Chapter 30

Arrange the following structures, which can be found on male pine trees, from the largest structure to the smallest structure (or from most inclusive to least inclusive). 1. sporophyte 2. microspores 3. microsporangia 4. pollen cone 5. pollen nuclei A) 1, 4, 3, 2, 5 B) 1, 4, 2, 3, 5 C) 1, 2, 3, 5, 4 D) 4, 1, 2, 3, 5 E) 4, 3, 2, 5, 1

A) 1, 4, 3, 2, 5

Which of the following statements correctly describes a portion of the pine life cycle? A) Female gametophytes use mitosis to produce eggs. B) Seeds are produced in pollen-producing cones. C) Pollen grains contain female gametophytes. D) A pollen tube slowly digests its way through the triploid endosperm.

A) Female gametophytes use mitosis to produce eggs.

A fruit is most commonly A) a mature ovary. B) a thickened style. C) an enlarged ovule. D) a modified root. E) a mature female gametophyte

A) a mature ovary

Which of the following is not a characteristic that distinguishes gymnosperms and angiosperms from other plants? A) alternation of generations B) ovules C) integuments D) pollen E) dependent gametophytes

A) alternation of generations

Which group is noted for the independence of gametophyte and sporophyte generations from each other? A) ferns B) mosses, hornworts, and liverworts C) charophytes D) angiosperms E) gymnosperms

A) ferns

Which of the following sex and generation combinations most directly produces the pollen tube? A) male gametophyte B) female gametophyte C) male sporophyte D) female sporophyte

A) male gametophyte

Which of the following flower parts develops into a seed? A) ovule B) ovary C) fruit D) stamen

A) ovule

Within a gymnosperm megasporangium, what is the correct sequence in which the following should appear during development, assuming that fertilization occurs? 1. sporophyte embryo 2. female gametophyte 3. egg cell 4. megaspore A) 4 → 3 → 2 → 1 B) 4 → 2 → 3 → 1 C) 4 → 1 → 2 → 3 D) 1 → 4 → 3 → 2 E) 1 → 4 → 2 → 3

B) 4 → 2 → 3 → 1

Which of the following is a characteristic of all angiosperms? A) complete reliance on wind as the pollinating agent B) double internal fertilization C) free-living gametophytes D) carpels that contain microsporangia E) ovules that are not contained within ovaries

B) double internal fertilization

With respect to angiosperms, which of the following is incorrectly paired with its chromosome count? A) egg-n B) megaspore-2n C) microspore-n D) zygote-2n E) sperm-n

B) megaspore-2n

Which trait(s) is (are) shared by many modern gymnosperms and angiosperms? 1. pollen transported by wind 2. lignified xylem 3. microscopic gametophytes 4. sterile sporophylls, modified to attract pollinators 5. endosperm A) 1 only B) 1 and 3 C) 1, 2, and 3 D) 1, 3, and 5 E) 2, 4, and 5

C) 1, 2, and 3

What is true of stamens, sepals, petals, carpels, and pinecone scales? A) They are female reproductive parts. B) None are capable of photosynthesis. C) They are modified leaves. D) They are found on flowers. E) They are found on angiosperms

C) They are modified leaves.

In addition to seeds, which of the following characteristics are unique to the seed-producing plants? A) sporopollenin B) lignin present in cell walls C) pollen D) use of air currents as a dispersal agent E) megaphylls

C) pollen

In seed plants, which of the following is part of a pollen grain and has a function most like that of the seed coat? A) sporophyll B) male gametophyte C) sporopollenin D) stigma E) sporangium

C) sporopollenin

Which of the following statements is true of the pine life cycle? A) Cones are homologous to the capsules of moss plants. B) The pine tree is a gametophyte. C) Male and female gametophytes are in close proximity during gamete synthesis. D) Conifer pollen grains contain male gametophytes. E) Double fertilization is a relatively common phenomenon

D) Conifer pollen grains contain male gametophytes

All of the following cellular structures are functionally important in cells of the gametophytes of both angiosperms and gymnosperms except A) haploid nuclei. B) mitochondria. C) cell walls. D) chloroplasts. E) peroxisomes

D) chloroplasts.

Which of the following sex and generation combinations most directly produces the fruit? A) male gametophyte B) female gametophyte C) male sporophyte D) female sporophyte

D) female sporophyte

Which of the following sex and generation combinations most directly produces the integument of a pine seed? A) male gametophyte B) female gametophyte C) male sporophyte D) female sporophyte

D) female sporophyte

Which of the following sex and generation combinations most directly produces the megasporangium of pine ovules? A) male gametophyte B) female gametophyte C) male sporophyte D) female sporophyte

D) female sporophyte

Angiosperm double fertilization is so-called because it features the formation of A) two embryos from one egg and two sperm cells. B) one embryo from one egg fertilized by two sperm cells. C) two embryos from two sperm cells and two eggs. D) one embryo involving one sperm cell and an endosperm involving a second sperm cell. E) one embryo from two eggs fertilized by a single sperm cell.

D) one embryo involving one sperm cell and an endosperm involving a second sperm cell.

Gymnosperms and angiosperms have the following in common except A) seeds. B) pollen. C) vascular tissue. D) ovaries. E) ovules.

D) ovaries.

Which of the following flower parts develops into the pulp of a fleshy fruit? A) stigma B) style C) ovule D) ovary E) micropyle

D) ovary

Which of the following can be found in gymnosperms? A) nonfertile flower parts B) triploid endosperm C) fruits D) pollen E) carpels

D) pollen

Where in an angiosperm would you find a megasporangium? A) in the style of a flower B) inside the tip of a pollen tube C) enclosed in the stigma of a flower D) within an ovule contained within an ovary of a flower E) packed into pollen sacs within the anthers found on a stamen

D) within an ovule contained within an ovary of a flower

Arrange the following in the correct sequence, from earliest to most recent, in which these plant traits originated. 1. sporophyte dominance, gametophyte independence 2. sporophyte dominance, gametophyte dependence 3. gametophyte dominance, sporophyte dependence A) 1 → 2 → 3 B) 2 → 3 → 1 C) 2 → 1 → 3 D) 3 → 2 → 1 E) 3 → 1 → 2

E) 3 → 1 → 2

The seed coat's most important function is to provide A) a nonstressful environment for the megasporangium. B) the means for dispersal. C) dormancy. D) a nutrient supply for the embryo. E) desiccation resistance

E) desiccation resistance

Gymnosperms are relatively successful in terms of evolutionary longetivity, adaptations, and geographic distribution, explain why.

Gymnosperms have the five derived traits common to all seed plants (reduced gametophytes, heterospory, ovules, pollen , and seeds) making them well adapted for life on land.

It has been said that an oak is an acorn's way of making more acorns. Write an explanation that includes these terms: sporophyte, gametophyte, ovule, seed, ovary, and fruit.

In the oak's life cycle,the tree (the sporophytes) produces flowers, which contain gametophytes in pollen grains and ovules; the eggs in ovules are fertilized; the mature ovaries develop into dry fruits called acorns. We can view the oak's life cycle as starting when the acorn seeds germinate, resulting in embryos giving rise to seedling s and finally to mature trees, which produce flowers—and then more acorns.

Compare and contrast a pine cone and a flower in terms of structure and function.

Pine cones and flowers both have sporophylls, modified leaves that produce spores. Pine trees have separate pollen cones (with pollen grains) and ovulate cones (with ovules inside cone scales). In flowers, pollen grains are produced by the anthers of stamens, and ovules are within the ovaries of carpels. Unlike pine cones many flowers produce both pollen and ovules.

Describe how the parts of an ovule (integument, megaspore, megasporangium) correspond to the parts of a seed.

The integument of an ovule develops into the protective seed coat of a seed. The ovule's megaspore develops into a haploid female gametophyte: the food supply of the seed is derived from haploid gametophyte cells, and the embryo of the seed develops after the female gametophyte's egg cell is fertilized by a sperm. A remnant of the ovule's megasporangium surrounds the spore wall that encloses the seeds food supply and embryo.

Explain how the pine life cycle reflects the five adaptations common to all seed plants.

The pine life cycle illustrates heterospory, as the ovulate cones produce megaspores and pollen cones produce microspores. The reduced gametophytes are evident in the form of the microscopic pollen grains that develop from microspores and the microspoic female gametophyte that develop from the megaspore. The egg is shown developing within an ovule, and a pollen tube is shown conveying the sperm. The figure also shows the protective and nutritive features of a seed.

What features not present in seedless plants have contributed to the enormous success of seed plants on land?

The reduced gametophytes of seed plants are nurtured by sporophytes and protected from stress such as drought conditions and UV radiation. Pollen grains, with walls containing sporpollenin, provide protection during transport by wind or animals. Seeds have one or two layers of protective tissue, the seed coat that improves survival by providing more protection from environmental stresses than do the walls of spores. Seeds also contain a stored supply of food which provides nourishment for growth and after dormancy is broken and the embryo emerges as a seedling

Contrast sperm delivery in seedless plants and sperm delivery in seed plants.

To reach the eggs, the flagellated sperm of seedless plants must swim through a film of water, usually over a distance of no more than a few centimeters. In contrast, the sperm of seed plants do not require water because they are produced within pollen grains that can be transported long distances by wind or by animal pollinators. Although flagellated in some species, the sperm of seed plants do not require mobility because pollen tubes convey them from the point at which the pollen grain is deposited(near the ovules) directly to the eggs.