BIOLOGY EXAM 3

Blocking the proton pumps in a root would result in a more negative membrane potential and an increase in K+ uptake. TRUE OR FALSE

FALSE

Using biotechnology, plant breeders attempt to find and incorporate specific resistance genes into plants that lack them. Once a plant has been given a resistance gene, it will have indefinite protection from the associated pathogen. TRUE OR FALSE

FALSE

A decrease in the availability of ATP in a root cell could decrease the water potential of the cell. TRUE OR FALSE

False

Cavitation would have no effect on translocation. TRUE OR FALSE

False

Effects of light on chlorophyll synthesis While researching the effects of light on chlorophyll synthesis in sorghum, you find that brief pulses of red light stimulates the synthesis of chlorophyll a and b. This would suggest that chlorophyll synthesis is directed by the Pr form of phytochrome. TRUE OR FALSE

False

Plants that sequester heavy metals utilize pressure-flow where they move toxins from the source (soil) to a sink (such as the leaves). TRUE OR FALSE

False

Saline soils have a higher water potential than plant roots. TRUE OR FALSE

False

When CO2 is high Which of the following actions occurs in many plants when CO2 concentrations are high?

Guard cells lose turgor, and the stomata close.

Chemical substances produced in small quantities _______________ are chemical substances produced in small quantities in one part of an organism and then transported to another part of the organism, where they bring about physiological responses.

Hormones

Which genetic modifications would modify flowering time? One way to improve crop productivity is to modify flowering time. This can allow for multiple growing seasons in one year, and can also increase grain production because a smaller plant has lower resource needs. You are approached by an agricultural company that wants to create an early-flowering transgenic plant. Using your knowledge of Arabidopsis genetics, which genetic modifications would you suggest?

Inhibition of the embryonic flower ( EMF) gene or overexpression of the LEAFY (LFY) gene would work.

How does jasmonic acid contribute to the activation of the wound response in tomato plants?

It signals gene expression, leading to the production of a proteinase inhibitor.

A scientist is investigating a hormone response in rose bush stems by removing the apical meristems of the main stems. What is the most likely result of this experiment and what hormone is responsible?

Lateral buds will develop under the influence of cytokinin.

What is not true about meristems? Which of the following is not true about meristems?

Meristematic cells are found only in eudicots and not in monocots.

Inside nitrogen-fixing nodules, one N2 molecule is converted into two

NH3

A soil sample A soil sample with a OH- concentration of 10-9 M may also have high levels of aluminum. TRUE OR FALSE

TRUE

Secondary growth Which statement about secondary growth in plants is not correct?

The cork cambium produces secondary phloem while the vascular cambium produces secondary xylem.

Why might seeds fail to germinate? Your friend has never gardened before. When none of the seeds he planted germinate, he asks you to suggest why. Which is the best explanation of what occurred?

The seeds were planted too deeply and used up their reserves before reaching the surface and sunligh

The epicotyl: which statement is TRUE? Which of the following statements about the epicotyl is true?

The shoot apical meristem of a seedling is located just above it.

Darwin, Went, and others study of auxin Several scientists, including Charles and Francis Darwin, Frits Went and others, demonstrated that auxins caused stems to bend toward light in a series of elaborate experiments. Went was the researcher who finally determined that bending of the stem toward light was a result of which mechanism?

The transport of auxin to the shaded side of the plant stem stimulated stem elongation and a bending in the direction of the light.

Tree-of-Heaven In your garden, you have an Ailanthus altissima, also known as the Tree-of-Heaven. You try adding additional plants to the same garden bed, but notice poor seed germination and seedling growth around the tree. What is the most likely explanation for this?

The tree is releasing chemicals into the soil that are inhibiting germination and growth of other plants.

A false statement about plant secondary metabolites? Which of the following is a false statement about plant secondary metabolites?

They are too unpredictable to use in pharmaceutical research.

Aquaporins Which of the following statements does not apply to aquaporins?

They are unique to plant cells

Why is it beneficial that soil is negative? Why is it beneficial to plants that soil particles have negatively-charged surfaces?

They attract positively-charged ions and prevent them from being washed deep into the soil.Correct

Why do plants use the photoperiodic pathway? Why do many plants use the photoperiodic pathway to regulate the timing of flower formation?

This allows plants to link flowering to day length, which corresponds to the season when conditions are optimal.

A parasitic plant without chlorophyll is likely to lack leaves. TRUE OR FALSE

True

If the soil around a plant is treated with a fungicide, the plant may experience a decline in DNA synthesis. TRUE OR FAlSE

True

Will a self-pollination allele will be selected for in the Arctic? Thanks to a novel recessive mutation, a certain plant species has begun to invade colder Arctic regions outside of its normal range. However, this cold-tolerant mutation has not yet become fixed in the population. A second mutation arises that promotes self-pollination. Do you predict that the self-pollination allele will be selected for in the Arctic regions? Why or why not?

Yes. The self-pollinated plant is more likely to maintain the cold-tolerant mutation, and plants in the Arctic are unlikely to be visited by pollinators.

Situations regarding phloem Which of these situations regarding phloem sources and sinks is not correct?

Young leaves are sinks.

What part of seed has starch enzymes? Which part of the seed produces hydrolytic enzymes that break down the starchy endosperm during seed germination?

aleurone layer

What compartments hold starch? Germination requires the use of metabolic reserves in the seed. Which of these compartments contains starch used to fuel early seedling growth?

amyloplasts

Primary growth originates where? Primary growth in plants originates in

apical meristems.

Plant hormone in phototropic response Which naturally-occurring plant hormone has a major role in the phototropic response of plants?

auxin

When seeds are removed from strawberries, fruit growth is stopped. This suggests the seeds contain which of the following hormones?

auxin

The acid growth hypothesis links

auxin to cell wall expansion.

Two season plants? What are plants that flower only once before they die, normally after two seasons of growth, called?

biennials

Required by plants in the smallest quantity? Which of the following is required by plants in the smallest quantity?

boron

Structures with aerenchyma Which of these structures is not likely to contain significant amounts of aerenchyma tissue?

coconut tree roots

Recipe for rhubarb pie You come across a recipe for rhubarb pie. Never having heard of rhubarb, you do a little research. You find out that the part of a rhubarb plant that people eat is the petiole of a large leaf. You purchase some rhubarb for your pie and notice that it contains many long stringy fibers. Based on your knowledge of plant tissues, you know that the stringy fibers are

collenchyma tissue.

Primary growth at the apical meristems can produce cells that differentiate into each of these cell types, except which?

cork cambium

Damage to the ground meristem of a plant would result in

decreased sugar production.

Pathogen-specific response The steps in the pathogen-specific response do not include

development of antibodies.

The formation of the endosperm and the embry... What process results in the formation of the endosperm and the embryo in angiosperms?

double fertilization

Which is not a flower part? Which of the following is not a floral structure?

endosperm

Natural communities recycle nutrients, but cultivated communities often require an input of mineral nutrients due to losses through

erosion

Cloned gene for a plasma membrane transporter Inserting a cloned gene for a plasma membrane transporter into crop plants could lead to

extra uptake of minerals that would fortify the crop for human consumption.

Linen is woven from strands of sclerenchyma _______ that occur in the phloem of flax (Linum spp.).

fiber

Commitment to making a flower is called? At a certain point in the flowering process, shoots become committed to making a flower. This is called

floral determination.

wer gene in roots If the wer gene were expressed in every root epidermal cell, the plant would

greatly reduce its water and nutrient uptake.

Which plants are a frugal choice? Browsing through a seed catalog, you are tempted to order several beautiful floral varieties, but worry that you will spend too much on your garden every year. Which plants should you buy?

herbaceous perennials, which will come back year after year

Transpiration works because The process of moving water through a plant by transpiration works because water molecules stick to each other with

hydrogen bonds.

Activation of proteinase inhibitor genes The activation of proteinase inhibitor genes occurs

in the nucleus of the affected cells.

Mechanisms for water loss Mechanisms that evolved in plants to regulate the rate of water loss do not include

increasing the number of water vacuoles in the cells.

Secondary phloem

is part of the inner bark.

What discourages self-pollination? Which of these characteristics would most likely discourage self-pollination in a flower with both stamens and pistils?

long pistils and short stamens

Plant cells that give rise to two cells, one of which is free to differentiate into various kinds of cells that contribute to the plant body, are called

meristematic cells.

Symbiotic relationships Although symbiotic relationships between nitrogen-fixing bacteria and plants are rare, many plants have symbiotic relationships with

mycorrhizal fungi in the soil.

Which is not a modified stem? Which of the following is not a modified stem?

spine

Water that evaporates from leaves Most of the water that evaporates from leaves passes out through the

stomata

Humus often enhances the water and nutrient-retaining properties of topsoil. Which of the following might increase the humus content of a soil? Check all that apply.

-ground limestone -phosphate fertilizer

Dermal tissue in plants

-is several cell layers thick -houses guard cells that defend against pathogen invasion.

Corolla, calyx, and...? Your botany instructor likes to tell nerdy jokes, like this: "I wanted to buy a pink Toyota Corolla, but the dealer only had a green Calyx available." Impress your instructor with a clever response to this joke.

"Me too! But I could only afford the yellow Androecium."

Which of the following statements about abscisic acid are true? Check all that apply.

-It is produced chiefly in mature green leaves and in fruits. -It promotes leaf senescence. -It plays an important role in controlling the opening and closing of stomata. -It plays a role in seed dormancy.

Why is hydroponic solution aerated When plants are grown in hydroponic culture, their roots are suspended in an aerated solution. Why is the solution aerated? Check all that apply.

-Oxygen is necessary for the root cells to produce ATP. -Without oxygen, membrane transport in the roots would be impaired. -Without oxygen, the xylem would stop flowing.

Ants and acacia trees Which of the following statements about the relationship between ants and acacia trees is/are accurate? Check all that apply.

-The ants protect the acacias from other insects. -The ants protect the acacias from epiphytic plants and vines. -The ants live in the hollow thorns of the acacias. -The ants are provided with sugar or other nutrition by some species of acacia.

Which of the following are true statements about gibberellins? Which of the following are true statements about gibberellins? Check all that apply.

-They can restore normal growth and development in certain dwarf mutants. -They are produced in the apical regions of shoots and roots. -They promote internode elongation. -They hasten seed germination.

Pure water without applied pressure has a water potential that is equal to

0.0 MPa.

Where will the birdhouse be later? A birdhouse is nailed into a tree 6 feet up from the ground. If the tree grows about 2 feet taller each year, where will the birdhouse be 25 years later?

6 feet

Long-day plants and phytochrome Interrupting the night with a flash of light can trigger flowering in a long-day plant. Why doesn't introducing a short period of darkness during the day cause a short-day plant to flower?

A brief dark period is not sufficient to trigger flowering.

Root hairs Which statement concerning root hairs is not correct?

A root hair is isolated from its epidermal cell with a cross wall.

Flowering plants: which statement is TRUE? Which of the following statements about flowering plants is TRUE?

A short-day plant requires nights longer than a certain critical period to trigger flowering.

Why is popcorn triploid? You go to the movies with a friend, and he refuses to share your popcorn. He says that he heard that movie theatre popcorn is triploid. What is the most likely explanation for this?

All popcorn is triploid, because the starchy part of the kernel is triploid endosperm tissue.

When coleoptiles are illuminated What happens when coleoptiles are illuminated with directional light from the side instead of from directly overhead?

Auxin is transported away from the lighted side.

What is the name of elongated structure connecting embryo to nutrients? What is the name of the elongated structure that links the embryo to the nutrient tissue of the seed?

suspensor

Plant tissue culture: which statement is FALSE? Which of the following statements about plant tissue culture is false?

Callus tissue can only form roots, not shoots.

Root hairs grow actively where? Root hairs grow actively in which area of the developing roots?

zone of maturation

Root hairs vs. small roots How could you distinguish between a root hair versus a very small root?

Root hairs are extensions of single cells, while roots are multicellular.

seed dormancy Which of the following about seed dormancy is not true?

Seed dormancy is common in tropical climates.

A plant has a mutation in the gene that codes for systemin. What is the likely consequence of this mutation?

Systemin receptors will not be activated and proteinase inhibitor will not be transcribed.

An experiment where root hairs are treated with an antibiotic You propose an experiment where root hairs of a particular plant species are continuously treated with an antibiotic while nutrient levels in the plant tissue are monitored. Based on your knowledge of root hairs, you hypothesize the plant will experience a deficiency in what nutrient?

nitrogen

Carnivorous plants evolved because which of the following nutrients is often extremely limited in their habitats?

nitrogen

The uneven distribution of an impermeable solute on either side of a membrane will result in

osmosis

Vascular bundles of most dicot stems In the vascular bundles of most dicot stems, primary phloem differentiates toward the ________ of the stem, while primary xylem differentiates toward the ________ of the stem.

outside; middle

Which plant cells are the most common and the least specialized?

parenchyma

What morphological changes allow insect pollination? A genus of primarily wind-pollinated plants includes one unusual species that has evolved to be pollinated by insects. Several morphological changes have accompanied this adaptation. The ______________ are more colorful, there is a nectary at the base of the ______________, the ________________ are shorter and produce sticky pollen, and the __________________ are stickier for enhanced pollen capture.

petals; sepals; stamens; carpels

Slender stalk connecting leaf blade to stem The slender stalk that connects the flattened leaf blade to the stem in most dicots is the

petiole

Identify tissue in a plant sample You have been given a plant sample and asked to identify a specific tissue. Upon investigation, you find the cells are all long in length and some of them have small pores. They all contain fluid. You test the fluid using various biochemical tests and discover the fluid contains an abundance of disaccharides. What type of tissue are you looking at?

phloem

Charles Darwin and his son experimented with which plant growth response?

phototropism

One effect of auxin, which triggers the elongation of cells, is to affect cell walls by increasing their

plasticity

What is transferred between flowers? Flowering plants use animals or wind to transfer ________ between flowers.

pollen

What part CAN not reproduce asexually? Which tissue can not divide to give rise to identical progeny in a plant that reproduces asexually?

pollen grain

What do microspores develop into? Microspore mother cells produce microspores. What do microspores then develop into?

pollen grains

Rapid turgor pressure changes in specialized multicellular swellings called ____________ are associated with leaves that move in response to touch or light.

pulvini

Secondary metabolite used as an antimalarial drug? Which of the following plant secondary metabolites is used as an antimalarial drug?

quinine

What is LEAST likely to attract pollinators? Which of the following factors is LEAST likely to attract pollinators to a flower?

taste of the ovules

In several studies of plant responses to elevated CO2 concentrations in the atmosphere, scientists often found that the stimulation of growth gradually diminished because

the soil did not contain sufficient nitrogen and other nutrients to support the enhanced growth.

Nonnative plant invaders, such as the alfalfa plant bug, are extremely invasive and hard to control because

they arrive in new locations where natural predators are not present.

A plant will usually wilt when which component of water potential reaches 0 MPa?

turgor pressure

A stem that cannot increase in diameter lacks what? A stem that cannot increase in diameter is lacking what type of tissue?

vascular cambium

Which cell type conducts water most rapidly through a plant? Which of the following cell types conducts water most rapidly through a plant?

vessel members

You are given a root tip in lab Your lab instructor hands you a root slide and asks you to show her a cell with condensed chromosomes arranged in a straight line. In which section of the root would you begin your search?

zone of cell division