Deck 40: Plant Defense Responses

Question 1

Chemical toxins within plants

A)do not cost much energy to produce and be maintained.
B)are seldom maintained at steady-state levels.
C)are found mostly in the nuclei of the plant cells.
D)are only produced after a wound has occurreD.
E)are specific to certain families of plants.

Answer 1

E

Question 2

Which of the following statements about plant toxins against herbivores is false?

A)The toxin may be kept in a membrane-bound structure to keep it from harming the plant.
B)The toxin may not be toxic unless it is metabolized in the intestine of a herbivore.
C)The toxin may have also have a bad taste.
D)Even a little bit of the toxin will be deadly.
E)Some toxins can over stimulate particular physiological processes.

Answer 2

D

Question 3

Systemin can correctly be described as a(n)

A)peptide.
B)apoplast.
C)receptor.
D)leaf lipiD.
E)carbohydratE.

Answer 3

A

Question 4

Plants such as peppermint and sage contain oils.What is the function of these oils?

A)They help keep the plant from drying out.
B)They help repel insects.
C)They keep other plants from germinating nearby.
D)They prevent fungal infection.
E)They have hormone-like activity that helps wounds heal.

Question 5

Which of the following pairings is an example of coevolution of an organism's metabolism to resist a plant's evolved chemical defense?

A)the butterfly Helioconius sara and the glycosides produced by the passion flower vine
B)the tobacco hornworm and the tannins in tobacco plants
C)ants and acacia trees
D)humans and the glycosides in cassava
E)parasitoid wasps and the plants they eat

Question 6

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

A)they arrive in new locations where natural predators are not present.
B)they tap into the xylem of a plant while seeking carbohydrates.
C)they cause the plants' axillary buds to grow out.
D)their populations evolve faster than the plants they attack.
E)cause the plants' stomates to become unevenly distributed within the epidermis.

Question 7

Evidence that black walnut trees exhibit allelopathy includes

A)the lack of vegetation growing under black walnut trees.
B)the death of hornworms that try to eat black walnut leaves.
C)the symbiotic relationship the trees have with fungi.
D)the ants that protect the trees from herbivory.
E)the morphological changes that occur in response to pathogenic attacks.

Question 8

Which of the following chemicals do not help plants repel or poison invaders?

A)cyanogenic glycosides
B)alkaloids
C)tannins
D)carbohydrates
E)plant oils

Question 9

Which of the following methods do fungi use in order to penetrate the initial layer of a plant's defenses?

A)mechanical bridging
B)sharp mouthparts
C)entry through stomates
D)secretion of phospholipids to dissolve the cuticle

Question 10

How does systemin cause the activation of the wound response in tomato plants?

A)It binds directly to jasmonic acid.
B)It directly signals gene expression.
C)It induces the production of tannins.
D)It moves through the apoplast,and then travels through the phloem,where it induces a jasmonic acid signaling pathway in certain cells.
E)It triggers genes that are able to signal the plant that mechanical injury has occurred.

Question 11

Phytoestrogens are steroid-like chemicals that are derived from soy.One of their characteristics is that they are able to

A)paralyze nerve endings.
B)bind to the human estrogen receptor.
C)cause estrogen breakdown within human cells.
D)increase the rate of prostate cancer in men.
E)cure malaria.

Question 12

Which of the following statements about the relationship between ants and acacia trees is not accurate?

A)The ants protect the acacias from other insects.
B)The ants protect the acacias from epiphytic plants and vines.
C)The ants live in the hollow thorns of the acacias.
D)The ants are provided with sugar or other nutrition by some species of acacia.
E)The ants aid pollination of the acacias.

Question 13

Tannins are chemicals that help plants repel invaders by

A)over-stimulating the predator.
B)sedating the predator.
C)binding to proteins and thereby disrupting the predator's digestion.
D)injuring the external covering of the predator's body.
E)causing the predator to grow so rapidly that it dies.

Question 14

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

A)It moves through the phloem of the plant until it reaches the wound site.
B)It produces a polypeptide that binds with membrane lipids.
C)It binds to enzymes in the gut of the predator.
D)It increases the energy available for the plants to fight the predator.
E)It signals gene expression,leading to the production of a proteinase inhibitor.

Question 15

Parasitoid wasps are sometimes involved in a plant's defensive response.In what way are the wasps helpful to the plant?

A)The wasps respond to a chemical the plant gives off when wounded,and the wasps lay their eggs on the caterpillar that wounded the plant.
B)The wasps live in hollow thorns of the plants,and attack the plants' predators.
C)The wasps stimulate the production of alkaloids the plants use for defense.
D)The wasps enhance the plants' hypersensitive response.
E)The wasps trigger leaf abscission so that herbivores do not have anything to eat.

Question 16

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

A)morphine
B)taxol
C)genistein
D)quinine
E)manihotoxin

Question 17

____________ occurs when a chemical signal secreted by the roots of one plant blocks the germination of nearby seeds or inhibits the growth of a neighboring plant.

A)Nodulation
B)Etiolation
C)Reduction
D)Allelopathy
E)The systemic response

Question 18

Which of the following statements about plant secondary metabolites is false?

A)Some can be used to treat human diseases.
B)Some can be poisonous to humans.
C)The activity of certain medicines is due to secondary metabolites.
D)Some of them can cross the placenta during pregnancy.
E)They are too unpredictable to use in pharmaceutical research.

Question 19

Plants' first line of defense against attack by pathogens is

A)the thick walls of cells within the xylem tissue.
B)the dermal tissue system.
C)the plasma membrane of the cells.
D)various secondary metabolites,such as quinine.
E)the hypersensitive responsE.

Question 20

Which of the following steps is not one of the phases of a fungal invasion of a plant?

A)Windblown fungal spores land on plant leaves.
B)Hyphae grow through cell walls and press against the cell membrane.
C)Fungal DNA is replicated by the plant cells.
D)Hyphae differentiate into specialized structures called haustoria.
E)A fungal spore germinates and forms an adhesion pad that allows it to stick to a plant's leaf.

Question 21

Which of the following chemicals is a signal that induces systemic acquired resistance?

A)salicylic acid
B)brassinosteroids
C)systemin
D)avr
E)nitric acid

Question 22

The steps in the pathogen-specific response do not include

A)responding to the pathogen.
B)development of antibodies.
C)recognizing the pathogen.
D)triggering the hypersensitive response.
E)the pathogen releases distinctive proteins.

Question 23

What plant secondary metabolite was isolated from the Cinchona tree to fight malaria?

A)digitalis
B)penicillin
C)acacia
D)taxol
E)quinine

Question 24

The series of metabolic events that occurs within tomato plants in response to wounding is known as

A)a systemic response.
B)a waterfall effect.
C)the hypersensitive response.
D)a pathogen-specific response.
E)resistance to coevolution.

Question 25

What is the main difference between plant defense mechanisms that use secondary chemical metabolites versus plant defense mechanisms that use a systemic response?

A)The metabolites are not as lethal as the systemic response.
B)The metabolites are present at all times,and the systemic response must be induced.
C)The metabolites can only help in defense against insects,not against other plants.
D)The metabolites are toxic to the plants that produce them,the systemic response is safer.
E)The metabolites are a more reliable way to kill the invader.

Question 26

The activation of proteinase inhibitor genes occurs

A)in the cytoplasm of the affected cells.
B)on the plasma membrane of the affected cells.
C)in the nucleus of the affected cells.
D)before the systemin moves through the phloem of the plant.
E)in anticipation of a physical wound to the plant.

Question 27

Systemic acquired resistance is

A)a broad-ranging resistance that lasts for a period of days.
B)the same as the human immune response.
C)a response whereby antibodies recognize specific antigens.
D)a response that occurs when the hypersensitive response fails.
E)a method for plants to modify their DNA for protection.

Question 28

Cyanogenic glycosides are toxic because they break down into cyanide which

A)causes the plant's predator to vomit.
B)stops electron transport and cellular respiration.
C)turns on destructive genes within the pathogen.
D)turns on destructive genes within the plant.
E)causes the pathogen to dry out.

Question 29

Which pest can trigger knot-like tumors in plant roots?

A)aphids
B)mycorrhizae
C)Rhizobium bacteria
D)nematode worms
E)hornworms

Question 30

An invader is considered to be virulent if

A)it expresses avr genes.
B)it induces the hypersensitive response.
C)rapid cell death occurs around the site of the attack.
D)there is no R gene recognition of the invader.
E)systemic acquired resistance is triggered.

Question 31

For plant cells that have a systemin receptor,the receptor is located

A)on the plasma membrane.
B)on the nuclear membrane.
C)on the cuticle of the leaf.
D)inside the phloem sieve cells.
E)in the flowers.

Question 32

Why don't ants that protect the Acacia tree scare off bees trying to pollinate the tree's flowers?

A)They can't climb to the tops of the tree.
B)The bees are too big.
C)The bees fly in and out quickly.
D)The open flowers contain a chemical that is an ant deterrent.
E)Parasitoid wasps protect the bees from attack.

Question 33

Which common crop may contain traces of hormone-like substances that may affect human health?

A)corn
B)wheat
C)peanuts
D)soybean
E)wine grapes

Question 34

Which of the following statements does not characterize the hypersensitive response?

A)Rapid cell death occurs around the site of the attack.
B)A proteinase inhibitor is released.
C)Wounded tissue is sealed off to prevent the pathogen from moving through the plant.
D)Hydrogen peroxide is produceD.
E)Nitric oxide is produced.

Question 35

The plant alkaloid ricin is nontoxic inside castor beans,but becomes active when digested by an animal.The toxic form of ricin kills by

A)inactivating the animal's immune system.
B)over stimulating the animal's heart rate.
C)inactivating ribosomes needed for translation.
D)binding to RNA polymerase.
E)releasing cyanidE.

Question 36

In order to eat cassava from the Manihot plant safely,how does the plant have to be processed?

A)The roots must be ground into a fine flour.
B)The seeds must be removed from the fruits.
C)The leaves must be pickled.
D)The outer layers of the root have to be scrubbed off.
E)The cassava must be boiled for 10 hours.

Question 37

Which category of plant second metabolites includes stimulates like caffeine,nicotine,and cocaine?

A)tannins
B)alkaloids
C)phenolics
D)cyanogenic glycosides
E)terpenes

Question 38

Which of the following is not a method plants use to combat invaders?

A)silica crystals in certain tissues
B)trichomes on surfaces
C)thorns
D)tough bark
E)guard cells

Question 39

Which of the following statements about the pathogen-specific response is true?

A)The pathways involved always trigger the hypersensitive response.
B)The pathogen is recognized by its avr gene product.
C)There is never a gene-for-gene response.
D)If the R gene product is not triggered,no disease will occur.
E)Avr and R gene pairs have been cloned in species pathogenized by microbes,fungi,and insects.

Question 40

Taxol is a secondary metabolite from the bark of the Pacific yew tree that was found to be effective in fighting what human disease?

A)diabetes
B)breast cancer
C)indigestion
D)headaches
E)high blood pressure

Question 41

Choose the letter of the best match from the following:
A.avr
B.HR
C.PR
D.R
E.SAR
A pathogenesis-related gene.

Question 42

Choose the letter of the best match from the following:
A.avr
B.HR
C.PR
D.R
E.SAR
The hypersensitive response.

Question 43

Choose the letter of the best match from the following:
A.avr
B.HR
C.PR
D.R
E.SAR
Systematic acquired resistance.

Question 44

Choose the letter of the best match from the following:
A.avr
B.HR
C.PR
D.R
E.SAR
A pathogenic organism's gene that responds to the product of a plant resistance gene.

Question 45

Choose the letter of the best match from the following:
A.avr
B.HR
C.PR
D.R
E.SAR
A plant resistance gene.