DOCSLIB.ORG

Plants Are in Domain Eukarya Kingdom Plantae Visual Picture Of

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Plants Are in Domain Eukarya Kingdom Plantae Visual Picture Of The Diversity of Plants Plants are in Domain Eukarya • Immediate ancestors are green algae, a type of Protista, that lived in fresh water. They share: Chapter 21 Similar DNA Same photosynthetic pigments (most plants are primary producers) Store food as starch Cell walls made of cellulose Kingdom Plantae Key feature: Alternation of generations • All are eukaryotes • A diploid sporophyte produces haploid spores. The sporophyte is usually the common form of the plant. • Cell walls made of cellulose • Haploid spores divide to become haploid gametophytes. • Most are primary producers • Haploid gametophytes produce haploid gametes (eggs and Carry out photosynthesis! sperm) Chloroplasts are sites of • Egg and sperm unite to form the diploid zygote. photosynthesis • Zygote developes into the embryo. • Some are parasites Embryo relies on nutrients from parent Example: mistletoe! • Embryo develops into the sporophyte Visual picture of plant reproduction Major groups of plants 1 Bryophytes Bryophyte reproduction • Haploid gametophyte is dominant • Examples: liverworts and (green in photo) mosses Produces gametes in specialized structures (keep gametes moist!) • Most similar to ancestral • Requires water for sperm to swim to egg green algae Egg chemically attracts the sperm Egg stays in its “archegonium” • Non-vascular: lack special attached to the gametophyte Fertilization within archegonium conducting vessels for Zygote Embryo sporophyte movement of water and • Sporophyte remains attached to gametophyte (brown stalks) materials Develops and produces spores No true roots, leaves or stems • Spores disperse; develop into gametophytes Body size limited Mosses live in wetlands • Especially bogs Moss life cycle Tracheophytes: vascular plants Major groups of plants 1: Seedless vascular plants • All vascular plants have vessels reinforced with lignin Movement of materials Support • All vascular plants have dominant sporophytes • Examples of seedless vascular plants club mosses (“ground pines”) Horsetails ferns All are found in moist woodland habitats 2 Fern life cycle Ferns: sporophyte & gametophyte • Sporophyte dominant Diploid sporangia on leaf underside produce haploid spores. • Gametophyte tiny Has specialized, egg and sperm producing structures (just like bryophytes (i.e. mosses!) Eggs retained in archegonium Sperm swims to egg; fertilization within archegonium Sporophyte Gametophyte Zygote Embryo sporophyte Tracheophytes: vascular plants Major groups of plants 2: Vascular plants with seeds • Different from the seedless vascular plants Produce seeds! Contain developing embryos Contain stored food Protected by seed coat Produce pollen Pollen grains are the sperm-producing (male) gametophytes Can disperse by wind or pollinators – Fertilization no longer tied to water! Gymnosperms: non-flowering seed plants Gymnosperms: non-flowering seed plants • Examples • Conifers Ginkgos Pines, firs, spruces, hemlocks, Probably the first “modern-day” seed plants cypresses Maintained by cultivation in Asia Many are well-adapted to cold, Pollution resistant dry conditions Does Ginkgo biloba improve memory? Retain green leaves year round; Cycads can photosynthesize and grow all year Resemble large ferns Slow-growing Waterproof coating of needles Long-lived (leaves) prevents water loss – One Australia cycad is ~5000 years old! Contain an “antifreeze” in their sap Conifers (next page) that allows for nutrient transport in sub-zero temperatures 3 Conifer life cycle Conifer (gymnosperm) life cycle • Sporophyte has male and • Fertilization within female cone female cones Pollen lands on cone; pollen tube Male gametophytes (pollen) extends slowly to ovule produced in male cones Tube takes 14 months to grow, deposit sperm Pollen grains have “wings” and disperse on the wind • After fertilization, the ovule develops into the seed with Female gametophyte is Embryo within scale of female cone Nutrients Seed coat The “ovule” contains spores that divide (meiosis) to • Seed germinates become the gametophyte • Seedling mature Gametophyte produces the sporophyte eggs. Pinyon nuts Angiosperms: flowering plants • Pinyon nuts (pine nuts) • Flowers attract pollinators (mutualistic) are the seeds of pine Pollinators move pollen (and thus trees. sperm!) from flower to flower Pollinators gain food Found only in female Flower features evolved to be cones. attractive to the pollinators • Fruits (containing seeds) promote seed dispersal (How?) Edible, but you have to • Broad leaves capture sunlight beat the squirrels to effectively Some flowering plants don’t have them. broad leaves, though… (Why not?) May also have toxins to prevent being eaten Nectar - Insects Nectar - Birds Nectar - Mammals Pollinators locate flowers via: Vision (Ultraviolet) Odor 4 How do they attract Angiosperm life cycle (unique features): pollinators? Compare to others… • Food (nectar) • Pollen produced on anthers of flower • Lands on stigma • Color Via wind or pollinator Bees like yellow flowers • Builds pollen tube to ovary that contains Hummingbirds like red ovules flowers • Fertilization in ovule • After fertilization Ovule develops into the • Odor seed Flies like smelly plants Ovary develops into fruit. Trends in plant evolution Plant phylogenetic tree • Increased prominence of sporophyte; reduction of gametophyte • Development of lignin-supported vessels (support on land; larger sizes reached) • Development of alternate (non-swimming) methods for sperm to reach egg. • Development of seeds (embryo protection) • Development of flowers/fruits: pollination and seed dispersal by animals 5.
Load more

Recommended publications
  • Plant Reproduction Angiosperm Specific Adaptations Angiosperms
    4/15/2013 Gymnosperms Angiosperms Pterophytes Seeds Plant Reproduction Lycophytes Bryophytes Vascular tissue Green algae: BI 103 Plant-Animal A&P Chlorophytes Turn in Homework #1 Land plants Angiosperm specific adaptations • Unlike other plants they have: Why do plants have flowers? In – Flowers other words, what are the – Double fertilization advantages of flowering? – Fruit Discuss this question in groups Alternating Generations In more advanced plants, the sporophyte generation is Angiosperms: the Flowering plants dominant. Why do plants have flowers? Enlists partnerships with insects and other animals Less inbreeding Higher probability the pollen will reach the right plant They don’t have to produce as much pollen 1 4/15/2013 How is pollen an adaptation to land? Alternation of generations modified Allows fertilization to occur even in the absence • Pollen= Male gametophyte of available water. Contains sperm • Ovule= Female gametophyte water Contains egg Moss fertilization Pollen grains Anthers with microspores Microspore to pollen 1. The microspores divides by mitosis to produce two cells Generative cell (1n) Tube cell== vegetative nucleus (1n) 2. A two layered wall develops around the microspore to become the pollen 3. The generative cell undergoes division once more 3n total (3 nuclei) in pollen Double fertilization Fruit development 1. Two pollen nuclei enter ovule 2. One fuses with the egg to form the zygote 3. The other fuses with 2 central cell nuclei to become the endosperm (3n), food for the zygote Becomes the seed! Becomes
    [Show full text]
  • Plant Evolution an Introduction to the History of Life
    Plant Evolution An Introduction to the History of Life KARL J. NIKLAS The University of Chicago Press Chicago and London CONTENTS Preface vii Introduction 1 1 Origins and Early Events 29 2 The Invasion of Land and Air 93 3 Population Genetics, Adaptation, and Evolution 153 4 Development and Evolution 217 5 Speciation and Microevolution 271 6 Macroevolution 325 7 The Evolution of Multicellularity 377 8 Biophysics and Evolution 431 9 Ecology and Evolution 483 Glossary 537 Index 547 v Introduction The unpredictable and the predetermined unfold together to make everything the way it is. It’s how nature creates itself, on every scale, the snowflake and the snowstorm. — TOM STOPPARD, Arcadia, Act 1, Scene 4 (1993) Much has been written about evolution from the perspective of the history and biology of animals, but significantly less has been writ- ten about the evolutionary biology of plants. Zoocentricism in the biological literature is understandable to some extent because we are after all animals and not plants and because our self- interest is not entirely egotistical, since no biologist can deny the fact that animals have played significant and important roles as the actors on the stage of evolution come and go. The nearly romantic fascination with di- nosaurs and what caused their extinction is understandable, even though we should be equally fascinated with the monarchs of the Carboniferous, the tree lycopods and calamites, and with what caused their extinction (fig. 0.1). Yet, it must be understood that plants are as fascinating as animals, and that they are just as important to the study of biology in general and to understanding evolutionary theory in particular.
    [Show full text]
  • Construct a Plant Evolution Timeline
    Constructing a Timeline of Plant Evolution Use this photo as a guide to creating an interactive timeline. Refer to Geologic Time Scale charts. A good resource is http://www.ucmp.berkeley.edu/help/timeform.php Use the “Plant Timeline Cards” found at the end of this document. Attach pictures with Velcro to allow for manipulation by students, and to “build” the timeline in increments. Teachers will need to find and print photos for “seed ferns” or omit that step in the timeline. Cut and paste the text below under each picture. Cyanobacteria: Also known as blue- Mosses: These have the first identifiable green algae, these are bacteria transport systems for water (xylem), and (prokaryotes – no nucleus) that can reproduce via spores, which encase sex photosynthesize. cells to prevent desiccation. They still need to live near water. First eukaryotes (cell nucleus): Scientist think that eukaryotes evolved via Hornworts: These developed the cuticle symbiosis, with one bacteria engulfing (waxy coating to prevent water loss) and another, but not digesting it. stomata (openings in the cuticle to allow Chloroplasts were originally for gas exchange.) All land plants except cyanobacteria engulfed by another liverworts have these two features. bacterium. Development of a true vascular system Anabaena: These water organisms allowed for better transport of water evolved from being unicellular to more and provided structural support for the complex, multicellular organisms. Their plant to grow taller. specialized cells help with nitrogen fixation. Club mosses: These were the first plants to have true leaves with veins. They also Stoneworts: Scientists think that developed roots as an anchoring system colonization of land occurred only once, to allow plant to grow taller.
    [Show full text]
  • The Big Bloom—How Flowering Plants Changed the World
    The Big Bloom—How Flowering Plants Changed the World Written by Michael Klesius Republished from the pages of National Geographic magazine -- July 2002 In the summer of 1973 sunflowers appeared in my father's vegetable garden. They seemed to sprout overnight in a few rows he had lent that year to new neighbors from California. Only six years old at the time, I was at first put off by these garish plants. Such strange and vibrant flowers seemed out of place among the respectable beans, peppers, spinach, and other vegetables we had always grown. Gradually, however, the brilliance of the sunflowers won me over. Their fiery halos relieved the green monotone that by late summer ruled the garden. I marveled at birds that clung upside down to the shaggy, gold disks, wings fluttering, looting the seeds. Sunflowers defined flowers for me that summer and changed my view of the world. Flowers have a way of doing that. They began changing the way the world looked almost as soon as they appeared on Earth about 130 million years ago, during the Cretaceous period. That's relatively recent in geologic time: If all Earth's history were compressed into an hour, flowering plants would exist for only the last 90 seconds. But once they took firm root about 100 million years ago, they swiftly diversified in an explosion of varieties that established most of the flowering plant families of the modern world. Today flowering plant species outnumber by twenty to one those of ferns and cone-bearing trees, or conifers, which had thrived for 200 million years before the first bloom appeared.
    [Show full text]
  • Plant Reproduction | Topic Notes
    Plant Reproduction | Topic Notes Sexual reproduction is the fusion of male and female gametes to produce a diploid zygote. (The new individual is genetically different from both parents). Advantages include genetic variation, reduced competition (between parent & offspring) and good chance of surviving harsh winter. A disadvantage is that there’s a long period of growth required. Structure of flowering plant: Megaspore (egg) formation & microspore (pollen) formation: The carpel (female part of the flower) is composed of the stigma (sticky to trap pollen grains), style (supports stigma in best position to trap pollen grains) and ovary (contains 1 or more ovules which following fertilisation will develop into seeds). The stamen (male part of the flower) is composed of the anther (produces pollen grains) and filament (supports anther in best position to transport pollen grains). Sepals support the developing flower before it blooms. Petals may be bright coloured in insect pollinated plants (to attract them). The receptacle is the organ from which the flower develops and functions in supporting it. Pollination is the transfer of pollen from the anther to the stigma of a flower of the same species. It may be: 1. Self-pollination: the transfer of pollen from the anther to the stigma in the same plant. 2. Cross-pollination: the transfer of pollen from the anther to the stigma of a different plant but of the same species. 1 Plant Reproduction | Topic Notes Fertilisation is the union of a haploid male gamete with a haploid female gamete, to produce a diploid zygote. Once a pollen grain has landed on the stigma, the tube nucleus moves down through the stigma and style forming a pollen tube and enters the ovule at the micropyle, guided towards the egg by chemotropism, the tube nucleus then degenerates.
    [Show full text]
  • Plant Diversity Unique Plant Adaptations Alternation Of
    8/9/2010 Land plants Origins Shared ancestor with green algae. Plant Diversity Researchers have identified green algae called charophyceans as the closest The Evolution of the relatives of land plants Photosynthetic Terrestrial Plants Unique Plant Adaptations First true land plants were short Adaptations for a terrestrial existence and required water for reproduction 1) Roots --anchoranchor the plant and absorb water & nutrients from the soil. 2) Cuticle ––aa waxy coating to prevent drying out 3) Stomata ––porespores in the leaves and stems that allow for gas exchange. 4) Conducting vessels ––forfor transport of water , minerals, and sugars through the plant body. 5) Lignin --StiffeningStiffening and support of stems. 6) Unique reproductive structures e.g. pollen –– for transporting gametes. Alternating Generations Alternation of Generations In more advanced plants sporophyte generation dominant. The alternating life cycle of plants that involves changes between a: 1)Sporophyte generation AND………. 2) G ametophyte generation 1 8/9/2010 Mosses & nonvascular plants have life Contrasting the Generations cycles dominated by gametophytes Hairy-cap moss Sporophyte Gametophyte Diploid state (double set Haploid state (half the Brown Capsule of chromosomes in cells –– amount of chromosomes full set) in cells) Sporophyte Produces seeds in seed Produces the gametes bearing plants i.e. (sperm & egg). Makes spores Predominant form in Gametophyte Predominant form in mosses & ferns (lower higher plants e.g. trees. plants). (Green & leafy) Characteristics of Mosses Life Cycle of Mosses Division Bryophytes The sporophyte forms on, and is nourished by, the dominant gametophyte Nonvascular (don’t have special methods of conducting water & minerals) ––tendtend to be very small.
    [Show full text]
  • Lesson 6: Plant Reproduction
    LESSON 6: PLANT REPRODUCTION LEVEL ONE Like every living thing on earth, plants need to make more of themselves. Biological structures wear out over time and need to be replaced with new ones. We’ve already looked at how non-vascular plants reproduce (mosses and liverworts) so now it’s time to look at vascular plants. If you look back at the chart on page 17, you will see that vascular plants are divided into two main categories: plants that produce seeds and plants that don’t produce seeds. The vascular plants that do not make seeds are basically the ferns. There are a few other smaller categories such as “horse tails” and club mosses, but if you just remember the ferns, that’s fine. So let’s take a look at how ferns make more ferns. The leaves of ferns are called fronds, and brand new leaves that have not yet totally uncoiled are called fiddleheads because they look like the scroll-shaped end of a violin. Technically, the entire frond is a leaf. What looks like a stem is actually the fern’s equivalent of a petiole. (Botanists call it a stipe.) The stem of a fern plant runs under the ground and is called a rhizome. Ferns also have roots, like all other vascular plants. The roots grow out from the bottom of the rhizome. Ferns produce spores, just like mosses do. At certain times of the year, the backside of some fern fronds will be covered with little dots called sori. Sori is the plural form, meaning more than one of them.
    [Show full text]
  • Attractant, Acting As a Homing Device for the Swimming Sperm. Sperm
    r 62 CHAPTER 3 EVOLUTION AND DIVERSITY OF GREEN AND LAND PLANTS UN[T 11 EVOLUTION AND DIVERSITY OF PLANTS 63 gemmae propagules 2 rows of 1 row of sperm cells dorsal leaves ventral leaves (sterile “jacket” layer) neck sperm cells “ ‘fl gemmae cup I / pore dorsal (upper) ventral (lower) A B view view thalloid liverwort leafy liverwort FIGURE 3.10 A. Antheridia. B. Archegonia. Both are apomorphies of land plants. 4 (,, ••1• attractant, acting as a homing device for the swimming sperm. of the liverworts, mosses, and hornworts is relatively small, Sperm cells enter the neck of the archegonium and fertilize ephemeral, and attached to and nutritionally dependent upon the egg cell to form a diploid (2n) zygote. In addition to the gametophyte (see later discussion). effecting fertilization, the archegonium serves as a site for The relationships of the liverworts, mosses, and hornworts embryo/sporophyte development and the establishment of a to one another and to the vascular plants remain unclear. nutritional dependence of the sporophyte upon gametophytic Many different relationships among the three lineages have archegonium tissue. been proposed, one recent of which is seen in Figure 3.6. (n) The land plants share other possible apomorphies: the presence of various ultrastructural modifications of the sperm LIVERWORTS cells, fiavonoid chemical compounds, and a proliferation of Liverworts, also traditionally called the Hepaticae, are one of archegoniophore (n) archegoniophore (n) (longitudinal-section) heat shock proteins. These are not discussed here. the monophyletic groups that are descendents of some of the (longitudinal-section) first land plants. Today, liverworts are relatively minor com ponents of the land plant flora, growing mostly in moist, fertilization DIVERSITY OF NONVASCULAR LAND PLANTS shaded areas (although some are adapted to periodically dry, hot habitats).
    [Show full text]
  • Pteridophytes
    PTERIDOPHYTES Prep Smart. Stay Safe. PTERIDOPHYTES Habitat : Found in cool, damp, shady places though some may flourish well in sandy-soil conditions. Main plant body : Sporophyte which is differentiated into true root, stem and leaves . PTERIDOPHYTES Vascular cryptogams (Xylem and Phloem) Seedless , non flowering plants PTERIDOPHYTES The leaves :small (microphylls) -Selaginella large (macrophylls) -Ferns. Selaginella PTERIDOPHYTES Fern leaves are cpmmonly called as Fronds, they first appear tightly coiled at tip , later on they unroll. They form a pattern of growth called as Circinate Vernation , early leaves grow faster on their lower surface than the upper surface. PTERIDOPHYTES The sporophytes bear sporangia that are subtended by leaf-like appendages called sporophylls. PTERIDOPHYTES In some cases sporophylls may form distinct compact structures called strobili or cones (Selaginella, Equisetum). The sporangia produce spores by meiosis in spore mother cells. Equisetum PTERIDOPHYTES The spores germinate to give rise to inconspicuous, small but multicellular, free-living, mostly photosynthetic thalloid gametophytes called prothallus PTERIDOPHYTES These gametophytes require cool, damp, shady places to grow. Because of this specific restricted requirement and the need for water for fertilisation, the spread of living pteridophytes is limited and restricted to narrow geographical regions. PTERIDOPHYTES The gametophytes bear male and female sex organs called antheridia and archegonia, respectively. PTERIDOPHYTES Water is required for transfer of antherozoids– the male gametes released from the antheridia, to the mouth of archegonium , Zooidogamy Fusion of male gamete with the egg present in the archegonium result in the formation of zygote. PTERIDOPHYTES Zygote thereafter produces a multicellular well-differentiated sporophyte which is the dominant phase of the pteridophytes.
    [Show full text]
  • Evolution of Land Plants P
    Chapter 4. The evolutionary classification of land plants The evolutionary classification of land plants Land plants evolved from a group of green algae, possibly as early as 500–600 million years ago. Their closest living relatives in the algal realm are a group of freshwater algae known as stoneworts or Charophyta. According to the fossil record, the charophytes' growth form has changed little since the divergence of lineages, so we know that early land plants evolved from a branched, filamentous alga dwelling in shallow fresh water, perhaps at the edge of seasonally-desiccating pools. The biggest challenge that early land plants had to face ca. 500 million years ago was surviving in dry, non-submerged environments. Algae extract nutrients and light from the water that surrounds them. Those few algae that anchor themselves to the bottom of the waterbody do so to prevent being carried away by currents, but do not extract resources from the underlying substrate. Nutrients such as nitrogen and phosphorus, together with CO2 and sunlight, are all taken by the algae from the surrounding waters. Land plants, in contrast, must extract nutrients from the ground and capture CO2 and sunlight from the atmosphere. The first terrestrial plants were very similar to modern mosses and liverworts, in a group called Bryophytes (from Greek bryos=moss, and phyton=plants; hence “moss-like plants”). They possessed little root-like hairs called rhizoids, which collected nutrients from the ground. Like their algal ancestors, they could not withstand prolonged desiccation and restricted their life cycle to shaded, damp habitats, or, in some cases, evolved the ability to completely dry-out, putting their metabolism on hold and reviving when more water arrived, as in the modern “resurrection plants” (Selaginella).
    [Show full text]
  • The Ferns and Their Relatives (Lycophytes)
    N M D R maidenhair fern Adiantum pedatum sensitive fern Onoclea sensibilis N D N N D D Christmas fern Polystichum acrostichoides bracken fern Pteridium aquilinum N D P P rattlesnake fern (top) Botrychium virginianum ebony spleenwort Asplenium platyneuron walking fern Asplenium rhizophyllum bronze grapefern (bottom) B. dissectum v. obliquum N N D D N N N R D D broad beech fern Phegopteris hexagonoptera royal fern Osmunda regalis N D N D common woodsia Woodsia obtusa scouring rush Equisetum hyemale adder’s tongue fern Ophioglossum vulgatum P P P P N D M R spinulose wood fern (left & inset) Dryopteris carthusiana marginal shield fern (right & inset) Dryopteris marginalis narrow-leaved glade fern Diplazium pycnocarpon M R N N D D purple cliff brake Pellaea atropurpurea shining fir moss Huperzia lucidula cinnamon fern Osmunda cinnamomea M R N M D R Appalachian filmy fern Trichomanes boschianum rock polypody Polypodium virginianum T N J D eastern marsh fern Thelypteris palustris silvery glade fern Deparia acrostichoides southern running pine Diphasiastrum digitatum T N J D T T black-footed quillwort Isoëtes melanopoda J Mexican mosquito fern Azolla mexicana J M R N N P P D D northern lady fern Athyrium felix-femina slender lip fern Cheilanthes feei net-veined chain fern Woodwardia areolata meadow spike moss Selaginella apoda water clover Marsilea quadrifolia Polypodiaceae Polypodium virginanum Dryopteris carthusiana he ferns and their relatives (lycophytes) living today give us a is tree shows a current concept of the Dryopteridaceae Dryopteris marginalis is poster made possible by: { Polystichum acrostichoides T evolutionary relationships among Onocleaceae Onoclea sensibilis glimpse of what the earth’s vegetation looked like hundreds of Blechnaceae Woodwardia areolata Illinois fern ( green ) and lycophyte Thelypteridaceae Phegopteris hexagonoptera millions of years ago when they were the dominant plants.
    [Show full text]
  • Gene Genealogies and Population Variation in Plants
    Colloquium Gene genealogies and population variation in plants Barbara A. Schaal* and Kenneth M. Olsen Department of Biology, Washington University, St. Louis, MO 63130 Early in the development of plant evolutionary biology, genetic selection. Morphology, karyotypes, and fitness components are drift, fluctuations in population size, and isolation were identified central traits for understanding evolution and adaptation, but as critical processes that affect the course of evolution in plant they limit which evolutionary processes can be studied. In his species. Attempts to assess these processes in natural populations book, Stebbins discusses such events as fluctuations in popula- became possible only with the development of neutral genetic tion size, random fixation (genetic drift), and isolation as all markers in the 1960s. More recently, the application of historically affecting the process of evolution (see passage quoted above; ref. ordered neutral molecular variation (within the conceptual frame- 1). However, the study of these mechanisms requires markers work of coalescent theory) has allowed a reevaluation of these that are not under selection. microevolutionary processes. Gene genealogies trace the evolu- In the years after the publication of Stebbins’ book, among tionary relationships among haplotypes (alleles) with populations. the first major technical advances in evolutionary biology were Processes such as selection, fluctuation in population size, and the development of protein electrophoresis and the identifi- population substructuring affect the geographical and genealog- cation of allozyme variation in natural populations. Many ical relationships among these alleles. Therefore, examination of allozymes are selectively neutral, and thus, for the first time, these genealogical data can provide insights into the evolutionary evolutionary biologists could attempt to assess the amount of history of a species.
    [Show full text]