Deck 21: Plant Responses and Reproduction

Question 1

Auxin produced by which portion of the plant is responsible for the development of fruit?

A) apical meristem
B) seeds
C) vascular cambium
D) root
E) lateral bud

Answer 1

B
Explanation: Auxin promotes fruit growth and prevents it from falling off the plant. Trees can be sprayed with auxin to promote growth and prevent mature fruit from falling to the ground.

Question 2

Which of the following events will occur if gibberellins are applied to barley?

A) The lateral meristems will be inhibited and the plant will grow upward.
B) The starchy endosperm will be broken down and converted into sugars for the developing embryo.
C) The stomata will remain closed to avoid the loss of water from the plant.
D) Plant growth is accelerated by promoting cell division.
E) Cellulase is produced, which will stimulate the breakdown of the cellulose in the cell walls.

Answer 2

B
Explanation: Gibberellins are the hormones responsible for activating the genes that code for amylase. Amylase will then in turn break down starch and release the sugars as a source of energy for embryonic growth.

Question 3

Plant hormones are

A) receptor proteins.
B) chemical signaling molecules.
C) produced only in the apical meristem.
D) produced both in the apical meristem and the vascular cambium.
E) proteins.

Answer 3

B
Explanation: Plant hormones may be produced from many different cell types, and cause plants to respond to environmental stimuli. Plant hormones are most commonly composed of organic chemical compounds.

Question 4

You wish to change the growth pattern of the shrubs in your yard to give them a fuller, more bushy appearance. This could be accomplished by

A) pruning the shoot tip.
B) pruning the lateral buds.
C) pruning the lateral buds and applying gibberellins.
D) applying auxin to the roots.
E) pruning the shoot tip and applying auxin to the shoot.

Question 5

Auxin causes bending in stems and roots by

A) causing cell elongation.
B) preventing cell elongation.
C) breaking down cell walls.
D) causing cell shrinkage.
E) inhibiting lateral bud growth.

Question 6

Short-day long-night) plants

A) bloom after a certain length of continuous daylight.
B) bloom after a certain length of continuous darkness.
C) bloom only at night.
D) use other environmental stimuli to trigger flowering.
E) bloom only during the day.

Question 7

When a plant is experiencing water stress,

A) auxin will shut down vessel elements.
B) gibberellins will stimulate growth of root hairs.
C) abscisic acid will stimulate closure of stomata.
D) ethylene will increase water flow in vessel elements.
E) cytokinins will stimulate elongation of stems and growth of new leaves.

Question 8

A farmer wishes to force a normal plant to maintain a dwarf size. Which of the following plant hormones might she apply?

A) auxin
B) cytokinin
C) ethylene
D) abscisic acid
E) gibberellins

Question 9

Monocot seeds differ from eudicot seeds because in monocot seeds

A) the cotyledons absorb the stored food of the endosperm.
B) the endosperm is retained.
C) there are two cotyledons instead of one.
D) there is no seed coat.
E) the endosperm develops into the embryo.

Question 10

Which of the following is not an effect of gibberellins?

A) stem elongation between nodes
B) cell elongation
C) breaking of dormancy
D) ripening of fruit
E) excessive stem elongation

Question 11

A long-day short-night) plant would most likely bloom only

A) in the fall.
B) in the spring.
C) in the summer.
D) at night.
E) during the day.

Question 12

Ethylene stimulates fruit ripening by stimulating

A) the transport of hydrogen ions out of the cell.
B) the production of amylase for starch breakdown.
C) bacterial activity which softens the fruit.
D) cellulase to break down cellulose in cell walls.
E) mitosis of cells within the fruit to promote fruit growth.

Question 13

Which of the following plant hormones promotes cell division?

A) cytokinins
B) auxin
C) gibberellins
D) abscisic acid
E) ethylene

Question 14

Plants detect the presence of light using _____, whereas day length is detected using _____.

A) auxin; gibberellin
B) phytochrome; auxin
C) auxin; phytochrome
D) phytochrome; gibberellin
E) gibberellin; auxin

Question 15

A gardener wants to stimulate branching but keep the apical meristem intact so that the plants will also grow in height. What hormone should be applied?

A) auxin
B) cytokinin
C) ethylene
D) abscisic acid
E) gibberellins

Question 16

Flowering in most plants is triggered by

A) auxin migration.
B) night length.
C) day length.
D) gibberellin production.
E) negative phototropism.

Question 17

A winter bud begins winter with an amount of abscisic acid to maintain dormancy. Dormancy is broken in the spring because of an)

A) gradual reduction in abscisic acid over winter.
B) increase of abscisic acid production by the meristem within the bud.
C) increase in cytokinin in the leaves.
D) gradual reduction of auxin in the shoot tip.
E) gradual increase in ethylene production by the meristem within the bud.

Question 18

Plant reproduction by tissue culture differs from reproduction by meristem culture because

A) plants produced by meristem culture are clones, whereas tissue culture does not produce genetically identical plants.
B) tissue culture requires cells from a plant's root system, whereas any cell of a plant may be used for meristem culture.
C) tissue culture propagation produces clonal plants, whereas meristem culture produces plants that may be genetically different.
D) tissue culture produces plants that are virus-free, whereas plants produced by meristem culture may not be virus-free.
E) meristem culture requires removal of the plant cell walls, whereas tissue culture does not.

Question 19

Plant growth in response to an environmental stimulus is called

A) apical dominance.
B) a tropism.
C) senescence.
D) a photoperiod.
E) dormancy.

Question 20

Peaches may be ripened at home by enclosing them in a paper bag. This is due to the production of which hormone?

A) auxin
B) cytokinin
C) ethylene
D) abscisic acid
E) gibberellins

Question 21

Which of the following is not a function of the flower in an angiosperm?

A) producing fruit
B) protection of the gametophyte
C) attracting pollinators
D) producing spores
E) supporting the plant

Question 22

An incomplete flower may lack a carpel.

Question 23

The microspores develop into microgametophytes in the

A) anther.
B) filament.
C) stigma.
D) style.
E) ovary.

Question 24

Phytochrome red P_r) differs from phytochrome far-red P_fr) in that

A) P_r is converted to P_fr during the nighttime.
B) P_r is converted to P_fr by absorbing sunlight.
C) P_fr is converted to P_r by absorbing sunlight.
D) P_fr is converted to P_r by absorbing far-red light that is available at dusk.
E) P_r is converted to P_fr by absorbing far-red light, which is available only during full daylight.

Question 25

The products of double fertilization in the _____ are a 2n ____ and a 3n _____.

A) ovary; zygote; endosperm
B) ovary; endosperm; zygote
C) anther; zygote; endosperm
D) anther; endosperm; zygote
E) stigma; endosperm; zygote

Question 26

Some citizens are concerned about the use of genetically modified plants because they

A) are better for the environment.
B) may harm the environment.
C) are less nutritious than the original plant.
D) are genetically identical.
E) do not grow as well as the original plant.

Question 27

Which of the following is an incorrect match of structure to function?

A) sepal - protection of flower
B) filament - produces pollen
C) petal - attracts pollinator
D) ovary - contains female gametophyte
E) stigma - allows pollen to adhere

Question 28

Because tomatoes contain seeds they are classified as a

A) dry fruit.
B) pome.
C) stone fruit.
D) berry.
E) legume.

Question 29

Since plant sperm are nonflagellated, how do they reach the ovule from the stigma?

A) They swim in water.
B) They are delivered by a pollen tube.
C) They are carried on air currents.
D) They are delivered by insects.
E) The ovules are delivered to the stigma.

Question 30

Which of the following is not a method of asexual reproduction in plants?

A) rhizomes
B) stolons
C) suckers
D) tubers
E) dry fruits

Question 31

A plant that is dioecious is incapable of which of the following?

A) cross-pollination
B) double fertilization
C) self-pollination
D) gametophyte production
E) pollen production

Question 32

An advantage of using genetically modified plants is that they

A) are genetically identical to the parent plant.
B) grow much more quickly.
C) may possess superior characteristics to the original plant.
D) are always virus-free.
E) cannot undergo asexual reproduction.

Question 33

Which of the following structures may be missing in a bisexual flower?

A) carpels
B) stamens
C) sepals
D) ovules
E) anthers

Question 34

Plants undergo an alternation of generations. This means that the _____ produces spores, which develop into the _____.

A) sporophyte; gametophyte
B) gametophyte; sporophyte
C) sporophyte; seeds
D) flowers; gametophyte
E) sporophyte; flowers

Question 35

A fleshy fruit is more likely to use which of the following methods of seed dispersal?

A) eaten by animals and seeds passed through feces
B) blown by wind
C) stuck to fur of mammal and carried
D) fruit bursts when mature, spreading seeds outward
E) drop and remain near parent plant

Question 36

A nursery wishes to produce a large number of carrot plants for sale in the spring. The nursery will most likely use which technique?

A) tissue culture
B) hybridization
C) cuttings
D) anther culture
E) meristem culture

Question 37

In a eudicot seed, the zygote becomes the _____, while the _____ is derived from the endosperm.

A) embryo; seed coat
B) cotyledons; embryo
C) embryo; cotyledon
D) embryo; stored food
E) stored food; seed coat

Question 38

Plants undergo an alternation of generations. The _____ produces gametes that fuse to produce a new _____.

A) sporophyte; gametophyte
B) gametophyte; sporophyte
C) gametophyte; flower
D) flowers; gametophyte
E) sporophyte; flower

Question 39

Which of the following does not represent a possible use for genetically modified crops?

A) vaccine production
B) improved yield
C) herbicide resistance
D) mass reproduction by asexual means only
E) improved nutritional value

Question 40

Plants with both female and male flowers on the same plant are called

A) complete.
B) incomplete.
C) monoecious.
D) dioecious.
E) bisexual.

Question 41

During pollen grain germination, the two cells will develop into the _____ and _____.

A) pollen tube and sperm
B) pollen tube and egg
C) ovule and sperm
D) fruit and seeds
E) pollen tube and zygote

Question 42

The aging process in plants is known as

A) senescence.
B) dormancy.
C) abscission.
D) apical dominance.
E) gravitropism.

Question 43

Alternation of generations means that a diploid sporophyte produces haploid spores by meiosis, and a haploid gametophyte produces gametes by mitosis.

Question 44

Cytokinins may help promote the growth of new plants in tissue culture.

Question 45

Gametophytes of flowering plants are produced within the flower.

Question 46

Which plant hormone is responsible for breaking the dormancy cycle in plants?

A) gibberellins
B) auxins
C) abscisic acid
D) ethylene
E) cytokinins

Question 47

The application of auxin to a seed may cause it to germinate.

Question 48

In order for senescence to be prevented, which hormone needs to be present in the plant?

A) gibberellins
B) cytokinins
C) abscisic acid
D) ethylene
E) auxin

Question 49

A root growing into the Earth is exhibiting negative gravitropism.

Question 50

During germination, which part of the seed exhibits negative gravitrophism?

A) embryonic shoot
B) cotyledon
C) seed coat
D) root system
E) embryo

Question 51

A monocot seed consists of a seed coat, two cotyledons, an embryo, and an endosperm.

Question 52

What is the main advantage of using the meristem culture technique over natural methods of asexual reproduction?

A) Meristem tissue can be disease-free.
B) Meristem tissue is the most abundant tissue on the plant.
C) This technique produces exact clones.
D) Other culture techniques are not accepted by the public.
E) This technique is relatively inexpensive to do.

Question 53

In what way would a grower in the grape industry use gibberellins?

A) Gibberellins would increase the size of the fruits.
B) Gibberellins would prevent the plants from getting fungal infections.
C) Gibberellins would help break down the starches found in the fruits, making them sweeter.
D) Gibberellins would promote an increase in the rate at which the plants produce fruit.
E) Gibberellins would make the plants resistant to parasitic infections.

Question 54

During germination, which cellular structure will exhibit positive gravitrophism and grow downward?

A) embryonic root
B) embryonic shoot
C) cotyledon
D) shoot
E) seed nucleus

Question 55

Which hormone is involved in a plant dropping the lower leaves as it grows taller?

A) cytokinins
B) gibberellins
C) auxin
D) ethylene
E) abscisic acid

Question 56

What is the role of auxin in regards to plant growth?

A) Auxin softens the cell wall enabling the cells to grow.
B) Auxin disintegrates the cell wall in a plant allowing two cells to enlarge into one.
C) Auxin will stunt plant growth.
D) Auxin will increase the rate at which plant cells can grow.
E) Auxin will decrease the rate at which plant cells grow.

Question 57

The application of abscisic acid to a plant may prevent fruit maturation.

Question 58

A friend complains that all of her houseplants have bent stems. You examine the plants and find that their stems all curve toward the light. What would you recommend to your friend to correct the problem?

A) Turn each plant occasionally toward the light.
B) Apply an auxin to the shady side of the stems.
C) Water the plants more frequently.
D) Apply gibberellins to the bases of the stems.
E) Repot the plants.

Question 59

If ethylene is applied to a bushel of apples, what is most likely to occur?

A) The fruit will ripen.
B) The apple seeds will go into a state of dormancy.
C) The seeds will germinate.
D) The fruit will retain its water for a longer period of time.
E) The apple stem will fall off.

Question 60

Plants are naturally able to reproduce asexually because they contain meristematic tissue.

Question 61

What is the actual site of double fertilization?

A) ovule
B) ovary
C) embryo sac
D) anther
E) stigma

Question 62

Which of the following is not an advantage of genetically engineered plants?

A) decreased yield
B) herbicide resistance
C) salt tolerance
D) drought tolerance
E) disease protection

Question 63

Which of the following pharmaceutical products can be produced by genetically modified plants?

A) antigens
B) antibodies
C) hormones
D) therapeutic proteins
E) All of these are produced by plants.

Question 64

Which cellular structure enables a root cell to grow downward?

A) amyloplast
B) chromoplast
C) auxin
D) chloroplast
E) nucleus

Question 65

An increase in the amount of protein produced is an advantage of using plants to develop products for the pharmaceutical industry.

Question 66

Which fruit is most likely to be dispersed by the wind?

A) dandelion
B) apples
C) walnut
D) cocklebur
E) cherry

Question 67

Which of the following structures is used by strawberry plants during asexual reproduction?

A) stolon
B) rhizome
C) tuber
D) corm
E) ovary