Deck 27: Reproduction of Flowering Plants

Question 1

An angiosperm megagametophyte with 110 cells would be a highly unusual specimen,because the flowering plant typically has a megagametophyte consisting of

A) one pollen grain.
B) a pollen tube.
C) an embryo sac with eight haploid nuclei.
D) microspores.
E) a megasporangium and the cells within it.

Answer 1

C

Question 2

Which sequence represents the correct order of events (from earliest to latest)in the reproduction of angiosperms with regard to the egg?

A) Meiosis $\rightarrow$ egg formation $\rightarrow$ fertilization
B) Meiosis $\rightarrow$ fertilization $\rightarrow$ egg formation
C) Egg formation $\rightarrow$ fertilization $\rightarrow$ meiosis
D) Fertilization $\rightarrow$ meiosis $\rightarrow$ egg formation
E) Egg formation $\rightarrow$ meiosis $\rightarrow$ fertilization

Answer 2

Meiosis $\rightarrow$ egg formation $\rightarrow$ fertilization

Question 3

Which sequence represents the correct order of events in female gametophyte development?

A) Megagametophyte $\rightarrow$ megasporocyte $\rightarrow$ megaspore
B) Megagametophyte $\rightarrow$ megaspore $\rightarrow$ megasporocyte
C) Megasporocyte $\rightarrow$ megaspore $\rightarrow$ megagametophyte
D) Megaspore $\rightarrow$ megasporocyte $\rightarrow$ megagametophyte
E) Megaspore $\rightarrow$ megagametophyte $\rightarrow$ megasporocyte

Answer 3

Megasporocyte $\rightarrow$ megaspore $\rightarrow$ megagametophyte

Question 4

Which cells do not participate in double fertilization in apples?

A) Tube cells
B) Synergids
C) Eggs
D) Central cells
E) Antipodal cells

Question 5

Perfect and imperfect flowers differ from each other in that perfect flowers have all four types of flower parts but imperfect flowers are missing either

A) stamens or petals.
B) sepals or carpels.
C) stamens or carpels.
D) petals or sepals.
E) None of the above

Question 6

In flowering plants,the only structure to which pollen is directly transferred is the

A) style.
B) stigma.
C) ovary.
D) ovule.
E) micropyle.

Question 7

A newly discovered plant is thought to be wind-pollinated due to its exposure to regular,strong wind in spring and the lack of insect pollinators in its habitat.The presence of which of the following would confirm this assumption?

A) Extra flower parts
B) Smooth stigmas
C) Large quantities of pollen
D) Bloom during cold weather
E) Pollination before the opening of the flower bud

Question 8

Which sequence represents the correct order of events (from earliest to latest)in the reproduction of angiosperms,with regard to pollen and seed?

A) Pollination $\rightarrow$ seed dispersal $\rightarrow$ pollen formation
B) Pollen formation $\rightarrow$ pollination $\rightarrow$ seed dispersal
C) Seed dispersal $\rightarrow$ pollen formation $\rightarrow$ pollination
D) Seed dispersal $\rightarrow$ pollination $\rightarrow$ pollen formation
E) Pollen formation $\rightarrow$ seed dispersal $\rightarrow$ pollination

Question 9

The embryo sac is also called the

A) megaspore.
B) megasporangium.
C) megasporocyte.
D) megasporophyll.
E) megagametophyte.

Question 10

The two cells in a mature pollen grain are formed by

A) one meiotic division and one mitotic division.
B) two meiotic divisions and one mitotic division.
C) one meiotic division and two mitotic divisions.
D) two meiotic divisions and two mitotic divisions.
E) one meiotic division in which one of the four cells degenerates.

Question 11

In a flower,the microspores are formed in the

A) stamen.
B) style.
C) stigma.
D) ovule.
E) ovary.

Question 12

A benefit of sexual reproduction in plants is

A) the great number of progeny that result.
B) the ease of pollination.
C) that it creates genetic diversity.
D) that it creates a diploid plant from a haploid plant.
E) that it fosters widespread dispersal of progeny.

Question 13

Which statement about the stamen and the carpel or pistil is true?

A) The stamen has two named parts,whereas the pistil has three.
B) The stamen produces microgametophytes,whereas the carpel produces megagametophytes.
C) The carpel is yellow and the stamen is brown.
D) The stamens are long,whereas the pistil is short.
E) None of the above

Question 14

Suppose you are studying sexual reproduction in petunias.From what part of the flower should you extract material to study?

A) Petal
B) Ovule
C) Stigma
D) Sepal
E) Style

Question 15

In the mature embryo sac,the cells closest to where the pollen tube enters the ovule are the

A) polar nuclei.
B) synergids.
C) polar nuclei and synergids.
D) egg cell and polar nuclei.
E) egg cell and synergids.

Question 16

Which sequence represents the correct ordering of the events in the angiosperm life cycle?

A) Division of diploid zygote $\rightarrow$ pollen grain reaches a sporophyte $\rightarrow$ fertilization $\rightarrow$ production of pollen tube
B) Pollen grain reaches a sporophyte $\rightarrow$ production of pollen tube $\rightarrow$ fertilization $\rightarrow$ division of diploid zygote
C) Pollen grain reaches a sporophyte $\rightarrow$ division of diploid zygote $\rightarrow$ production of pollen tube $\rightarrow$ fertilization
D) Production of pollen tube $\rightarrow$ fertilization $\rightarrow$ division of diploid zygote $\rightarrow$ pollen grain reaches a sporophyte
E) Fertilization $\rightarrow$ pollen grain reaches a sporophyte $\rightarrow$ production of pollen tube $\rightarrow$ division of diploid zygote

Question 17

Which process is required for the production of an egg cell by a megasporocyte?

A) Meiosis followed by mitosis
B) Mitosis followed by meiosis
C) Several meiotic divisions only
D) Several mitotic divisions only
E) Several nuclear fusion events

Question 18

The microgametophyte of a flowering plant is

A) a flower.
B) an egg.
C) a pollen grain.
D) an anther.
E) the entire plant.

Question 19

After pollen is released from the anthers,the next event that takes place is

A) the fusion of the egg and sperm nuclei.
B) the transfer of pollen from the anther to the stigma.
C) the development of the two-celled pollen grain.
D) pollen germination and growth of the pollen tube
E) the division of the generative nucleus to produce two sperm nuclei.

Question 20

Which sequence represents the correct evolutionary order of pollination mechanisms,from earliest to latest?

A) Wind-pollinated plant $\rightarrow$ plant not needing liquid water $\rightarrow$ animal-pollinated plant
B) Plant not needing liquid water $\rightarrow$ animal-pollinated plant $\rightarrow$ wind-pollinated plant
C) Animal-pollinated plant $\rightarrow$ wind-pollinated plant $\rightarrow$ plant not needing liquid water
D) Animal-pollinated plant $\rightarrow$ plant not needing liquid water $\rightarrow$ wind-pollinated plant
E) Plant not needing liquid water $\rightarrow$ wind-pollinated plant $\rightarrow$ animal-pollinated plant

Question 21

If an insect chews through a flower,from outside to center,in what order will it eat the flower parts?

A) Sepal $\rightarrow$ carpel $\rightarrow$ petal
B) Petal $\rightarrow$ sepal $\rightarrow$ carpel
C) Carpel $\rightarrow$ petal $\rightarrow$ sepal
D) Carpel $\rightarrow$ sepal $\rightarrow$ petal
E) Sepal $\rightarrow$ petal $\rightarrow$ carpel

Question 22

If you wanted to breed a plant to introduce self-incompatibility,which mechanism would be least useful to target in your breeding program?

A) Pollen recognition proteins on the stigma
B) Pollen germination on the stigma
C) Pollen tube growth through the style
D) Sperm nuclei fusion with the egg
E) Introduction of novel S alleles

Question 23

Suppose you are stranded on a desert island that is bare of vegetation.One day at low tide you notice a coconut that was not present the day before.It was most likely dispersed from its parent plant by

A) monkeys.
B) wind.
C) fruit bats.
D) water.
E) birds.

Question 24

Angiosperm seeds develop

A) on a normal leaf.
B) in a fruit.
C) at the base of the flower next to sepals.
D) in the style.
E) in the stalk of the stamen.

Question 25

After pollination,which event is crucial for fertilization?

A) Sperm must swim to the egg and the polar nuclei.
B) Petals must close around the reproductive parts.
C) Meiosis must occur within the pollen grain.
D) A pollen tube must grow from the stigma to the ovule.
E) An insect must deliver pollen to the stigma.

Question 26

You are observing two plots of tobacco plants,one grown from seed that was the product of self-pollination,the other grown from seed that came from a cross.The latter,on average,performs better in terms of seed production due to

A) increased genetic diversity.
B) the occurrence of meiosis.
C) more successful pollination.
D) a lack of a need for pollination.
E) less energy being required than for self-pollination.

Question 27

A seed consists of a _______ embryo,a _______ endosperm,and a _______ seed coat.

A) diploid;triploid;diploid
B) haploid;triploid;diploid
C) diploid;triploid;haploid
D) diploid;diploid;diploid
E) haploid;diploid;haploid

Question 28

A scientist has perfected a technique for capturing individual cells during the process of reproduction.What will be captured along with one of the synergids just before fertilization?

A) Sperm cells
B) Generative nuclei
C) Tube nuclei
D) Pollen nuclei
E) Microspores

Question 29

What is the fate of the seven cells of the embryo sac?

A) All but one disintegrates upon fertilization.
B) Two become fertilized;the others degenerate.
C) Two become fertilized;the others fuse to form endosperm.
D) All are involved in nuclear fusion events.
E) All become part of the seed tissue.

Question 30

Some wind-dispersed seeds use _______ to help them travel.

A) animal fur
B) bird feathers
C) structures that catch the wind
D) velcro-like attachment structures
E) air sacs

Question 31

The endosperm is formed by a fusion of the _______ and _______.

A) egg nucleus;a sperm nucleus
B) egg nucleus;two sperm nuclei
C) synergid nuclei;a sperm nucleus
D) polar nuclei;a generative nucleus
E) polar nuclei;a sperm nucleus

Question 32

Which statement about a genetically self-incompatible species of plant is most likely false?

A) It has many S alleles.
B) Its self pollen germinates poorly.
C) Its self pollen tubes grow poorly.
D) Its self pollen attaches poorly to pollinators.
E) Its recognition of self pollen involves proteins.

Question 33

In flowering plants,fertilization occurs

A) where pollen lands on the stigma.
B) where the pollen tube germinates.
C) inside the pollen tube.
D) at the base of the embryo sac.
E) inside the seed.

Question 34

After fertilization of the egg,the integument of the megasporangium develops into the

A) cotyledons.
B) embryo.
C) endosperm.
D) fruit.
E) seed coat.

Question 35

The advantage of self-pollination in plants is that

A) it results in increased genetic recombination.
B) meiosis can occur.
C) it increases the chances of successful fertilization.
D) no flowering is needed.
E) only asexual reproduction is necessary.

Question 36

Double fertilization in flowering plants results in the production of

A) two diploid embryos.
B) one diploid embryo and a diploid endosperm.
C) two diploid embryos and a haploid endosperm.
D) one diploid embryo and a triploid endosperm.
E) two diploid embryos and a diploid seed coat.

Question 37

The integuments of the ovule develop into the _______,and the carpels ultimately become the wall of the _______.

A) seed coat;fruit
B) cotyledons;endosperm
C) cotyledons;seed coat
D) endosperm;seed coat
E) cotyledons;fruit

Question 38

The egg can be fertilized by

A) one tube nucleus.
B) one sperm cell.
C) two antipodal nuclei.
D) one generative nucleus.
E) two synergid nuclei.

Question 39

A newly discovered fruit has a thick,sweet flesh that is relished by bears.This fruit wall is

A) nourishing the embryo.
B) attracting seed eaters.
C) attracting pollinators.
D) attracting seed dispersers.
E) ensuring that the seeds fall close to the parent plant.

Question 40

The seeds of a new kind of corn germinate while attached to the cob,which is unusual.How do these seeds differ from normal?

A) They are not dispersed.
B) They contain reserves.
C) They are released from the fruit.
D) They do not become dormant.
E) They are protected from animal predators.

Question 41

A horticulturalist who wants to induce flowering in a crop of short-day plants should carry out the induction

A) in the spring.
B) when day length is below a critical maximum.
C) in midsummer.
D) when day length is above a critical maximum.
E) throughout the summer.

Question 42

The ability of plants to measure night length was determined by experiments in which

A) plants were grown in 12 hours of darkness alternating with 12 hours of light.
B) plants were grown in continuous light.
C) plants were grown in dark periods that were interrupted with brief pulses of light.
D) flowering was measured in plants of different ages that had been placed on the same light-dark schedule.
E) plants were grown in a 24-hour cycle in which the length of the light period was increased gradually.

Question 43

An SDP plant flowers when

A) the ratio of P_fr to P_r is sufficiently high.
B) the ratio of P_fr to P_r is sufficiently low.
C) the nights are sufficiently short.
D) enough far-red light has been absorbed.
E) P_fr equals P_r.

Question 44

A plant's transition to a flowering state is often marked by a(n)

A) increased rate of photosynthesis.
B) decrease in vegetative growth.
C) increase in root development.
D) decreased rate of respiration.
E) increase in lateral bud growth.

Question 45

In a short-day plant like cocklebur,which has a critical day length of 15 hours,flowering could be induced by _______ hours of light alternating with _______.

A) 12;12 hours of darkness
B) 16;8 hours of darkness
C) 14;8 hours of darkness
D) 8;8 hours of darkness
E) 15;9 hours of darkness,interrupted by one short burst of white light

Question 46

Which of the following would most likely happen if a repressor to APETALA1 were overexpressed in shoot apical meristems throughout the plant?

A) The plant would flower profusely regardless of environmental conditions.
B) The plant would flower only in the appropriate environmental conditions.
C) The plant would flower only if it were also provided with the products of wild-type organ identity genes.
D) The plant would flower only if it were also provided with phytochrome.
E) The plant would not flower regardless of environmental conditions.

Question 47

To stage long-day plants so they will produce blooms for a flower show,what can a greenhouse manager provide to the plants to prevent flowering?

A) A long,uninterrupted period of darkness
B) A period of daylight interrupted by a dark period
C) A period of daylight interrupted by a prolonged period of red light
D) A period of darkness interrupted by a period of far-red light
E) A period of daylight interrupted by a brief period of red light

Question 48

Technically,short-day plants flower when the _______ period _______ a critical maximum.

A) night;equals
B) day;equals
C) day;is longer than
D) day;is shorter than
E) night;is shorter than

Question 49

A vegetative meristem must _______ in order to begin switching to floral development.

A) experience determinate growth
B) be influenced by meristem identity genes
C) experience indeterminate growth
D) be influenced by other meristems
E) None of the above

Question 50

You are asked to identify the version of florigen found in carnivorous sundew plants.You decide to start by using biochemical methods to separate different macromolecules to isolate the florigen,because it is a(n)

A) RNA molecule.
B) nucleotide.
C) DNA molecule.
D) protein.
E) lipid.

Question 51

A conifer is found with homologs of the genes that determine the location of floral parts in the flower.These are homologs of _______ genes.

A) meristem identity
B) whorl
C) flowering time
D) apical
E) floral organ identity

Question 52

A new kind of mustard is found to flower with any length of day or night as long as it is at least two months old.What kind of plant is this?

A) Short-day plant
B) Long short-day plant
C) Long-day plant
D) Short long-day plant
E) None of the above

Question 53

For plants that flower in response to photoperiodic stimuli,the most critical determinant in the light-dark cycle is the

A) temperature.
B) length of the dark period for short-day plants and length of the light period for long-day plants.
C) length of the light period for short-day plants and length of the dark period for long-day plants.
D) length of uninterrupted dark.
E) length of uninterrupted light.

Question 54

Experiments have shown that when a short-day plant (SDP)and a long-day plant (LDP)are grafted together and the SDP is exposed to a photoperiod that causes it to flower,the LDP also flowers.This suggests that a specific flower-initiating hormone is produced in plants.A properly controlled experiment would also

A) include grafting together the two plants without inducing the SDP.
B) lengthen the SDP photoperiod.
C) include exposing only the LDP plant to P_fr light.
D) shorten the SDP photoperiod.
E) include an LDP photoperiod.

Question 55

Even if a plant receives an inductive stimulus that would normally lead to flowering,the flowering may be prevented by a quick removal of the

A) floral meristem.
B) vegetative apical meristem.
C) stems.
D) leaves.
E) roots.

Question 56

When a vegetative apical meristem ceases production of leaves and axillary buds and instead produces structures such as bracts,it has become a(n)

A) axillary meristem.
B) inflorescence.
C) inflorescence meristem.
D) leaf.
E) branch.

Question 57

Flowers can occur singly or in an orderly cluster known as a(n)

A) inflorescence.
B) flower cluster.
C) head.
D) grouping.
E) daisy chain.

Question 58

After an apical meristem has been redirected toward developing into a floral meristem,_______ are responsible for further refinement of the floral development pathway.

A) unknown hormones
B) light signals
C) floral organ identity genes
D) other,more mature floral meristems
E) All of the above

Question 59

Which of the following is not a pattern of plant flowering?

A) Annual
B) Biennial
C) Perennial
D) Diapausal
E) Both a and c

Question 60

Short-day plants bloom

A) in the spring.
B) in the fall.
C) in the summer.
D) only after the second year of life.
E) in the spring or in the fall.

Question 61

Asexual reproduction is the best strategy for plants

A) that are well adapted to a stable environment.
B) as winter approaches.
C) when new genes must be introduced.
D) that have underground stems.
E) that have low seed production during a particular season.

Question 62

You are given an extract of DNA from vernalized winter wheat seeds and asked to decide if vernalization has gone on long enough for flowering to occur.In order to make this judgment,you would examine an extract of DNA under an electron microscope and look for

A) signs of degradation.
B) contamination with lipids.
C) modified chromatin.
D) extra protein coating the DNA.
E) increased expression of FLC protein.

Question 63

A clone of white potatoes may be derived from underground

A) tubers.
B) stolons.
C) rhizomes.
D) bulbs.
E) root suckers.

Question 64

You have discovered that your neighbor's bamboo plants are spreading into your yard.To stop this,what part of the plant must be killed or pruned?

A) Rhizomes
B) Tubers
C) Corms
D) Stolons
E) Leaves

Question 65

Self-pollination results in progeny that

A) are identical to the parent.
B) are somewhat different from the parent because mutations are common.
C) can express only alleles that were present in the parent.
D) may be heterozygous in a locus where the parent is homozygous.
E) may be as varied as progeny resulting from cross-pollination.

Question 66

Vegetative plant parts called _______ are short,vertical stems modified for asexual reproduction.

A) rhizomes
B) tubers
C) bulbs
D) stocks
E) stolons

Question 67

If you wanted to produce a mutant plant that flowers in excess,which genetic manipulation would be the best choice?

A) Delete AP1 gene.
B) Reduce FD expression.
C) Reduce FT expression.
D) Overexpress AP1.
E) Inhibit CO action.

Question 68

Which of the following is not one of the mechanisms used by plants that flower independently of an external stimulus?

A) An internal clock
B) An unknown internal signal
C) A genetic program insensitive to the environment
D) A signal pathway dependent on bud position
E) A photoreceptor

Question 69

Which sequence represents the correct chronological order in which genes interact in the flowering pathway?

A) FT,CO,AP1
B) FT,AP1,CO
C) CO,FT,AP1
D) CO,AP1,FT
E) AP1,CO,FT

Question 70

Suppose that a certain angiosperm grows both in Colorado and in New England.The Colorado plants reproduce asexually,while those in New England reproduce sexually.What can be inferred about the two environments in which these plants grow?

A) The Colorado environment is more stable.
B) The New England environment is more stable.
C) The Colorado environment provides more nutrients.
D) The New England environment contains more pollinators.
E) No conclusion can be inferred from this information.

Question 71

Flowering is known to be triggered by

A) phytochrome.
B) NO.
C) ethylene.
D) abscisin.
E) florigen.

Question 72

An entire grove of aspens will usually change color simultaneously in the fall.The reason for this is that all of the trees have developed from _______ that were produced _______.

A) seeds;sexually
B) clones;asexually
C) seeds;asexually
D) clones;sexually
E) different species;in the same area

Question 73

What would be the most likely effect of too little expression of CONSTANS (CO)?

A) Flowering would occur even in the absence of appropriate environmental signals.
B) Flowering would be less likely to occur.
C) Plants would be more likely to respond to vernalization.
D) Plants would be less likely to respond to vernalization.
E) There would be no effect.

Question 74

A newly grown lemon plant is placed next to the parent plant that had produced the seed.The two plants prove to be identical,indicating it was an apomictic seed.What else can be said about this seed?

A) It was produced when two sperm fertilized one egg.
B) It developed from one egg alone.
C) It was the result of parental self-fertilization.
D) It formed without fertilization.
E) It was homozygous for most genetic traits.

Question 75

What could be expected from a mutant plant that lacks expression of the FLOWERING LOCUS C (FLC)gene?

A) Earlier flowering than in the wild type
B) More leaves than in the wild type
C) More flower petals per flower than in the wild type
D) Fewer leaf hairs than in the wild type
E) None of the above

Question 76

Which protein is most directly and physically involved in turning on gene expression for the transition to flower production?

A) FT
B) FD
C) CO
D) AP1
E) Both a and b

Question 77

A horticulturalist who is producing strawberry plants that are clones of their parent is relying on which biological process?

A) Cross-hybridization
B) Forced seed germination
C) Apomixis
D) A runner system
E) Vernalization

Question 78

A new variety of oats that requires vernalization must _______ before it will produce seeds.

A) be exposed to cold
B) have sufficient soil calcium
C) experience a minimal day length
D) have sufficient moisture for a minimum period
E) experience one full year of growth

Question 79

Winter wheat can be planted in the spring for fall harvest if it is

A) sprayed with gibberellins.
B) vernalized.
C) planted under a full moon.
D) stored in the dark for 50 days.
E) soaked in water.

Question 80

What kind of enzyme might directly affect flowering?

A) One that degrades nucleic acid
B) One that degrades protein
C) One that degrades carbohydrate
D) One that degrades lipid
E) None of the above