Deck 40: Plant Reproduction

Question 1

Pollen from a plant with the S₁S₂ genotype is recognized and allowed to germinate on the stigma of the same plant with the S₁S₂ genotype.According to the S-system hypothesis,this indicates that the plant is

A)self-compatible and can self-pollinate.
B)self-compatible and must cross-pollinate.
C)self-incompatible and can self-pollinate.
D)self-incompatible and must cross-pollinate.

Answer 1

A

Question 2

Cottonwood,aspen,and willow trees have drab-colored flowers with no petals that appear before the tree's leaves are out in the spring;they are dioecious.What does that indicate about these trees?

A)Their insect pollinators are probably color blind.
B)Early spring birds are probably the pollinators.
C)Their pollen is dispersed by wind.
D)Flower color or shape is not related to pollinators.

Answer 2

C

Question 3

Plants in crop fields such as corn are genetically very similar.What are benefits of this phenomenon? What are pitfalls of that phenomenon?

Answer 3

Benefits-Harvest is synchronized;consistent,dependable crops.Pitfalls-Entire crop is genetically susceptible to diseases,insects,and weather problems.

Question 4

What is an essential part of alternation of generations in plants?

A)meiosis to produce gametes
B)meiosis to produce zygotes
C)mitosis to produce gametes
D)fertilization to produce spores
E)fertilization to produce gametes

Question 5

If an ovary contains 50 ovules,what is the minimum number of pollen grains that must land in order to form 50 mature seeds?

A)25
B)50
C)100
D)It is impossible to tell.

Question 6

A summer occupation in the Corn Belt states is de-tasseling the corn: removing unwanted male flowers so that female flowers on the same plant are pollinated by the desired pollen for the hybrid corn.What does this tell you about corn?

A)The flowers are perfect and the plant is dioecious.
B)The flowers are perfect and the plant is monoecious.
C)The flowers are imperfect and the plant is dioecious.
D)The flowers are imperfect and the plant is monoecious.

Question 7

A population of flowers varies from deep blue to nearly white.Bees are active during the day and prefer color.Moths are active at night,when colors are not very visible and white is more conspicuous.Design a scenario in which the blue and white flowers form two species where there once was one species.You must end with a conclusion that the two new species cannot interbreed (a definition of a species).

Question 8

What is not true about the carpel of a flower?

A)The stigma receives the pollen.
B)The style provides the pathway for the growth of the pollen tube.
C)Meiosis of the megaspore forms the eight nuclei of the embryo sac.
D)The ovary encloses one or more ovules,which contain the embryo sac.

Question 9

The flowering hormone is made in ________ and alters development of ________.

A)flowers;leaves
B)flowers;root meristem
C)leaves;apical meristem
D)leaves;flowers
E)roots;flowers

Question 10

A gardener in Canada wants to surprise his mother on her birthday and make her favorite Shrubalthea bush flower in May instead of the end of June.The bush is growing in the greenhouse.Which of the following might make the Shrubalthea bush flower early?

A)fertilizing the bush
B)grafting leaves of a Shrubalthea that was exposed to long nights
C)grafting leaves of a Shrubalthea that was exposed to short nights
D)exposing flower buds of the Shrubalthea bush to long nights
E)exposing flower buds of the Shrubalthea bush to short nights

Question 11

It is estimated that animal- or insect-pollinated plants produce 1000 pollen grains for each ovule;wind-pollinated plants produce 1,000,000 pollen grains for each ovule.What does that indicate about pollination systems?

A)Wind-pollinated plants rarely produce seeds.
B)Wind pollination is more efficient than animal-assisted pollination.
C)Wind pollination is less efficient than animal-assisted pollination.
D)Wind pollination is costlier to the plant than animal-assisted pollination.

Question 12

The sperm and egg each contribute 50% of the nuclear genetic material to the zygote that becomes the embryo and the new plant.Mitochondria and plastids that become chloroplasts are passed primarily from the female parent.What feature of the male or female gametophytes accounts for this?

A)The female gametophyte is small and mobile and can pack a lot of cytoplasm into a tiny space.
B)The female gametophyte is larger and formed from one surviving megaspore.
C)The male gametophyte is formed in the anthers.
D)Meiosis is not involved in the formation of the female gametophyte.

Question 13

During self-fertilization,which of the following is absent?

A)pollination
B)transfer of pollen from one plant to the other
C)transfer of pollen from anther to stigma
D)formation of gametes
E)all of the above

Question 14

What is the male gametophyte made of?

A)polar nuclei and embryo sac
B)polar nuclei and tube cell
C)generative cell and two gametes
D)generative cell and tube cell
E)microspores

Question 15

Most plants are adept at asexual reproduction.What is the probable explanation for the energy spent for sexual reproduction?

A)Photosynthesis produces so much sugar and oxygen,they need to be used.
B)Sexual reproduction ensures that the same genes will be passed on to offspring.
C)Sexual reproduction mixes up genes,contributing to variation in a species.
D)Sexual reproduction is a sign of good health of the organism.

Question 16

Which of the following correctly identifies the function of the flower part named?

A)Sepals protect the flower bud.
B)Petals attract seed-dispersing animals.
C)The stigma produces pollen.
D)The carpel attracts pollinators.
E)All of these answers are correct.

Question 17

What is the similarity between spores and gametes?

A)They are produced by meiosis.
B)They are haploid.
C)They divide by mitosis.
D)They can fuse with another cell to form a new organism.
E)They are made by a sporophyte.

Question 18

While looking at a flower in your garden,you notice that it has carpels with very long styles and stamens with very short filaments.This plant is most likely to reproduce by

A)cross-pollination.
B)selfing.
C)asexually.

Question 19

How are the life cycles of liverworts and angiosperms alike?

A)In both groups,the sporophyte is the dominant generation.
B)In both groups,the gametophyte is the dominant generation.
C)In both groups,the gametophyte is smaller than the sporophyte.
D)In both groups,the sporophyte is smaller than the gametophyte.
E)In both groups,the sporophyte produces spores.

Question 20

Home flower gardeners in northern latitudes like to grow plants that flower only in the spring or flower only in the late summer and fall.They are planting flowers that are most sensitive to

A)their summer vacation schedule.
B)night length.
C)temperature differences.
D)the watering schedule.
E)fertilizer applications.

Question 21

After double fertilization in angiosperms,what development sequence is correct?

A)The embryo in the seed develops into endosperm.
B)The ovary wall becomes the fruit.
C)The ovule becomes the fruit.
D)The entire carpel dries up and falls off the plant.

Question 22

If a hypocotyl does not elongate during seed germination and early seedling growth,where will the cotyledons be?

A)aboveground and above the seed
B)aboveground and below the seed
C)in the ground with the seed coat

Question 23

Unripe fruits protect seeds from predation and early germination.What is the major function of ripe fruits?

A)attracting pollinators
B)dispersing seed
C)deterring predators
D)keeping the seed hydrated before germination

Question 24

Endosperm is a major part of monocot seeds.In most dicots,

A)the same thing is true;there is a substantial amount of endosperm.
B)endosperm never even starts to form after double fertilization.
C)endosperm nutrients are repackaged into the cotyledons.
D)endosperm replaces cotyledons in the seed.

Question 25

Mosses and ferns tend to be most abundant in warm,moist climates.Why do mosses and ferns have problems with reproduction in deserts?

A)Their pollen is not resistant to desiccation.
B)Their seeds are not resistant to desiccation.
C)Their sperm must swim for fertilization to occur.
D)Their ovules must swim for fertilization to occur.

Question 26

Charles Darwin experimented with reactions of grass seedlings (monocots)relative to applied auxin (a plant hormone)and light.He used the youngest seedlings with a structure that dicots do not have.What is the name of that structure?

A)coleoptile
B)cotyledons
C)radicle
D)seed coat

Question 27

Hammer orchids resemble female thyranide wasps and release a chemical signal called pheromone to deceive male thyranide wasps and accomplish pollination.Compared to food-deceiving orchids,is it more or less likely that pollen of the hammer orchid will be transferred to the flower of the same species than to the flower of a different species?

A)more likely
B)less likely
C)similar probability

Question 28

Suppose that 100 pollen grains land on a stigma,and 50 mature seeds are formed in the fruit.What does this indicate about the pollination process and success?

A)50% success: 100 pollen grains grew to 50 ovules,and double fertilization occurred
B)50% success: evidently,only 50 sperm pollinated 50 anthers
C)50% success: 50 sperm fertilized 50 eggs,and 50 sperm fused with 50 polar nuclei
D)50% success: 50 sperm fertilized 50 eggs,and 50 sperm fused with 100 polar nuclei

Question 29

Gardeners purchase packets of seeds that are put in the ground and germinate.Native plant seeds usually need a scarification treatment or a real or simulated winter (stratification),some seeds need light,and others need a smoke treatment.What do these adaptations to the environmental conditions reveal about where the plants grow?

Question 30

Before plowing a field,a farmer thought the bare field looked weed-free.Three days after plowing and turning over the soil,he was amazed to see thousands of tiny seedlings.What kinds of seeds did the plowing help with germination?

A)large seeds that need winter in order to germinate
B)small seeds that need light in order to germinate
C)seeds that need exhaust from the tractor in order to germinate
D)large seeds that need less water in order to germinate

Question 31

Which of these events occurs first in seed germination?

A)Cell division occurs in the embryo,and growth starts.
B)Mitochondria multiply and provide energy for growth processes.
C)Water is taken up.
D)Oxygen is produced and proteins are synthesized.
E)New mRNAs and proteins are produced.

Question 32

A researcher found a beautiful plant while traveling in Alaska and collected its seeds.When she came back to Florida,she soaked some seeds in pure water and some in water with hormone gibberellin.When she put seeds to grow in soil,only seeds soaked with gibberellin germinated.The seeds that were soaked in pure water did not germinate because of the

A)presence of pericarp.
B)low concentration of ABA.
C)absence of nutrients in pure water.
D)Any of the above might have reduced germination rate.

Question 33

Which of these events happens first in nearly all seed germination?

A)The cotyledons appear aboveground,turn green,and photosynthesize.
B)The radicle emerges from the seed to obtain water and nutrients from the soil.
C)The hypocotyl elongates to lift cotyledons aboveground.
D)The cotyledons disappear as their stored nutrition is used.

Question 34

It is possible to make seedless tomatoes by removing the anthers of the flower and putting a hormone (auxin)on the stigma of the tomato flower.Weekly applications are required.Over the course of development,the stigma and style fall off,and the ovary develops into a normal-looking tomato with no seeds.Normally,seed and fruit formation are coordinated using hormone signaling.What does the application of auxin indicate?

A)The stigma of a tomato flower produces auxin that is necessary for pollination.
B)Pollen is not usually required to make fruits.
C)Applied auxin must substitute for an auxin source in a developing seed.
D)All of the above answers apply.

Question 35

To conclude that the Clark's nutcracker is a mutualistic seed disperser,not just a predator,you would need to determine that

A)if the birds are not present,whitebark pine cannot spread.
B)the birds eat all the seeds they cache.
C)seeds in the caches can germinate to produce seedlings.
D)bears and squirrels do not eat any of the seeds.

Question 36

The egg of a plant has a haploid chromosome number of 12 (n = 12).What is true about the number of chromosomes in the cells of other tissues of this plant?

A)The sperm has 6 chromosomes.
B)The leaves and stems have 12 chromosomes.
C)The zygote has 12 chromosomes.
D)The endosperm has 36 chromosomes.
E)All of these answers apply.

Question 37

You find a fruit that has little hooks around the outside of the pericarp.You can assume that ________ is/are the pollinator.

A)wind
B)birds
C)mammals
D)cannot answer based on the information given

Question 38

Angiosperms are unique in having double fertilization that forms endosperm.What is true about double fertilization in angiosperms?

A)Two sperm combine with a polar nucleus to form endosperm.
B)Two sperm combine with two eggs to form the zygote and endosperm.
C)One sperm combines with the polar nuclei to form the zygote,and one sperm combines with the egg to form endosperm.
D)One sperm combines with the egg to form the zygote,and one sperm combines with the polar nuclei to form endosperm.

Question 39

Which of these is not a step in the formation of an embryo from a zygote in the seed?

A)The root and shoot systems emerge from the seed.
B)Basal cells form a connection between the parent plant and the developing embryo.
C)Mitosis produces a mass of cells that become the young embryo.
D)Cells differentiate to form the basic plant tissue types.
E)The early root-shoot axis is formed.

Question 40

Whitebark pine frequently grows in clumps of 3-4.That growth pattern indicates

A)one seed can branch repeatedly to form several seedlings.
B)more than one seed germinates,and sibling seedlings are produced in one cache.
C)bears and squirrels move seeds into one cache.

Question 41

Pines,including the whitebark pine,are pioneer-type trees,meaning the young seedlings and trees need to grow in open areas with sunlight.Which of these would be most helpful in spreading the seeds of the trees?

A)bears,which eat and digest the seeds
B)squirrels,which bury the seeds in the shade of the pines
C)rodents,which cache the seeds in their deep underground burrows
D)Clark's nutcracker,which caches the seeds on sunny hillsides