones can have different effects at different concentrations. This explains how ...

auxin can stimulate cell elongation in apical meristems, yet will inhibit the growth of axillary buds.

Which plant hormones might be used to enhance stem elongation and fruit growth?

auxins and gibberellins.

According to the acid growth hypothesis, auxin works by..

increasing wall plasticity and allowing the affected cell wall to elongate.

Which of the following hormones would be most useful in promoting the rooting of plant cuttings?

auxins

Which plant hormone(s) is (are) most closely associated with cell division?

cytokinin

One effect of gibberellins is to stimulate cereal seeds to produce ...

amylase

In attempting to make a seed break dormancy, one logically could treat it with..

gibberellins.

Both and red and blue light are involved in...

stem elongation.

Most plants close their stomata at night. What color of light would be most effective in promoting stomatal opening in the middle of the night?

blue

The biological clock controlling circadian rhythms must ultimately ...

affect gene transcription.

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.

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 temperatures.

A botanist exposed two groups of the same plant species to two photoperiods-one with 14 hours of light and 10 hours of dark and the other with 10 hours of light and 14 hours of dark. Under the first set of conditions, the plants flowered, why?

The plants flower in the spring.

In order to flower, a short-day plant needs a..

night that is longer than certain length.

A long-day plant is if..

the duration of continuous darkness is less than a critical length

Plants that have their flowering inhibited by being exposed to bright lights at night are:

short-day plants.

If you take a short-day plant and put it in a lab under conditions where it will flower (long nights and short days), but interrupt its day period with a few minutes of darkness, what will happen?

It will flower.

Florigen is a flowering signal, not yet chemically identified, found in:

leaves.

What do results of research on gravitropic responses of roots and stems show?

The effect of a plant hormone can depend on the tissue.

If you wanted to genetically engineer a plant to be more resistant to drought, increasing amounts of which of the following hormones might be a good first attempt?

abscisic acid

The initial response of the root cells of a tomato plant watered with seawater would be to..

begin to plasmolyze as water is lost.

Plants are affected by an array of pathogens. Which of the following is not a plant defense against disease?

All of the above are plant defenses against disease.

The breakdown of chlorophyll reveals the ________ pigments of a leaf...

carotenoid

The protective layer that forms between the abscission layer and the stem consists of ...

weak, colorless, thin-walled cells.

After leaf abscission, growth will resume from the..

petiole

What is the specific term that refers to seasonal changes in the relative lengths of night and day?

photoperiod

Day-neutral plants flower regardless of...

day length, night length, or photoperiod.

Which hormone is incorrectly paired with its function?

cytokinins—initiate programmed cell death

Buds and sprouts often form on tree stumps. Which of the following hormones would you expect to stimulate their formation?

cytokinins

How might a plant respond to severe heat stress?

By producing heat-shock proteins, which may protect the plants proteins from denaturing.