MB-Chapter 30-Seed Plants

In terms of alternation of generations, the internal parts of the pollen grains of seed-producing plants are most similar to a In terms of alternation of generations, the internal parts of the pollen grains of seed-producing plants are most similar to a 1. fern gametophyte bearing only antheridia. 2. fern sporophyte. 3. hermaphroditic fern gametophyte. 4. moss gametophyte bearing both male and female gametangia. 5. moss sporophyte.

1. fern gametophyte bearing only antheridia.

In the pine, microsporangia form _____ microspores by _____. 1. haploid ... meiosis 2. diploid ... meiosis 3. diploid ... mitosis 4. triploid ... fertilization 5. haploid ... mitosis

1. haploid ... meiosis Diploid microsporangia form haploid microspores by meiosis.

In pines, an embryo is a(n) _____. 1. immature sporophyte 2. seed 3. food reserve for the immature sporophyte 4. immature female gametophyte 5. immature male gametophyte

1. immature sporophyte The diploid embryo will develop into a seedling and then into a mature pine tree.

n angiosperms, which number in Figure 30.1 most nearly represents the event that initiates the formation of endosperm?

10

Which of the following statements correctly describes a portion of the pine life cycle? 1. Seeds are produced in pollen-producing cones. 2. Female gametophytes use mitosis to produce eggs. 3. A pollen tube slowly digests its way through the triploid endosperm. 4. Pollen grains contain female gametophytes.

2. Female gametophytes use mitosis to produce eggs.

In addition to seeds, which of the following characteristics is unique to the seed-producing plants? In addition to seeds, which of the following characteristics is unique to the seed-producing plants? 1.lignin present in cell walls 2. pollen 3. megaphylls 4. use of air currents as a dispersal agent 5. sporopollenin

2. pollen

Which of these statements is true about the gametophyte tissue that surrounds the pine embryo? 1. It is the remnant of the pollen tube. 2. It develops from the fusion of a microspore and a megaspore. 3. It functions as a haploid food reserve. 4. It functions as a triploid food reserve. 5. It functions as a diploid food reserve.

3. It functions as a haploid food reserve. This gametophyte tissue is a source of nourishment for the embryo.

Of the four haploid cells produced by a pine cone's megasporocyte (megaspore mother cell), _____ survive(s). 1. three 2. two 3. one 4. integuments 5. four

3. one

The seed coat's most important function is to provide The seed coat's most important function is to provide 1. dormancy. 2. the means for dispersal. 3. protection for the embryo. 4. a nonstressful environment for the megasporangium. 5. a nutrient supply for the embryo.

3. protection for the embryo.

The Brazil nut tree, Bertholletia excels (n = 17), is native to tropical rain forests of South America. It is a hardwood tree that can grow to over 50 meters tall, is a source of high-quality lumber, and is a favorite nesting site for harpy eagles. As the rainy season ends, tough-walled fruits, each containing 8-25 seeds (Brazil nuts), fall to the forest floor. Brazil nuts are composed primarily of endosperm. About $50 million worth of nuts are harvested each year. Scientists have discovered that the pale yellow flowers of Brazil nut trees cannot fertilize themselves and admit only female orchid bees as pollinators. The agouti (Dasyprocta spp.), a cat-sized rodent, is the only animal with teeth strong enough to crack the hard wall of Brazil nut fruits. It typically eats some of the seeds, buries others, and leaves still others inside the fruit, which moisture can now enter. The uneaten seeds may subsequently germinate. If a female orchid bee has just left a Brazil nut tree with nectar in her stomach, and if she visits another flower on a different Brazil nut tree, what is the sequence in which the following events should occur? 1. double fertilization 2. pollen tube emerges from pollen grain 3. pollen tube enters micropyle 4. pollination 2, 4, 1, 3 4, 2, 1, 3 2, 4, 3, 1 4, 2, 3, 1 4, 3, 2, 1

4, 2, 3, 1

All seed plants _____. 1. are nonvascular 2. produce antheridia and archegonia on the same gametophyte 3. exhibit a dominant gametophyte generation 4. are heterosporous 5. produce flower

4. are heterosporous All seed plants produce separate male and female spores.

Generally, wind pollination is most likely to be found in seed plants that grow 1. in relative isolation from other members of the same species. 2. along coastlines where prevailing winds blow from the land out to sea. 3. in well-drained soils. 4. in dense, single-species stands. 5. close to the ground.

4. in dense, single-species stands.

Harold and Kumar are pre-med and pre-pharmacy students, respectively. They complain to their biology professor that they should not have to study about plants because plants have little relevance to their chosen professions. Which adaptation(s) of land plants is (are) likely to provide Harold with future patients? 1. those for using wind to disperse male gametophytes 2. defenses against herbivory 3. sporophyte dominance 4. All three of the responses above are potentially medically significant. 5. Two of the responses above are potentially medically significant.

5. Two of the responses above are potentially medically significant.

Which of the following is a characteristic of all angiosperms? 1. ovules that are not contained within ovaries 2. free-living gametophytes 3. complete reliance on wind as the pollinating agent 4. carpels that contain microsporangia 5. double internal fertilization

5. double internal fertilization

Harold and Kumar are pre-med and pre-pharmacy students, respectively. They complain to their biology professor that they should not have to study about plants because plants have little relevance to their chosen professions. Kumar, especially, might be well advised to learn more about: 1. accessory photosynthetic pigments. 2. cell wall components, such as lignins and pectins. 3. sporopollenin. 4. the wax of cuticles. 5. plant secondary compounds.

5. plant secondary compounds.

The major difference between angiosperms and gymnosperms comes from the _____. 1. dominance or lack of dominance of the sporophyte generation 2. presence or absence of vascular structures 3. production of microspores versus megaspores 4. presence or absence of alternation of generations 5. presence or absence of a protective covering over the ovule

5. presence or absence of a protective covering over the ovule Angiosperms have a protective covering over the ovule. Gymnosperms do not. All the other traits listed are shared by both groups.

The embryo sac of an angiosperm flower is best represented by which number in the figure?

7

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

In a typical angiosperm, what is the sequence of structures encountered by the tip of a growing pollen tube on its way to the egg? 1. micropyle 2. style 3. ovary 4. stigma A) 4 → 2 → 3 → 1 B) 4 → 3 → 2 → 1 C) 1 → 4 → 2 → 3 D) 1 → 3 → 4 → 2 E) 3 → 2 → 4 → 1

A) 4 → 2 → 3 → 1

Harold and Kumar are pre-med and pre-pharmacy students, respectively. They complain to their biology professor that they should not have to study about plants because plants have little relevance to their chosen professions. From reading their biology textbook, what would Harold and Kumar discover? A) About one-quarter of all prescription drugs come from seed plants. B) Prescription drugs that enter the water table are responsible for the extinction of many plants. C) Much of what was once rain forest has been replanted with fields of medicinally valuable plants. D) All rain forest plants contain at least one chemical useful as a medicine.

A) About one-quarter of all prescription drugs come from seed plants.

Which of the following is true concerning flowering plants? A) The flower includes sporophyte tissue. B) The gametophyte generation is dominant. C) The gametophyte generation is what we see when looking at a large plant. D) The sporophyte generation is not photosynthetic. E) The sporophyte generation consists of relatively few cells within the flower.

A) The flower includes sporophyte tissue.

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

The Brazil nut tree, Bertholletia excels (n = 17), is native to tropical rain forests of South America. It is a hardwood tree that can grow to over 50 meters, is a source of high-quality lumber, and is a favorite nesting site for harpy eagles. As the rainy season ends, tough-walled fruits, each containing 825 seeds (Brazil nuts), fall to the forest floor. About $50 million worth of nuts are harvested each year. Scientists have discovered that the pale yellow, self-incompatible flowers of Brazil nut trees admit only female orchid bees as pollinators. Orchid bees are to Brazil nut trees as ________ are to pine trees. A) breezes B) rain droplets C) seed-eating birds D) squirrels E) both seed-eating birds and squirrels

A) breezes

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

A) male gametophyte

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

A) ovule

In onions (Allium), cells of the sporophyte have 16 chromosomes within each nucleus. Match the number of chromosomes present in each of the following onion tissues. How many chromosomes should be in a generative cell nucleus? A) 4 B) 8 C) 16 D) 24 E) 32

B) 8

In onions (Allium), cells of the sporophyte have 16 chromosomes within each nucleus. Match the number of chromosomes present in each of the following onion tissues. How many chromosomes should be in a tube cell nucleus? A) 4 B) 8 C) 16 D) 24 E) 32

B) 8

In onions (Allium), cells of the sporophyte have 16 chromosomes within each nucleus. Match the number of chromosomes present in each of the following onion tissues. How many chromosomes should be in an embryo sac nucleus? A) 4 B) 8 C) 16 D) 24 E) 32

B) 8

Over human history, which process has been most important in improving the features of plants that have long been used by humans as staple foods? A) genetic engineering B) artificial selection C) natural selection D) sexual selection E) pesticide and herbicide application

B) artificial selection

How have fruits contributed to the success of angiosperms? A) by nourishing the plants that make them B) by facilitating dispersal of seeds C) by attracting insects to the pollen inside D) by producing sperm and eggs inside a protective coat E) by producing triploid cells via double fertilization

B) by facilitating dispersal of seeds

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

The generative cell of male angiosperm gametophytes is haploid. This cell divides to produce two haploid sperm cells. What type of cell division does the generative cell undergo to produce these sperm cells? A) binary fission B) mitosis C) meiosis D) mitosis without subsequent cytokinesis E) meiosis without subsequent cytokinesis

B) mitosis

Which of the following are structures of angiosperm gametophytes? A) immature ovules B) pollen tubes C) ovaries D) stamens E) sepals

B) pollen tubes

In onions (Allium), cells of the sporophyte have 16 chromosomes within each nucleus. Match the number of chromosomes present in each of the following onion tissues. How many chromosomes should be in an embryo nucleus? A) 4 B) 8 C) 16 D) 24 E) 32

C) 16

Angiosperms are the most successful terrestrial plants. Which of the following features is unique to them and helps account for their success? A) wind pollination B) dominant gametophytes C) fruits enclosing seeds D) embryos enclosed within seed coats E) sperm cells without flagella Answer: C

C) fruits enclosing seeds

Which structure is common to both gymnosperms and angiosperms? A) stigma B) carpel C) ovule D) ovary E) anthers

C) ovule

Among plants known as legumes (beans, peas, alfalfa, clover, etc.) the seeds are contained in a fruit that is itself called a legume, better known as a pod. Upon opening such pods, it is commonly observed that some ovules have become mature seeds, whereas other ovules have not. Thus, which of the following statements is (are) true? 1. The flowers that gave rise to such pods were not pollinated. 2. Pollen tubes did not enter all of the ovules in such pods. 3. There was apparently not enough endosperm to distribute to all of the ovules in such pods. 4. The ovules that failed to develop into seeds were derived from sterile floral parts. 5. Fruit can develop, even if all ovules within have not been fertilized. A) 1 only B) 1 and 5 C) 2 and 4 D) 2 and 5 E) 3 and 5

D) 2 and 5

In onions (Allium), cells of the sporophyte have 16 chromosomes within each nucleus. Match the number of chromosomes present in each of the following onion tissues. How many chromosomes should be in an endosperm nucleus? A) 4 B) 8 C) 16 D) 24 E) 32

D) 24

Which of the following is a true statement about angiosperm carpels? A) Carpels are features of the gametophyte generation. B) Carpels consist of anther and stamen. C) Carpels are structures that directly produce male gametes. D) Carpels surround and nourish the female gametophyte. E) Carpels consist of highly modified microsporangia.

D) Carpels surround and nourish the female gametophyte.

Hypothetically, one of the major benefits of double fertilization in angiosperms is to A) decrease the potential for mutation by insulating the embryo with other cells. B) increase the number of fertilization events and offspring produced. C) promote diversity in flower shape and color. D) coordinate developmental timing between the embryo and its food stores. E) emphasize embryonic survival by increasing embryo size.

D) coordinate developmental timing between the embryo and its food stores.

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

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 these is a male gametophyte?

E Pollen grains are male gametophytes. A pollen cone contains hundreds of microsporangia in small reproductive leaves called sporophylls. Cells in the microsporangia undergo meiosis to form haploid microspores. The microspores then develop into pollen grains with tiny wings; these are the male gametophytes.

Arrange the following structures from largest to smallest, assuming that they belong to two generations of the same angiosperm. 1. ovary 2. ovule 3. egg 4. carpel 5. embryo sac A) 4, 2, 1, 5, 3 B) 4, 5, 2, 1, 3 C) 5, 4, 3, 1, 2 D) 5, 1, 4, 2, 3 E) 4, 1, 2, 5, 3

E) 4, 1, 2, 5, 3

What is the greatest threat to plant diversity? A) insects B) grazing and browsing by animals C) pathogenic fungi D) competition with other plants E) human population growth

E) human population growth

Reptilian embryos are protected from desiccation by a leathery shell. Similarly, which pair of structures protects seed plants' embryos and male gametophytes, respectively, from desiccation? A) ovules-waxy cuticle B) ovaries-filaments C) fruits-stamens D) pollen grains-waxy cuticle E) integuments-sporopollenin

E) integuments-sporopollenin

A botanist discovers a new species of land plant with a dominant sporophyte, chlorophylls a and b, and cell walls made of cellulose. In assigning this plant to a phylum, which of the following, if present, would be least useful? A) endosperm B) seeds C) sperm that lack flagella D) flowers E) spores

E) spores

Gymnosperms were most abundant during the _____. Mesozoic Precambrian Carboniferous Paleozoic Cenozoic

Mesozoic Gymnosperms were the dominant plants of the Mesozoic.

Select the correct statement describing the life cycle of angiosperms. a) Double fertilization in the life cycle of seed plants results in the production of a diploid zygote and a triploid endosperm nucleus. b) In angiosperm life cycles, the female gametophyte is the ovule. c) The life cycle of seed plants does not include a gametophyte generation

a) Double fertilization in the life cycle of seed plants results in the production of a diploid zygote and a triploid endosperm nucleus.

What are the products of meiosis in the life cycle of a seed plant? a) Megaspores or microspores b) Sperm or eggs c) Male or female gametophytes

a) Megaspores or microspores Review the life cycles of a pine tree and an angiosperm, respectively. In both life cycles, meiosis produces microspores (which develop into male gametophytes within pollen grains) or a megaspore (which develops into a female gametophyte or embryo sac within an ovule).

In angiosperms, pollination is the transfer of pollen grain to the _____ of a flower on the same plant or another plant of the same species. a) stigma b) ovary c) style d) ovulate cone e) anther

a) stigma

A carpel is composed of _____. a) stigma, style, and ovary b) ovary, ovule, and anther c) petal, sepal, and stamen d) ovule, megasporocyte, and anther e) zygote, anther, and endosperm

a) stigma, style, and ovary

In pines, the female gametophyte contains _____, each of which contains a(n) _____. archegonia ... sperm cell archegonia ... egg microsporangia ... egg cell antheridia ... egg antheridia ... sperm cell

archegonia ... egg In pines, a megaspore repeatedly grows and divides, giving rise to a female gametophyte. The female gametophyte is the site in which egg-bearing gametophytes develop.

In which of the following pairs do the structures play comparable roles in the plant and animal life cycles? a) A plant seed and a bird egg b) A plant sporophyte and an adult animal c) The male gametophyte of a plant and the testes of an animal

b) A plant sporophyte and an adult animal A plant sporophyte and an adult animal are both diploid organisms. Read about the life cycle of an angiosperm.

Which of these is unique to flowering plants? a) haploid gametophytes b) double fertilization c) pollen production d) a dominant sporophyte generation e) an embryo surrounded by nutritive tissue

b) double fertilization In flowering plants one sperm nucleus fertilizes the egg and the other sperm nucleus fuses with two other nuclei found within the ovule, thus forming triploid endosperm.

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

In flowering plants the integuments of the ovule develop into a(n) _____. a) cotyledon b) sporophyte c) seed coat d) endosperm e) fruit

c) seed coat

A stamen consists of _____. a) ovary and sepal b) stigma and style c) stigma and anther d) anther and filament e) stigma and filament

d) anther and filament

When you look at a pine or maple tree, the plant you see is a _____. diploid sporophyte haploid gametophyte haploid sporophyte triploid endosperm diploid gametophyte

diploid sporophyte The sporophyte generation is the dominant generation of vascular plants.

Human survival literally depends on the produce of _____. a) gymnosperms b) gnetophytes c) cycads d) ginkgoes e) angiosperms

e) angiosperms Angiosperms are the source of our major food crops, including rice, wheat, maize, and barley. They also provide cotton and linen, and medicines such as digitalis and codeine. Rubber, coffee, chocolate, and aromatic oils come from flowering plants. Woods such as oak, cherry, and walnut are derived from angiosperms.

The male gametophytes of flowering plants are also referred to as _____. a) male sporophytes b) embryo sacs c) endosperm d) megaspores e) pollen grains

e) pollen grains

In gymnosperms megaspores develop into _____ . female gametophytes ovulate cones pollen grains female sporophytes male gametophytes

female gametophytes Even though the gametophyte stage of alternation of generations is minimized in gymnosperms and angiosperms, spores still give rise to gametophytes.

Angiosperms are different from all other plants because only they have _____. 1. a life cycle that involves alternation of generations 2. seeds 3. a sporophyte phase 4. flowers 5. a vascular system

flowers

In pine trees, pollen grains get to the ovule via the _____. eggs megaspore pollen cone integument micropyle

micropyle Pollen grains gain entry into the ovule via the micropyle.

Ovules are found within structure _____.

ovaries (B)

Unlike most angiosperms, grasses are pollinated by wind. As a consequence, some unnecessary parts of grass flowers have almost disappeared. Which of the following parts would you expect to be most reduced in a grass flower? petals carpels anthers stamens ovaries

petals

Which of the following can be found in gymnosperms? nonfertile flower parts carpels pollen triploid endosperm fruits

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? male gametophyte sporopollenin stigma sporophyll sporangium

sporopollenin