Chapter 28

eudicots

"true dicots"-a monophyletic lineage that includes most of the plants once considered dicots

Plants evolved from green algae approximately _____ million years ago.

475

24. What is the function of a plant's fruit? Which group of plants has fruit? Is the nutrition found in an apple used by the tree that produced that apple? What is the purpose of making the apple (or any nutrition source)?

Seed dispersal. Seed plants that are not gymnosperms. No. For animals to eat and disperse the seeds

The evolution of lignified tissue in seedless plants allowed for which of the following?

The transportation of water from roots to above-ground tissues The ability to support upright stems

6. Howa re green algae similar to land plants. Describe 3 separate similarities.

Their chloroplast contain the photosynthetic pigments chlorophyll a and b and the accessory pigment B-carotene They have similar arrangements of the internal membrane sacs called thylakoid Their cell walls sperms and peroxisomes are similar in structure and composition. The earliest land plants even have motile sperm-a reflection of their algal ancestory their chloroplasts synthesize starch as a storage product

Having an alteration of generation life cycle means that

There are two multicellular generations, one of which produces gametes by mitosis.

25. How are herbal supplements regulated in the United States? How is this different from how medicinal drugs are regulated?

They are not. Medicinal drugs go through rigorous testing

26. Why is there a great deal of variation in the effectiveness of different herbal supplements?

They don't have to prove to be functional

angiosperms ("encased-seeds")

are a major group of seed plants

coevolution

biologist contend that the spectacular diversity of angiosperms resulted at lest in part from coevolution with animal pollinators

The living plants that are most similar to the first plants to bear gametangia are the ____

bryophytes

artificial selection

by selecting individuals with largest and most nutritious seeds, leaves or other plant parts year after year, our ancestors gradually changed the characteristics of certain wild species of plants EXAMPLE-corn. Modern corn so dramatically changed it has little resemblance to wild maize and could not survive without human intervention

9. Plants have several traits that were not found in algae. Name these adaptations.

cuticle, stomata and vascular tissue

What impact will the loss of land plants have on the soil?

decrease soil stability

Which of the following was a challenge to the survival of the first land plants?

desiccation

ecosystem services

green algea and land plants provide theses because they enhance the life supporting attributes of the atmosphere surface water, soil, and other physical components of the ecosystem

fruit

is a structure that is derived from the ovary and encloses one or more seeds

nectar

protein rich pollen or a sugar-rich fluid

flower

reproductive organ

spores

single haploid cell that divides mitotically and grows into a new organism

vascular tissue

specialized groups of cells that conduct water and nutrients from one part of the body to another

Dicots DO NOT form monophyletic group Monoocots ARE monophyletic

Dicots are paraphyletic

17. Why is a sporophyte-dominant life cycle (as seen in ferns and seed plants) advantageous?

Diploid cells can respond to varying environmental conditions more efficiently than haploid cells can-particularly if the individual is heterozygous at may genes. This idea has yet to be tested rigorously however.

lingin

complex polymer built from six-carbon rings. it is extraordinarily strong for its weight and is particularly effective in resisting compressing forces such as gravity

ecosystem

consists of all the organisms in a particular area, along with physical components of the environment such as the atmosphere, precipitation, surface water, sunlight, soil and nutrients

seed

consists of an embryo and a store of nutritive tissue, surrounded by a tough protective layer

carpel

contains a protective structure called an ovary, where the ovules are found. Meiosis occurs inside ovules, forming megaspores within megasorangia. Megaspores then divide by mitosis forming female gametophytes

most nonvascular and seedless plants are

homosporous although some club mosses and a few ferns are heterosporous

wood

in the stems and branches of some vascular plant species tracheids or a combination of tracheids and vessels form the extremely long strong support material called wood

stamen

includes a structure called an anther where mcrosporangia develop. Meisos occurs inside the microsporangia, forming microspores. Microspores then divide by mitosis to form pollen grains (male gametophytes)

homospory

is the production of a single type of spore

nonvascular plants

lack vascular tissue and lack seeds, instead reply on spores for reproduction/dispersion

Land offered plants resources

light-the amount of light reaching plant leaves on land way more plentiful=more photosynthesis carbon dioxide-the most important molecule required by photosynthetic organisms is more readily available on land--also in water CO2 diffuses into leaves alot more slowly

The evolution of the ovary was an important event in land plant diversification but not only because it protected the female gametophytes of angiosperms it also made the evolution of fruits possible

true

the evolution of flowers made efficient pollination possible, the evolution of fruits made efficient seed dispersal possible

true

zygotes and spores are both single cells that divide by mitosis to form a multicellular individual. Zygotes develop into sporophytes; spores develop into gametophytes

true

zygotes are diploid and spores and gametes are haploid

true

zygotes result from the fusion of two haploid cells such as a sperm and egg, but spores are not formed by the fusion of gametes spores are produced by meiosis inside structures called sporangia; gamets are produced by mitosis inside gametangia

true

19. What structure does the pollen grain replace? Is the pollen grain a sporophyte or gametophyte? Is the pollen grain haploid or diploid? In gymnosperms this nutritive tissue is the female gametophyte that produced the megaspores that grew into the egg. Is this nutritive tissue haploid, diploid or triploid (in gymnosperms)? What do we call the nutritive tissue in angiosperms? Is it haploid, diploid, triploid?

water dependent sperm cells. The pollen grain is a gametophyte-haploid In gymnosperms-Seeds mature as the embryo develops inside the seed, cells derived from female gametophyte become packed with nutrients provided by the sporophyte.-it is diploid In angiosperms this nutritive tissue is called endosperm. It is triploid

The diversification of angiosperms is associated with three key adaptations

water-conducting vessels flowers fruits in combination, these traits allow angiosperms to transport water,pollen and seeds efficiently

Lichens

stable associations between green algae and fungi or between cyanobacteria and fungi and are often found in terrestrial environments that lack soil such as on tree bark or bare bark

cotyledon ("seed leaf")

stores nutrition and supplies them to the developing embryonic plant

Archegonia

the egg producing gametangium-may contain sporophyte embryos

double fertilization

the involvement of two sperm nuclei

Stomata are present in all land plants except

the liverworts-have pores but no guard cells-this data suggest that land plants the earliest land plants had pores that allowed gas exchange to occur at breaks in the cuticle-covered surface. Later the evolution of guard cells gave land plants the ability to regulate gas exchange and control water loss by opening and closing their pores

Two major groups of angiosperms

the monocytledons or monocots (corn and wheat) and dictyledons or dicots (beans roses buttercups daisies oaks and maples)

heterospory

the production of two distinct types of spores by different structures

pollination

the transfer of pollen from one plant's stamen to another plants carpel

Green algae is a paraphyletic group

true

Alternation of generations-the five basic steps

1.) the sporophyte produces spores by meiosis. Spores are haploid 2.) spores germinate and divide by mitosis to develops into multicellular haploid gametophytes 3.) Gametophytes produce gametes by mitosis. Both the gametophyte and the gametes are haploid, but gametophytes are multicellular while gamets are unicellular 4.)two gametes unite during fertilization to form a diploid zygote 5.) the zygote divides by mitosis and developes into a multicellular diploid sporophyte

Although green algae are considered protists we study them along side plants because

1.) they are the closest living relatives to land plants and form a monophyletic group with them and (2) the transition from aquatic to terrestrial life occurred when land plants evolved from green algae

According to the fossil record, which groups appear first, second and third. Are plants adapted for drier conditions found early or they late arrivals in the fossil record?

According to the fossil record green algae appeared first, then nonvascular plants, seedless vascular plants, and finally the seeded plants. First evidence of land plants-cuticle spores and sporangia. Plants adapted for drier conditions were found early in the fossil records

What advantages were there to living on land instead of in the water? Were there animals preying on these first plants?

Advantages to living on land for plants were light and CO2 in abundance. No animals preying on the first plants

Species belonging to this phylum have sporophytes that depend on the gametophyte for their nutrition.

Bryophyta.

10. What function does the plant cuticle serve? What are guard cells and why are they necessary to land plant life?

Cuticle gives plants the ability to survive in dry environments because it allows them to store water (covers plants with wax) Function of guard cells= regulate the opening and closing of stomata to facilitate gas exchange and control transpiration in plants.

are an example of seedless vascular plants.

Ferns

How are plant fibers used by humans?

Fiber plants are used by humans to make clothing, rope and household articles like towels and bedding

13. Use the terms archegonia, antheridia, and gametangia in a single sentence that defines all three terms.

Gametangia are reproductive organs, the female egg producing gametangium is called an archegonium and the male sperm producing gametangium is called the antheridium

21. Give several examples of gymnosperm species.

Ginkgo, pines, redwoods

Which of the following Kingdom Plantae phyla lack both seeds and vascular tissue?

Hepaticophyta Bryophyta

18. Compare and contrast homospory and heterospory. Which plants are heterporous? Which plants are homosporous? Which group has a bisexual gametophyte?

Heterospory develops two types of spores, while homospory has one. Seed plants are heterosporous. Non-seeding are homosporous. Homosporous have bisexual gametophytes

4.How are modern maize (corn) and teosinte related?

Modern maize is a genetically modified form of teosinte-a natural and the first corn. Modern maize is much larger, has more sturdy kernels and would not survive with out human care. Teosinte is smaller, has flimsier seeds but can survive without humans

all of nonvascular plants species present today have

Low sprawling growth habit. The gametophyte is dominant and longer-lived phase of the life cycle in all of the nonvascular plants. Anchored to soil/treebar by structures called rhizoids in some mosses simple water conducting tissues are found-nonvascular plants lack vascular tissue with lingin-reinforced cell walls-have flagellated sperm that swim to eggs through water. Spores are dispersed by wind

seed plants-gymnosperms and angiosperms

MONOPHYLETIC group Angiosperms produce their seeds in ovaries Gymnosperms DO NOT Angiosperms are by far the most diverse group of plants on earth Angiosperms can be annual or perennial

Megaspores grow into ____ gametophytes. Microspores grow into ____ gametophytes.

Megaspores grow into female gametophytes Microspores develop into male gametophytes

16. How do mosses and ferns avoid self-fertilization? Which generation is dominant in mosses - sporophyte or gametophyte? Which is dominant in ferns - gametophyte or sporophyte?

Mosses and ferns do not release their sperms and eggs at the same time-in mosses the gametophyte is dominant. In ferns the sporophyte is dominant

Seedles vascular plants

Paraphyletic group Evolved after nonvascular plants all species have conducting tissues with cells that are reinforced with lingin Sporophyte dominant Gametophyte is physically independent of the sporophyte eggs retained on the gametophyte and sperm swim to egg with flagella seedless vascular plants depend on water for reproduction sporophytes develope on gametophytes and are nourished by the gametophyte when they are small

11. How do plants protect themselves from ultraviolet (uv) radiation? Why is uv radiation more of a problem on land that it is for aquatic algae?

Plants developed UV-absorbing compounds to act as a sunscreen. UV radiation is more of a land problem than water problem because water absorbs UV light

2. What ecosystem services do plants provide? Describe four.

Plants produce O2 by preforming oxygenic photosynthesis-evolved from cyanobacteria was responsible for the origin of an oxygen rich atmosphere Plants Build soil-fallen leaves decaying roots and stems provide food for worms,fungi, bacteria ect..these organisms add organic matter to the soil which changes the soil structure and ability of the soil to hold nutrients and water. Plants hold water and moderate climate-plant leaves soften the physical impact of rainfall on soil, and the bulk of plant organic matter enhances the soil's water holding capacity Plants are Primary producers-convert energy in sunlight into chemical energy. the sugars that plants produce by photosynthesis support virtually all of the other organisms present in terrestrial habitats through different levels of the food chain

3. How does plant photosynthesis affect atmospheric carbon dioxide (CO2) levels? How does it affect atmospheric oxygen levels? What is the relationship between plants, photosynthesis and fossil fuels such as coal?

Plants use CO2 and reduce it to make sugars-therefore lowering the concentration of CO2 in the atmosphere. As a byproduct of photosynthesis, plants produce 02 therefore increasing oxygen levels in the atmosphere. Fossil fuels are derived from plants that either grew during our lifetime or millions of years ago. The major deposits of fossil fuels formed when the remains of plants and animals from he Carboniferious period some 359-299 million years ago were buried and subjected to intense pressure

1. Name five basic adaptations that enabled the transition from green algae to land plants.

Prevention of water loss and drying out-stomata and cuticle Protection from UV irradiation-accumulate UV absorbing compounds called flavonoids that protected their DNA from damage Defy gravity-Grow upright-obtain vascular tissue

23. Describe how pollination syndromes can influence the shape, scent, and color of a plant's flowers. Describe how researchers determined that color influences insect pollination patterns.

Scent - Bad smell attracts carrion flies Shape - Tube-like attract hummingbirds Color - Bees like purple/yellow, hummingbirds like red Proof - observation and experimentation

5. Describe several different pharmaceuticals that are derived from land plants? What benefit do the secondary metabolites from these plants provide for the plants that make them?

Some plant derivied medicines include-opium pooppy-codein,morphine:used for pain relief cough suppressant Belladonna plant-atropine-used for dilating pupils during eye exams Foxglove-digitalin-heart medication Plants synthesize these compounds in order to repel deer, insects or other types of herbivores.

In the fern life cycle, spores are produced in _________ through the process of __________.

Sporangia, meiosis

15. are spores or gametes more genetically diverse? Why do you say this is the case?

Spores come from meiosis

8. What were the challenges to life on land (for the first land plants)?

The first land plants struggled with not drying out and dying and dealing with UV light and growing upright to obtain sunlight

7. What are the three major plant groups? Give examples of each. Are all seed plants similar?

Three main plants groups-nonvascular plants-the mosses(no seeds or vascular tissue) Seedless Vascular plants-the ferns(have vascular tissue-no seeds) Seed plants-flowering plants(seed and vascular tissue) Not all seed plants are similar some are angiosperms-they have encased seeds-while others are gymnosperms-naked seeds not encased

12. There have been tree ferns (as evidenced by the fossil record). Have there been tree-mosses? Why or why not? How do tracheids and lignin aid plants?

Tree mosses can't exist because they don't have vascular tissues. Tracheids are advanced water-conducting cells that provide structural support, and lignin makes plants rigid and woody

evolution of the flower is an elaboration of heterospory. the key innovation was the ovary each helps protect female gametophytes from insects and other predators. After pollination ovaries develop into fruits that aid in seed dispersal.

True

cuticle

a watertight barrier that coats the above ground parts of today's land plants and help them resist drying

sporopollenin

a waxy substance similar to cuticle that encases the spores and pollen from modern land plants and helps them resist drying out

endosperm

angiosperm fertilization involves two sperm cells. one sperm fuses with the egg to form the diploid 2n zygote,while the second sperm fuses with two nuclei in the female gametophyte to form a triploid 3n nutritive tissue called endosperm

gymnosperms ("naked seeds")

are another major group of seed plants

green algea

are important photosynthetic organisms in aquatic habitats particularly ;ales ponds, and other freshwater settings

vessel elements

are shorter and wider than tracheids, and their upper and lower ends have perforations where both the primary and secondary cell wall are missing

megasporangia

are sporeproducing structures that produce megaspores. Megaspores devlop into female gametophytes, which produce the large gametes called eggs by mitosis

land plants

are the key photosynthesizers in terrestrial environments.

of the algal groups which three are most similar to land plants

based on DNA sequence the most similar are-the Zygnematophyceae(conjugating algae), Coleochaetophyceae (coleochaetes) and Charophyceae(stonewarts)

Angiosperms are most closely related to

gymnosperms

In plants, which of the following are produced by meiosis?

haploid spores

What ploidy level are sperm cells in the fern lifecycle, and in which structure are they formed?

haploid, antheridium

The ___________ gametophyte stage produces gametes (eggs and sperm) by __________

haploid; mitosis

Seedless vascular plants

have vascular tissue but do not make seeds-like vascular plants they rely on spores for dispersal. Ferns are an example

tracheids

long, thin, tapering cells that have: a thickened, lingin-containing secondary cell wall in addition to a cellulose-based primary cell wall; and pits in the sides and ends of the cell where the secondary cell wall is absent where water can flow efficiently from one tracheild to the next.

stoma

most plants solve their problem of water loss with a structure called a stoma-consists of an opening surround by specialized guard cells

directed-pollination hypothesis

natural selection has favored flower scents shapes and colors that attract particular types of pollinators

adaptive radiation

occurs when a single lineage produces a large number of descendant species that are adapted to a wide variety of habitats

sepals and petals

once stamens and carpels evolved they became enclosed by modified leaves called sepals and petals

guard cells

one of two specialized crescent-shaped cells forming the border of plant stoma. guard cells can change shape to open or close the stoma

Plants synthesize toxic compounds to repel insects, deer, or other herbivores. These compounds have also become important for the development of new _____.

pharmaceuticals-Approximately 25 percent of the prescriptions written in the United States each year include at least one compound or substance derived from plants.

sporangia (sporangium)

spore producing structures

microsporangia

spore producing structures that produce microspores-microspores develop into male gametophytes which produce the small gametes called sperm by mitosis