Deck 30: Plant Reproduction: Finding Mates and Dispersing Young

Question 1

What would be the result if dispersal took a gamete to an environment not previously colonized by that species?

A)development of a new haploid individual
B)development of a new diploid individual
C)failure to colonize the new environment
D)development of a clonal population

Answer 1

C

Question 2

Which of the following types of plants do NOT demonstrate an "alternation of generations"?

A)Chara and Choleochaete
B)bryophytes
C)lycophytes
D)gymnosperms
E)angiosperms

Answer 2

A

Question 3

Why is it significant that pollen contains a multicellular male gametophyte instead of just male gametes?

A)The non-gamete cells of the male gametophyte control the growth and development of the pollen tube.
B)The non-gamete cells of the male gametophyte provide nutrition that supports the development of the embryo.
C)The non-gamete cells of the male gametophyte undergo meiosis.
D)The non-gamete cells of the male gametophyte provide protection from desiccation and UV radiation.

Answer 3

A

Question 4

Which of the following organisms do NOT exhibit alternation of generations in their life cycles?

A)mosses
B)angiosperms
C)ferns
D)gymnosperms
E)the green algae Chara and Choleochaete

Question 5

In ferns, both the gametophyte and sporophyte are physiologically capable of surviving on their own. Which of the following are reasonable hypotheses for why vascular tissues are present only in the sporophyte generation?

A)There is no advantage for the gametophyte to grow tall, because gametes must be produced near the ground where the water needed for their free-swimming sperm is most likely to be found.
B)Vascular tissues are incompatible with desiccation tolerance.
C)Haploid organisms are incapable of developing vascular tissues, such as xylem and phloem.
D)There is no advantage for the gametophyte to grow tall, because fern gametophytes typically produce only male or female gametes at any one time.

Question 6

Which of the following groups of plants has a life cycle that includes a multicellular body composed of haploid (1n) cells?

A)Chara
B)liverworts
C)horsetails
D)ferns
E)angiosperms

Question 7

What was a major challenge that early land plants faced, and bryophytes still face, in adapting an ancestral aquatic reproductive cycle to land?

A)Successful fertilization by free-swimming sperm is rare, because it generally requires continuous water films connecting male and female gametophytes.
B)Few spores can survive dispersal in air.
C)Plants dependent on surface water may have dried out and died before completing their life cycles.
D)Gametophytes need environmental water to undergo meiosis.

Question 8

A haploid cell contains _____, and a diploid cell contains _____.

A)one set of chromosomes (1n); two sets of chromosomes (2n)
B)three sets of chromosomes (3n); two sets of chromosomes (2n)
C)two sets of chromosomes (2n); one set of chromosome (1n)
D)one set of chromosomes (1n); three sets of chromosomes (3n)

Question 9

In the life cycles of mosses and ferns, which of the following structures are diploid (2n)?

A)sporophyte
B)gametophyte
C)zygote
D)sperm
E)eggs

Question 10

Diploid (2n) cells in the _____ of mosses, ferns, gymnosperms, and angiosperms divide meiotically and form haploid (1n) spores.

Question 11

A major evolutionary constraint on the height growth of gametophytes in ferns, lycophytes, and bryophytes is thought to be imposed by:

A)the reliance of swimming sperm on environmental water.
B)a lack of genes encoding developmental pathways for a vascular system.
C)insufficient photosynthetic ability to support growth in height.
D)the dependence of the gametophyte on the sporophyte for nutrition.

Question 12

If a moss had a mutation that inhibited the production of sporopollenin, which of the following would occur?

A)The spores would dry out more quickly.
B)The moss would not be able to produce pollen.
C)Sperm would not be able to reach eggs for fertilization.
D)Spores would not be released from the sporangia.
E)The likelihood of outcrossing would decrease.

Question 13

You have discovered a plant new to science and observe what appear to be reproductive structures: On one part of the plant, you observe organ A that appears to break open under turgor pressure to release tiny cells, while on another part of the plant, organ B flings out tiny cells by a mechanism driven by cavitation. You hypothesize that organ A belongs to the gametophyte and releases:

A)egg cells, while B belongs to the sporophyte and releases sperm.
B)sperm, while B belongs to the sporophyte and releases spores.
C)spores, while B belongs to the gametophyte and releases sperm.
D)egg cells, while B belongs to the gametophyte and releases sperm.

Question 14

How did the evolution of alternation of generations aid the successful establishment of a new gametophyte generation?

A)It allowed fertilization to occur without free-swimming sperm.
B)It replaced gametophytes prone to desiccation with resistant sporophytes.
C)It produced new tissues specially adapted for aerial dispersal.
D)It amplified the number of spores produced per fertilization event.

Question 15

The male gametes (sperm) from which of the following plants require water to travel to and fertilize nearby eggs?

A)gymnosperms
B)hornworts
C)ferns
D)mosses
E)angiosperms

Question 16

In plants, _____ are defined as haploid (1n) cells that develop into gametophytes. Gametophytes, in turn, produce either haploid (1n) male or female _____ that can fuse to form diploid (2n) _____.

A)spores; gametes; zygotes
B)gametes; spores; zygotes
C)zygotes; spores; gametes
D)spores; zygotes; gametes
E)gametes; zygotes; spores

Question 17

Ferns and lycophytes differ from bryophytes in that:

A)the diploid phase of the life cycle is photosynthetically independent at maturity.
B)fertilization relies on environmental water.
C)products of meiosis are dispersed as spores.
D)the sporophyte is adapted for spore dispersal.

Question 18

Why is spore dispersal an important part of reproduction?

A)It allows for escape from pathogens and parasites.
B)It reduces competition for resources with closely related individuals.
C)It can lead to increased outcrossing and gene flow in a population.
D)It allows a single successful genotype to spread over more geographic area.

Question 19

Which has the greater degree of genetic uniformity: all the gametes produced by a single moss gametophyte or all the spores produced by a single moss sporophyte?

A)Genetic uniformity would be higher between gametes.
B)Genetic uniformity would be higher between spores.
C)Genetic uniformity would be similar between spores and gametes.
D)Both spore and gametes are sexual products and highly genetically diverse.

Question 20

In which of the following plants does the sporophyte eventually become self-sustaining (i.e., is not dependent on the gametophyte for nutrients)?

A)mosses
B)gymnosperms
C)hornworts
D)angiosperms
E)ferns

Question 21

In ferns, lycophytes, and horsetails, sporopollenin protects the _____ from drying out.

A)sporangia that are still growing
B)zygotes that are dispersing
C)haploid dispersal phase
D)diploid growth phase

Question 22

In bryophytes, the:

A)diploid gametophyte produces haploid spores by meiosis.
B)haploid gametophyte produces diploid spores by fertilization.
C)male gametes require water to reach the female gametes.
D)male gametes are dispersed by wind.
E)sporophyte produces spores by mitosis.

Question 23

Which of the following statements is TRUE of the bryophyte gametophyte generation?

A)It is diploid.
B)It produces spores.
C)It is unicellular.
D)It is photosynthetically independent.
E)It is dependent on the sporophyte.

Question 24

Which of the following statements regarding fern alternation of generations is NOT correct?

A)Ferns have a dominant, diploid sporophyte.
B)The fern gametophyte is very small, but very hardy.
C)Most fern gametophytes are capable of producing both male and female gametes.
D)Chemical signals released by gametophytes producing eggs cause other, nearby gametophytes to also produce eggs.
E)The diploid zygote will grow to become the sporophyte.

Question 25

Which of the following groups of organisms completes both its sexual reproduction and its dispersal in water?

A)Chara
B)liverworts
C)horsetails
D)ferns
E)angiosperms

Question 26

Bryophyte spores are dispersed by:

A)water.
B)air.
C)animals.
D)Bryophytes do not have spores.

Question 27

The capsule at the top of the moss sporophyte that produces spores is called the:

A)sporangium.
B)splash cup.
C)prothallus.
D)gametophyte.
E)gamete.

Question 28

Which of the following groups have a diploid stage of the life cycle that can survive exposure to the air?

A)Chara and Coleochaete
B)ferns
C)bryophytes
D)seed plants

Question 29

In vascular plants, xylem and phloem are only present in the sporophyte generation.

Question 30

Which of the following is diploid only in the single-celled zygote?

A)Chara
B)liverworts
C)horsetails
D)ferns
E)angiosperms

Question 31

Which of the following is a component of the spore-or zygote-wall (in mosses, ferns, gymnosperms, and angiosperms) and helps prevent the desiccation of these structures?

A)sporangium
B)sporopollenin
C)chitin
D)peptidoglycan
E)sporangia

Question 32

The multicellular sporophyte of bryophytes turns a single fertilization event into _____ new haploid individual(s), whereas fertilization in Chara and Coleochaete leads to _____ new haploid individual(s).

A)a single; thousands of
B)one; four
C)thousands of; four
D)four; one

Question 33

Bryophytes are the only group of land plants that produce swimming sperm.

Question 34

In ferns, relative to the sporophyte, the gametophyte stage of the life cycle is:

A)small and ephemeral.
B)large and persistent.
C)small and persistent.
D)large and ephemeral.

Question 35

In ferns, the _____ generation is physically larger.

A)haploid gametophyte
B)diploid gametophyte
C)haploid sporophyte
D)diploid sporophyte
E)haploid prothallophyte

Question 36

Which of the following statements regarding the algal sister groups of land plants is NOT correct?

A)Their dispersal phase is in the water.
B)They have diploid and haploid stages in their life cycles.
C)Fertilization requires water.
D)Their multicellular stage is haploid.
E)Their dispersal phase can be in the water or in the air.

Question 37

Which of the following groups of organisms completes sexual reproduction in water but disperses through the air?

A)Chara
B)liverworts
C)horsetails
D)ferns
E)angiosperms

Question 38

Which of the following undergoes mitosis to become multicellular in both the haploid and diploid phases of its life cycle?

A)Chara
B)liverworts
C)horsetails
D)ferns
E)angiosperms

Question 39

The complex mixture of polymers coating the spore that protects the spore from dessication and UV radiation is:

A)sporopollenin.
B)sporangium.
C)endosperm.
D)sporophyte.
E)pollen.

Question 40

Which of the following statements is TRUE about moss and fern reproduction?

A)Both mosses and ferns require wind for gamete dispersal.
B)Mosses require water for fertilization, but ferns do not.
C)Both mosses and ferns have a dominant gametophyte generation.
D)Both mosses and ferns disperse spores aerially.
E)Both mosses and ferns have a dependent sporophyte generation.

Question 41

In adaptation of plants to life on land, did spores or gametes evolve as the reproductive products for long-distance dispersal, and why?

A)Gametes: Gametes are motile and can swim long distances.
B)Gametes: A gamete can grow into a new gametophyte, establishing a new individual.
C)Spores: Spores are smaller and lighter than gametes.
D)Spores: A single spore, but not a single gamete, can establish a new individual.

Question 42

We generally think of sexual reproduction as producing offspring whose genome is related to, but not identical with, the parent plant. In which of the following does fertilization result in offspring that are genetically identical with the parent?

A)self-fertilization in ferns (sperm and egg from same gametophyte)
B)self-pollination in a pine (pollen and ovule came from the same tree)
C)self-pollination in a flowering plant (pollen and ovule came from the same flower)
D)self-pollination in a flowering plant (pollen and ovule came from different flowers on the same plant)
E)None of the answer options is correct.

Question 43

Which of the following statements is TRUE of pine trees?

A)There are two types of cones: gametophyte cones and sporophyte cones.
B)There are two types of cones: ovule cones and pollen cones.
C)Pollination is immediately followed by fertilization.
D)The spore in a pollen grain divides through meiosis to produce sperm.
E)The eggs produced in female cones become the seed.

Question 44

In which of the following structures are spores formed?

A)pollen cones
B)ovule cones
C)stamens
D)carpels
E)None of the answer options is correct.

Question 45

The pollen of seed-bearing plants and the spores of seedless vascular plants are both transported by air. How do these structures differ?

A)Spores are diploid individuals, whereas pollen grains are haploid.
B)Pollen contains a mature male gametophyte.
C)Spores are produced by the sporophyte stage of the life cycle, whereas pollen is produced by the female gametophyte stage of the life cycle.
D)Spores are unicellular, whereas pollen grains are multicellular.

Question 46

The pollen grain is the:

A)male gametophyte.
B)female gametophyte.
C)male sporophyte.
D)female sporophyte.

Question 47

One of the advantages that seeds have over spores is that they contain nutritional resources originating from photosynthesis by the maternal sporophyte that aid in establishment.

Question 48

In ferns, some leaves are "fertile" in that they bear sporangia. What are the structures in gymnosperms that are analogous to a leaf + sporangia?

A)cone scales + ovules
B)cones + seeds
C)seed coat + embryo
D)cone scale + pollen-producing sporangia

Question 49

In angiosperms, a _____ is contained in the anthers or ovaries, and the _____ consists of the rest of the plant.

A)sporophyte; bryophyte
B)gametophyte; sporophyte
C)sporophyte; gametophyte
D)bryophyte; sporophyte

Question 50

Which of the following play the same functional role (establishing new individuals by dispersal)?

A)liverwort spores and gymnosperm pollen
B)moss sperm and angiosperm pollen
C)gymnosperm pollen and angiosperm seeds
D)fern spores and gymnosperm seeds
E)lycophyte sperm and fern spores

Question 51

In comparison to large seeds, small seeds are:

A)more likely to persist in the soil.
B)more likely to exhibit some form of dormancy.
C)less likely to be produced by weedy species.
D)more likely to disperse long distances.

Question 52

Which of the following is/are a major difference(s) between all spore-dispersing and seed-dispersing plants?

A)The sporophyte of seed plants is photosynthetically independent.
B)The gametophytes of seed plants are never exposed to the external environment.
C)Seed plants disperse gametes and seeds instead of spores.
D)In seed plants, dispersed spores contain a multicellular gametophyte.

Question 53

Given what you know about pollination and fertilization in pines, what is a reasonable hypothesis for both the survival of pollen and the growth of the pollen tube inside the ovule?

A)There is a substantial transfer of signals and nutrients between male and female gametophytes.
B)The male gametophyte and pollen tube are nutritionally independent of both the female sporophyte and female gametophyte.
C)There is a substantial transfer of signals and nutrients between the male gametophyte and female sporophyte.
D)There is a substantial transfer of signals and nutrients between the male sporophyte and female sporophyte.

Question 54

In pines, complete development of the female gametophyte depends upon successful:

A)fertilization.
B)pollination.
C)both pollination and fertilization.
D)dispersal and germination of the female spore.

Question 55

Both gymnosperms and angiosperms form seeds, which can travel over long distances (either via wind or water). Which of the following are benefits of seed production and dispersal?

A)Seeds can introduce offspring into environments with ample light.
B)Seeds can introduce offspring into pathogen-free environments.
C)Seeds can introduce offspring into nutrient-rich environments.
D)Seeds can introduce offspring into environments beyond the range of spores.

Question 56

A reasonable hypothesis for the evolution in pines of a delay in complete development of the female gametophyte until after pollination is that:

A)complete development of the female gametophyte requires fusion of gametes.
B)many seeds fail to be successfully dispersed, and thus investing resources to complete the development of female gametophytes before pollination would be costly.
C)in fact, development of the female gametophyte is continuous, without any pause.
D)many ovules fail to be successfully pollinated, and thus investing resources to complete the development of female gametophytes before pollination would be costly.

Question 57

The protective outer covering of a seed is called the:

A)seed coat.
B)seed scale.
C)seed endosperm.
D)cotyledon.
E)seed sepal.

Question 58

What allows fertilization in seed plants to occur without male gametes being exposed to the external environment?

A)aerial transport of the male gametophyte
B)growth of the male gametophyte into the tissues of the ovule-bearing sporophyte
C)growth of the female gametophyte within the tissues of the ovule-bearing sporophyte
D)double fertilization

Question 59

The transport of the pollen to the ovule is called:

A)ovulation.
B)fertilization.
C)reproduction.
D)pollination.
E)germination.

Question 60

In seed plants, the outermost protective tissues of the ovule are derived from:

A)the male gametophyte.
B)the female gametophyte.
C)the sporophyte.
D)both sporophyte and gametophyte generations equally.

Question 61

Which of the following statements is true of the seeds of both gymnosperms and angiosperms?

A)Seeds from both plants contain a triploid (3n)endosperm.
B)Seeds from both plants contain a diploid (2n)embryo.
C)Seeds from both plants contain a diploid (2n)seed coat.
D)Seeds from both plants contain a haploid (1n)male gametophyte.

Question 62

The first step in the evolution of the seed plant life cycle was likely:

A)spores that could develop into either male or female gametophytes.
B)dispersal of gametophytes instead of spores.
C)the production of two types of spores in separate sporangia.
D)bisexual gametophytes.

Question 63

How do the flowers of angiosperms differ from the cones of earlier diverging seed plants?

A)Flowers have adaptations for pollen capture.
B)Flowers do not produce spores.
C)Flowers are typically bisexual, producing both male and female gametophytes.
D)Flowers allow an individual sporophyte to self-fertilize.

Question 64

Based on morphology and developmental genetics, both carpels and stamens have been interpreted as modified leaves bearing reproductive organs. From this perspective, which of the following is an accurate description of a typical angiosperm flower?

A)a leaf with sporangia that produce both male and female gametophytes
B)a shoot that produces leaves with either male or female sporangia in an alternating pattern
C)a shoot with a whorl of leaves bearing no reproductive structures, enclosing a whorl of leaves supporting sporangia from which sperm-bearing gametophytes emerge, enclosing a whorl of leaves supporting sporangia that contain egg-bearing gametophytes
D)a shoot with a whorl of leaves bearing no reproductive structures, enclosing a whorl of leaves that contain egg-bearing gametophytes, enclosing a whorl of leaves supporting sporangia from which sperm-bearing gametophytes emerge

Question 65

You are on an expedition into a tropical rainforest. You notice a tall plant with large, long, conical purple flowers that produce nectar. When you ask your guide about the plant, she pulls out a large pink fruit from her bag and explains that it is from the plant with the purple flowers. After tasting the fruit, you decide to bring the plant back home and cultivate it. You remember seeing a particular butterfly on the purple flowers during your trip to the rainforest. You decide that the pollinating butterflies are too costly and a potential danger to the ecosystem. Instead, you are going to genetically modify the plant so that it is a self-pollinating, self-compatible plant. What are some traits, both phenotypic and genotypic, that you would look for in the modified plants?

A)The plants would have a mutated S gene.
B)The anther and style would be in close proximity.
C)The plants would be shorter.
D)The plants could be pollinated by bees.

Question 66

The evolution of pollen can be thought of as the repurposing of the sporopollenin-coated wall of spores to disperse _____ by air and protect them from desiccation.

A)sperm
B)female gametes
C)male gametophytes
D)ovules

Question 67

_____ in angiosperms occurs when a sperm cell "fertilizes" a diploid (2n) cell within the future seed (eventually forming a triploid (3n) endosperm), and a second sperm fertilizes a haploid (1n) egg.

Question 68

Which of the following statements is TRUE regarding the fruits produced by angiosperms?

A)Fruits often ripen in response to ethylene.
B)Fruits are often derived from the wall of the ovary.
C)Fruits are typically derived from the seed coat.
D)Fruits ripen in response to far-red light.

Question 69

If you were to remove all the anthers from a self-incompatible plant, how would this affect the fertilization of its female gametes?

A)Fertilization would continue, because self-incompatible plants rely on pollen from other individuals.
B)Fertilization would stop, because self-incompatible plants are fertilized with pollen they produce.
C)Fertilization would continue, because self-incompatible plants are fertilized with pollen they produce.
D)Fertilization would stop, because self-incompatible plants rely on pollen from other individuals.

Question 70

In the second step in the evolution of the seed plant life cycle:

A)only the male gametophyte develops while still in the sporangia.
B)only the female gametophyte develops while still in the sporangia.
C)both gametophytes develop while still in their sporangia.
D)the male gametophyte develops from a spore that lands on the female sporangia.

Question 71

Soybeans are a self-compatible species, in which the pollen matures and is released from the anthers even before the flower opens. As a result, most ovules are fertilized by pollen from the same flower. In animals, mating between closely related individuals results in a significant loss in vigor (in-breeding depression). Why is this NOT a significant problem in plants?

A)The dominant angiosperm generation is diploid, which prevents recessive genes from being expressed.
B)Natural selection during the haploid gametophyte generation tends to eliminate recessive genes that have deleterious effects on the growth and development of the gametophyte.
C)In seed plants, the sperm does not have to swim to reach the female gamete (egg), but is instead carried there by the pollen tube.
D)Double fertilization makes it impossible for the diploid offspring to be homozygous at any loci.

Question 72

You are on an expedition into a tropical rainforest. You notice a tall plant with large, long, conical purple flowers that produce nectar. When you ask your guide about the plant, she pulls out a large pink fruit from her bag and explains that it is from the plant with the purple flowers. After tasting the fruit, you decide to bring the plant back home and cultivate it. You are successful in producing a crop of the pink fruit. You save some of the seeds to plant the following year. When the next growing season starts, you plant the seeds in the same greenhouse. To your surprise, no plants grow. What is a possible reason for this?

A)The seeds do not germinate because the flowers were not pollinated by butterflies.
B)The plants will not grow in close proximity to each other.
C)The seeds must pass through the digestive tract of a seed dispersal organism to germinate.
D)Because the plants self-pollinate, the endosperm does not develop properly, and thus the seeds do not germinate.

Question 73

In seed plants, the union of sperm and egg does not require:

A)aerial dispersal of male gametes.
B)germination of male spores on the tissues of the ovule-bearing sporophyte.
C)the release of swimming sperm into the environment.
D)the growth of the male gametophyte through the tissues of the ovule.

Question 74

Both spores and seeds are dispersed in order to establish new populations of individuals. But, compared to dispersing an individual spore, dispersing an individual seed is:

A)more costly, but has a better chance of establishing a new sporophyte.
B)less costly and has a better chance of establishing a new sporophyte.
C)about equal in terms of cost and chances of establishment.
D)less costly, but has a worse chance of establishing a new sporophyte.

Question 75

Pollen cones can be thought of as modified:

A)sporangia that produce spores, which develop only into male gametophytes.
B)leaves bearing sporangia.
C)shoots bearing leaves bearing sporangia.
D)sporophytes that produce only male spores.

Question 76

Seeds are composed of:

A)diploid tissues of the embryo.
B)haploid tissues of the gametophyte.
C)diploid tissues of the ovule-bearing sporophyte.
D)All of these choices are correct.

Question 77

An ovule can be defined as:

A)a sporangium protected by sporophyte tissue layers and containing a single non-dispersed spore that has developed into a female gametophyte.
B)the egg cell within the female gametophyte of seed plants.
C)a female gametophyte that has developed within a sporangium that has dispersed with the aid of additional protective sporophyte tissue layers.
D)the product of the union of male and female gametes within the sporangium that contains the female gametophyte, which is surrounded by additional sporophyte tissue layers.

Question 78

A truck driver is transporting a load of unripened bananas in an air-tight vehicle, and decides to stop and eat an apple after checking on his cargo. He opens the back of his truck and, while walking around the unripened bananas, he decides the apple is overripe and drops it. When the bananas are finally delivered days later, he is surprised to find that all of his bananas have ripened. Why?

A)Opening the back of the truck exposed the bananas to CO, which accelerated their ripening.
B)Exposure of the bananas to the apple (and its ethylene)instigated their ripening.
C)The bananas would naturally ripen over time, even in an air-tight environment.
D)Opening the back of the truck exposed the bananas to light of red wavelengths.

Question 79

You are studying a genus of tropical plants pollinated by lowland birds. These plants grow in low density and are widely separated from one another. However, one species in the genus has adapted to high alpine meadows, where it is the most abundant plant over large areas. The alpine species has flowers that are small and dull, and unisexual. You infer that:

A)adaptation to an alpine environment required a shift from bird to wind pollination.
B)reproduction is more efficient in the alpine environment than in the lowland environment.
C)the alpine environment is likely nutrient poor, leading to small, dull flowers and poor pollination success.
D)the alpine species is most likely bee pollinated, because bee pollination is only efficient at high densities of individual plants.

Question 80

In gymnosperms, the outer tissues of the seed that aid in dispersal and the inner tissues that serve as a store of nutrients for the embryo are:

A)both haploid.
B)both diploid.
C)haploid and diploid, respectively.
D)diploid and haploid, respectively.