Deck 21: Plant Structure and Function

Question 1

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.

Answer 1

B
Explanation: Short day/long night plants bloom when the length of continuous darkness is greater than a certain threshold.

Question 2

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

Answer 2

C
Explanation: Auxin migrates from one side of a leaf or stem in response to light, and is responsible for plant responses to light levels. Phytochrome detects day and night length.

Question 3

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

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

Answer 3

A
Explanation: Abscisic acid is required to maintain dormancy, and as long as levels of the hormone remain high, dormancy is maintained. As the levels of abscisic acid gradually fall throughout the winter, dormancy is broken, and growth resumes from the bud.

Question 4

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 5

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 6

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

Question 7

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 8

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 9

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 10

Flowering in most plants is triggered by

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

Question 11

Plant hormones

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

Question 12

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 13

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 14

A long day/short night plant would most likely

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

Question 15

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 16

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 17

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 upwards.
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.

Question 18

Which of the following plant hormones promotes cell division?

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

Question 19

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 20

Plant growth in response to an environmental stimulus is called

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

Question 21

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 22

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 23

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

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

Question 24

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

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

Question 25

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 26

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

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

Question 27

Production of cloned plants by using pollen is called

A) tissue culture.
B) anther culture.
C) clonal culture.
D) meristem culture.
E) genetic engineering.

Question 28

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 29

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 30

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

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

Question 31

Plants undergo an alternation of generations. The _______ produces spores, which develop into the ______.

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

Question 32

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 33

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 than the original plant.
D) are always virus-free.
E) cannot undergo asexual reproduction.

Question 34

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 35

The microspores develop into microgametophytes in the

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

Question 36

Because tomatoes contain seeds they are classified as a(n)

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

Question 37

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 38

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 39

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 40

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

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

Question 41

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

Question 42

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

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

Question 43

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

Question 44

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

Question 45

Long day/short night plants bloom when the night length is greater than a critical length.

Question 46

The aging process in plants is known as _______.

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

Question 47

Gametophytes of flowering plants are produced within the flower.

Question 48

An incomplete flower may lack a carpel.

Question 49

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

Question 50

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 51

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

Question 52

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

A) Meristem tissue is virus 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

A root growing into the Earth is exhibiting negative gravitropism.

Question 54

During pollen grain germination the two cells will develop into the ______ and _______.

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