Deck 38: Reproduction in Flowering Plants

Question 1

The embryo sac is also called the

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

Answer 1

E

Question 2

Which statement about double fertilization is not true?

A) It is found in most angiosperms.
B) It takes place in the microsporangium.
C) One of its products is a triploid nucleus.
D) One sperm nucleus fuses with the egg nucleus.
E) One sperm nucleus fuses with two polar nuclei.

Answer 2

B

Question 3

In order for a megasporocyte to turn into an egg cell, which of the following processes are required?

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

Answer 3

A

Question 4

Which of the following is the correct order of events for female gametophytes?

A) Megagametophyte, megasporocyte, megaspore
B) Megagametophyte, megaspore, megasporocyte
C) Megasporocyte, megaspore, megagametophyte
D) Megaspore, megasporocyte, megagametophyte
E) Megaspore, megagametophyte, megasporocyte

Question 5

The suspensor

A) gives rise to the embryo.
B) is heart-shaped in eudicots.
C) separates the two cotyledons of eudicots.
D) ceases to elongate early in embryonic development.
E) is larger than the embryo.

Question 6

The typical angiosperm female gametophyte

A) is called a microspore.
B) has eight nuclei.
C) has eight cells.
D) is called a pollen grain.
E) is carried to the male gametophyte by wind or animals.

Question 7

Apomixis involves

A) sexual reproduction.
B) complete meiosis.
C) fertilization.
D) a diploid embryo.
E) no production of a seed.

Question 8

Meiosis occurs within the

A) petal.
B) ovule.
C) stigma.
D) sepal.
E) pollen grain.

Question 9

Which statement about vernalization is not true?

A) It decreases the abundance of an inhibitor of flowering.
B) Vernalization involves exposure to cold temperatures.
C) It only occurs in crop plants such as cereals.
D) In the vernalized state, the synthesis of FLC protein is inhibited.
E) If winter wheat is not exposed to cold, it will not flower.

Question 10

Sexual reproduction in angiosperms

A) is by way of apomixis.
B) requires the presence of petals.
C) can be accomplished by grafting.
D) gives rise to genetically diverse offspring.
E) cannot result from self-pollination.

Question 11

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

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

Question 12

Which of the following does not participate in asexual reproduction?

A) Stolon
B) Rhizome
C) Zygote
D) Tuber
E) Corm

Question 13

Strawberries reproduce asexually through

A) cross-hybridization.
B) forced seed germination.
C) apomixis.
D) a runner system.
E) vernalization.

Question 14

Which statement about photoperiodism is not true?

A) It is related to the biological clock.
B) A phytochrome plays a role in the timing process.
C) It is based on measurement of the length of the night.
D) Some plants do not flower in response to photoperiod.
E) It is limited to plants.

Question 15

The megagametophyte of flowering plants consists of the

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

Question 16

Florigen is

A) produced in the leaves and transported to the apical bud.
B) produced in the roots and transported to the shoots.
C) produced in the coleoptile tip and transported to the base.
D) the same as gibberellin.
E) activated by prolonged (more than a month) high temperature.

Question 17

A benefit of sexual reproduction in plants is

A) the greater number of progeny that results.
B) ease of pollination.
C) the creation of new combinations of genes and diverse phenotypes.
D) that the haploid plant becomes diploid.
E) farther dispersal of progeny.

Question 18

In a flower, the microsporangia are found on the

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

Question 19

The gametophyte of a flowering plant is

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

Question 20

Pollination in angiosperms

A) always requires wind.
B) never occurs within a single flower.
C) always requires help by animal pollinators.
D) is also called fertilization.
E) makes most angiosperms independent of external water for reproduction.

Question 21

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

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

Question 22

As a pollen tube grows into the embryo sac, two _______ are delivered to one of the synergids.

A) sperm cells
B) generative nuclei
C) tube nuclei
D) pollen nuclei
E) microspores

Question 23

The egg can be fertilized by

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

Question 24

After pollination, which of the following events 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 25

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

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

Question 26

Which of the following is the "suspensor"?

A) The pollen tube
B) The organ supporting the ovule
C) The base of the flower
D) The narrow part of the embryo
E) The stalk of the stamen

Question 27

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 28

A flower that is wind-pollinated would be least likely to

A) have numerous anthers.
B) have sticky or feathery stigmas.
C) produce large numbers of pollen grains.
D) have a colorful corolla.
E) have unscented flowers.

Question 29

Pollination is the

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

Question 30

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 31

Which of the following is a distinguishing characteristic of all angiosperms?

A) Double cotyledons
B) Fleshy cotyledons
C) Seeds with nutrients
D) Double fertilization
E) Pollen production

Question 32

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

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

Question 33

In flowering plants, pollen is transferred to the

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

Question 34

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 35

The advantage of cross-fertilization in plants is

A) increased genetic recombination.
B) that meiosis can occur.
C) greater efficiency of pollination.
D) that no flowering is needed.
E) that it requires less energy to accomplish than self-fertilization.

Question 36

The advantage of self-fertilization in plants is

A) increased genetic recombination.
B) that meiosis can occur.
C) greater efficiency of pollination.
D) that no flowering is needed.
E) that only asexual reproduction is necessary.

Question 37

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 disintegrate.
C) Two become fertilized; the others fuse to form endosperm.
D) All are involved in nuclear fusion events.
E) They all become part of the seed tissue.

Question 38

Early in development, _______ initiates cell specialization in the embryo.

A) mitotic division of the zygote
B) uneven distribution of cytoplasm
C) absorption of food from the endosperm
D) seed germination
E) maturation of the fruit

Question 39

Plants with wind-pollinated flowers tend to have

A) colorful petals.
B) smooth stigmas.
C) large quantities of pollen.
D) large quantities of nectar.
E) pollination before the bud opens.

Question 40

Double fertilization results in the formation 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 41

Short-day plants usually flower

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

Question 42

The fruit generally develops from which part of the flower?

A) Petals
B) Sepals
C) Ovary
D) Stamens
E) Pedicel

Question 43

Which of the following is a characteristic of wind-dispersed seeds?

A) Abundant pollen
B) Hooked extensions
C) Fleshy fruit
D) Air chambers
E) A "parachute"

Question 44

Which of the following is not a category of flowering plants?

A) Annuals
B) Biennials
C) Perennials
D) Indeterminants
E) Both a and c

Question 45

In a short-day (long-night) plant with a critical day length of 15 hours, flowering would 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

In some eudicots, no distinct endosperm can be seen because the

A) embryo has digested the endosperm.
B) cotyledons have absorbed the endosperm.
C) seeds never produced an endosperm.
D) endosperm has become the seed coat.
E) fruit has incorporated the endosperm.

Question 47

Birds are good seed dispersal agents because

A) seed survival in bird guts is low.
B) the undigested seeds are deposited in a heap at the nesting sites.
C) the undigested seeds are deposited at various feeding sites.
D) the undigested seeds are deposited near the same plant that produced them.
E) the digested seeds are dispersed at feeding and nesting sites.

Question 48

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 49

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 the uninterrupted dark cycle.
E) length of the uninterrupted light cycle.

Question 50

Long-day plants will not flower if exposed to a long

A) night.
B) day interrupted by a dark period.
C) day interrupted by a prolonged period of red light.
D) night interrupted by a period of far-red light.
E) day interrupted by a brief period of red light.

Question 51

Which of the following does not serve to break dormancy and initiate seed germination?

A) Scarification by abrasion
B) Scarification by fire
C) Exposure to water
D) Abscisic acid
E) Growth promoters

Question 52

The loss of water from a developing seed causes it to

A) produce a root.
B) die.
C) be released from the fruit.
D) become dormant.
E) be protected from animal predators.

Question 53

The nutritious flesh of many fruits has the function of

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 54

Short-day plants bloom

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

Question 55

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 identity genes
D) other, more mature floral meristems
E) All of the above

Question 56

In the seed, nutrients for the seedling are generally stored as

A) monomers in solution.
B) monomers in fat storage.
C) a very concentrated, glass-like fluid.
D) cellular enzymes.
E) cellular organelles.

Question 57

Before becoming a flower, the 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 58

Which of the following is found in the highest concentration in dormant (inactive) buds and seeds?

A) Abscisic acid
B) Auxin
C) Cytokinin
D) Ethylene
E) Gibberellin

Question 59

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 60

Coconut fruits are dispersed by

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

Question 61

The transfer of pollen grains to the stigma is called _______.

Question 62

The production of French wine grapes (Vitis vinifera) that are resistant to plant lice was accomplished by

A) self-fertilization of resistant plants.
B) grafting the scion onto resistant plants' root stock.
C) recombinant DNA techniques using the resistance gene.
D) planting seeds in California, where there are no plant lice.
E) inserting cuttings, or slips, of the plants into California soil, where there are no plant lice.

Question 63

Which of the following conditions is necessary for successful grafting?

A) Each section must be able to form roots.
B) The grafted section must be able to form seeds.
C) Fusion of the two vascular tissues must occur.
D) Fusion of the two cambia tissues must occur.
E) Each section must be derived from the same species.

Question 64

Quaking aspen trees usually reproduce asexually in Colorado but sexually in New England. From this information, what can one hypothesize about the stability of the two environments in which the aspens grow?

A) No hypothesis can be developed from this information.
B) The Colorado aspens grow in a more stable environment.
C) The New England aspens grow in a more stable environment.
D) Both environments are stable.
E) Neither environment is stable.

Question 65

The hormone responsible for flowering in some plants is synthesized in the

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

Question 66

An apomictic seed contains an embryo that is

A) produced when two sperm fertilize one egg.
B) developed from one egg alone.
C) the result of parental self-fertilization.
D) genetically identical to its parent.
E) homozygous for most genetic traits.

Question 67

Plants that require vernalization must _______ before flowering can occur.

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

Question 68

The male gametophyte in seed plants is the _______; the mature female gametophyte is an embryo sac with _______ haploid nuclei.

Question 69

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 flowers as well. This observation supports the theory that a specific flower-initiating hormone is produced in plants. A properly controlled experiment would repeat the grafting procedure but

A) graft together the two plants and not induce the SDP.
B) omit the LDP.
C) omit the SDP.
D) shorten the SDP photoperiod.
E) include an LDP photoperiod.

Question 70

Bamboo reproduces by means of

A) rhizomes.
B) tubers.
C) corms.
D) stolons.
E) wind-dispersed seed germination.

Question 71

The process of grafting involves

A) allowing a piece of one plant (the scion) to grow onto the root of another (the stock).
B) cross-fertilization between two plants.
C) preparing several cuttings from a plant, each of which will grow into an individual plant.
D) the production of xylem and phloem from the same cambium layer.
E) the interbreeding of two species of plants.

Question 72

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

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

Question 73

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

A) light; exceeds
B) light; is less than
C) light; equals
D) dark; exceeds
E) dark; is less than

Question 74

Vegetative parts that are modified for asexual repro-duction are short, vertical stems called _______ and _______.

A) rhizomes; tubers
B) tubers; corms
C) bulbs; corms
D) bulbs; rhizomes
E) corms; rhizomes

Question 75

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) dark periods 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 76

A clone of white potatoes may be derived from underground

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

Question 77

A plant that does not require external stimuli to flower may employ which of the following mechanisms instead?

A) An internal clock
B) An unknown internal signal
C) A genetic program insensitive to the environment
D) A signal pathway dependent upon bud position
E) All of the above

Question 78

Flowering is known to be triggered by _______, although this substance has not yet been completely analyzed.

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

Question 79

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 80

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.