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PowerPoint Lectures for
Biology: Concepts & Connections, Sixth Edition
Campbell, Reece, Taylor, Simon, and Dickey
Chapter 17
Lecture by Joan Sharp
Plants, Fungi, and the
Colonization of Land
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Introduction: Plants and Fungi—A Beneficial Partnership
Plants and fungi colonized land together
Mycorrhizae, mutually beneficial associations of plant roots and fungi hyphae, enabled plants to colonize land
– Mycorrhizal fungi absorb water, phosphorus, and other minerals from soil and make them available to the plant
– The sugars produced by the plant nourish the fungus
PLANT EVOLUTION AND DIVERSITY
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500 million years ago, the algal ancestors of plants formed a green carpet on the edge of lakes and coastal salt marshes
Green algae called charophytes are the closest living relatives of plants
17.1 Plants have adaptations for life on land
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17.1 Plants have adaptations for life on land
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Land plants are a clade, defined by a set of derived characters
– Alternation of haploid and diploid generations
– Walled spores produced in sporangia
– Male and female gametangia
– Multicellular, dependent sporophyte embryos
17.1 Plants have adaptations for life on land
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Life on land offered new opportunities
– Unlimited sunlight
– Abundant CO2
– Initially, few pathogens or herbivores
17.1 Plants have adaptations for life on land
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Challenges of terrestrial life
– Maintaining moisture within cells
– Obtaining resources from soil and air
– Supporting body in air
– Reproducing and dispersing offspring without water
Spores
Flagellatedsperm
Stem Leaf
Seed
Pollen
Leaf
FernStomata; roots anchor plants,absorb water; lignified cellwalls; vascular tissue;fertilization requires moisture
Roots
Stem
Roots
Pine treeStomata; roots anchor plants, absorb water; lignified cell walls; vascular tissue;fertilization does not require moisture
MossStomata only on sporophytes; primitive roots anchor plants,no lignin; no vascular tissue;fertilization requires moisture
Spores
Flagellatedsperm
Leaf
Stem
Roots
Flagellatedsperm
Vasculartissue
Key
Holdfast(anchors alga)
AlgaWater supportsalga. Whole algaperforms photo-synthesis;absorbs water,CO2, andminerals fromwater.
Flagellatedsperm
Stem
Leaf
FernStomata; roots anchor plants,absorb water; lignified cellwalls; vascular tissue;fertilization requires moisture
Roots
MossStomata only on sporophytes; primitive roots anchor plants,no lignin; no vascular tissue;fertilization requires moisture
Spores
Flagellatedsperm
Leaf
Stem
Roots
Flagellatedsperm
Vasculartissue
Key
Holdfast(anchors alga)
AlgaWater supportsalga. Whole algaperforms photo-synthesis;absorbs water,CO2, andminerals fromwater.
Spores
Leaf
Seed
Pollen
Stem
Roots
Pine treeStomata; roots anchor plants, absorb water; lignified cell walls; vascular tissue;fertilization does not require moisture
Vasculartissue
Key
17.1 Plants have adaptations for life on land
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In all plants, the zygote develops into an embryo while attached to and nourished by the parent plant
Plants are embryophytes, with multicellular, dependent embryos
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17.2 Plant diversity reflects the evolutionary history of the plant kingdom
Four key adaptations for life on land distinguish the main lineages of the plant kingdom
– Dependent embryos (characteristic of all plants)
– Lignified vascular tissues
– Seeds
– Flowers
Ancestralgreenalga
Origin of land plants(about 475 mya)
1
Origin of vascular plants(about 425 mya)
2
Origin of seed plants(about 360 mya)
3
Mosses
Lycophytes (club mosses,spike mosses, quillworts)
Pterophytes (ferns,horsetails, whisk ferns)
Gymnosperms
Angiosperms
Millions of years ago (mya)
500 450 350 300400 0
Liverworts
Hornworts
ALTERNATION OF GENERATIONS
AND PLANT LIFE CYCLES
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The haploid gametophyte produces gametes (eggs and sperm) by mitosis
Fertilization results in a diploid zygote
The zygote develops into the diploid sporophyte, which produces haploid spores by meiosis
Spores grow into gametophytes
17.3 Haploid and diploid generations alternate in plant life cycles
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Haploid (n)
Diploid (2n)
Key Gametophyteplant (n)
Gametes (n)
Sperm
Egg
Mitosis
Haploid (n)
Diploid (2n)
Key Gametophyteplant (n)
Gametes (n)
Sperm
Egg
Fertilization
Zygote (2n)
Mitosis
Haploid (n)
Diploid (2n)
Key Gametophyteplant (n)
Gametes (n)
Sperm
Egg
Fertilization
Zygote (2n)
Sporophyteplant (2n)
Mitosis
Mitosis
Haploid (n)
Diploid (2n)
Key Gametophyteplant (n)
Gametes (n)
Sperm
Egg
Fertilization
Zygote (2n)
Sporophyteplant (2n)
Meiosis
Spores (n)
Mitosis
Mitosis
Haploid (n)
Diploid (2n)
Key Gametophyteplant (n)
Gametes (n)
Sperm
Egg
Fertilization
Zygote (2n)
Sporophyteplant (2n)
Meiosis
Spores (n)
Mitosis
Mitosis
Mitosis
Gametophytes make up a bed of moss
– They produce eggs and flagellated sperm in gametangia
– Sperm swim through water to the egg
The zygote develops within the gametangium into a mature sporophyte, which remains attached to the gametophyte
– Meiosis occurs in sporangia at the tips of the sporophyte stalk
– Haploid spores are released from the sporangium and develop into gametophytes
17.4 Mosses have a dominant gametophyte
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17.4 Mosses have a dominant gametophyte
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Animation: Moss Life Cycle
MaleHaploid (n)
Diploid (2n)
KeyGametophytes (n)
Female
Sperm (n)
Egg (n)
Fertilization
Femalegametangium
1
1
MaleHaploid (n)
Diploid (2n)
KeyGametophytes (n)
Female
Sperm (n)
Egg (n)
Fertilization
Femalegametangium
1
1
2
Zygote (2n)
MaleHaploid (n)
Diploid (2n)
KeyGametophytes (n)
Female
Sperm (n)
Egg (n)
Fertilization
Femalegametangium
1
1
2
Zygote (2n)Sporophyte (2n)
3 Mitosis
and development
Sporangium
Stalk
MaleHaploid (n)
Diploid (2n)
KeyGametophytes (n)
Female
Sperm (n)
Egg (n)
Fertilization
Femalegametangium
1
1
2
Zygote (2n)Sporophyte (2n)
3 Mitosis
and development
Sporangium
Stalk
4
Meiosis
Spores (n)
MaleHaploid (n)
Diploid (2n)
KeyGametophytes (n)
Female
Sperm (n)
Egg (n)
Fertilization
Femalegametangium
1
1
2
Zygote (2n)Sporophyte (2n)
3 Mitosis
and development
Sporangium
Stalk
4
Meiosis
Spores (n)
5 Mitosis and
development
17.5 Ferns, like most plants, have a dominant sporophyte
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Fern gametophytes are small and inconspicuous
– They produce flagellated sperm that swim to the egg and fertilize it to produce a zygote
– The zygote initially develops within the female gametangia but eventually develops into an independent sporophyte
Sporangia develop on the underside of the leaves of the sporophyte
– Within the sporangia, cells undergo meiosis to produce haploid spores
– Spores are released and develop into gametophytes
17.5 Ferns, like most plants, have a dominant sporophyte
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Animation: Fern Life Cycle
Haploid (n)
Diploid (2n)
Key
Gametophyte (n)
Sperm (n)
Egg (n)
Fertilization
1
Female
gametangium (n)
Haploid (n)
Diploid (2n)
Key
Gametophyte (n)
Sperm (n)
Egg (n)
Fertilization
1
2
Zygote (2n)
Female
gametangium (n)
Haploid (n)
Diploid (2n)
Key
Gametophyte (n)
Sperm (n)
Egg (n)
Fertilization
Female
gametangium (n)
1
2
Zygote (2n)New sporophyte (2n)
Mitosis and
development
3
4
Mature sporophyte
Clusters of
sporangia
Haploid (n)
Diploid (2n)
Key
Gametophyte (n)
Sperm (n)
Egg (n)
Fertilization
Female
gametangium (n)
1
2
Zygote (2n)New sporophyte (2n)
Mitosis and
development
Meiosis
3
4
Mature sporophyte
Clusters of
sporangia
Mitosis and
development
5
Spores (n)
17.6 Seedless plants dominated vast “coal forests”
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Seedless plants formed vast ancient forests in low-lying wetlands during the Carboniferous period (360–299 million years ago)
– When they died, the plants formed peat deposits that eventually formed coal
Coal, oil, and natural gas are fossil fuels
– Oil and natural gas formed from marine organisms; coal formed from seedless plants
– Burning fossil fuels releases CO2, causing climate warming
17.7 A pine tree is a sporophyte with gametophytes in its cones
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A pine cone holds all of the tree’s reproductive stages: spores, eggs, sperm, zygotes, and embryos
– Each scale of the cone contains sporangia that produce spores by meiosis
– The spores produce gametophytes within the cone
The male gametophyte is a pollen grain, released from pollen cones and carried by wind to female cones
Female ovulate cones carry two ovules on each stiff scale
– Each ovule contains a sporangium surrounded by the integument
Animation: Pine Life Cycle
Sporangia producespores; spores developinto pollen grains.
Spore mother cell (2n)
Meiosis
1
Sporangium (2n)
Scale
Integument
Pollination
Ovule
Meiosis
2
3Pollen grains(male gameto-phytes) (n)
Ovulate conebears ovules.
Haploid (n)
Diploid (2n)
Key
Mature sporophyte
Sporangia producespores; spores developinto pollen grains.
Spore mother cell (2n)
Meiosis
1
Sporangium (2n)
Scale
Integument
Pollination
Ovule
Meiosis
2
3Pollen grains(male gameto-phytes) (n)
Ovulate conebears ovules.
Haploid (n)
Diploid (2n)
Key
Mature sporophyte
Egg (n)
Fertilization
Femalegametophyte (n)
Male gametophyte (pollen grain)
Sperm (n)
A haploid spore celldevelops into femalegametophyte, whichmakes eggs.
4
Pollen growstube to eggand makesand releasessperm.
5
Sporangia producespores; spores developinto pollen grains.
Spore mother cell (2n)
Meiosis
1
Sporangium (2n)
Scale
Integument
Pollination
Ovule
Meiosis
2
3Pollen grains(male gameto-phytes) (n)
Ovulate conebears ovules.
Haploid (n)
Diploid (2n)
Key
Mature sporophyte
Egg (n)
Fertilization
Femalegametophyte (n)
Male gametophyte (pollen grain)
Sperm (n)
A haploid spore celldevelops into femalegametophyte, whichmakes eggs.
4
Pollen growstube to eggand makesand releasessperm.
5
Seed coat
Zygote(2n)
Zygote developsinto embryo, andovule becomes seed.
6
Food supply
Embryo (2n)Seed
Sporangia producespores; spores developinto pollen grains.
Spore mother cell (2n)
Meiosis
1
Sporangium (2n)
Scale
Integument
Pollination
Ovule
Meiosis
2
3Pollen grains(male gameto-phytes) (n)
Ovulate conebears ovules.
Haploid (n)
Diploid (2n)
Key
Mature sporophyte
Egg (n)
Fertilization
Femalegametophyte (n)
Male gametophyte (pollen grain)
Sperm (n)
A haploid spore celldevelops into femalegametophyte, whichmakes eggs.
4
Pollen growstube to eggand makesand releasessperm.
5
Seed coat
Zygote(2n)
Zygote developsinto embryo, andovule becomes seed.
6
Food supply
Embryo (2n)Seed
7 Seed germinates,and embryo grows into seedling.
17.7 A pine tree is a sporophyte with gametophytes in its cones
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In pollination, a pollen grain lands on a scale in an ovulate cone and enters an ovule
– The scales then grow together, sealing up the cone
– Within the sealed cone, the gametophytes produce gametes
Fertilization occurs a year after pollination, when a sperm moves down a pollen tube to the egg to form a zygote
– The zygote develops into a sporophyte embryo, and the ovule becomes a seed, with stored food and a protective seed coat
The seed is a key adaptation for life on land and a major factor in the success of seed plants
17.8 The flower is the centerpiece of angiosperm reproduction
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Flowers contain separate male and female sporangia and gametophytes
Flowers usually consist of sepals, petals, stamens (which produce pollen), and carpels (which produce eggs)
– Sepals enclose the flower before it opens
– Petals attract animal pollinators
Stamens include a filament and anther, a sac at the top of each filament that contains male sporangia and releases pollen
17.8 The flower is the centerpiece of angiosperm reproduction
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Video: Flower Blooming (time lapse)
Stamen
Anther
Filament
Petal
Receptacle
Ovule
Sepal
Stigma
Style
Ovary
Carpel
17.8 The flower is the centerpiece of angiosperm reproduction
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The carpel is the female reproductive structure, including the ovary
– The ovary encloses the ovules, which contain sporangia that will produce a female gametophyte
Ovules develop into seeds; ovaries mature into fruit
17.9 The angiosperm plant is a sporophyte with gametophytes in its flowers
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The angiosperm life cycle
1. Meiosis in the anthers produces haploid spores that form the male gametophyte (pollen grains)
2. Meiosis in the ovule produces a haploid spore that forms a tiny female gametophyte, including the egg
3. A pollen tube from the pollen grain to the ovule carries a sperm that fertilizes the egg to form a zygote
4. Each ovule develops into a seed, consisting of an embryo (a new sporophyte) with a food supply and a seed coat
5. The ovary wall forms a fruit
17.9 The angiosperm plant is a sporophyte with gametophytes in its flowers
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Animation: Plant Fertilization
Video: Flowering Plant Life Cycle (time lapse)
Animation: Seed Development
Meiosis
1
Egg (n)
Haploid spores in anthers develop intopollen grains: male gametophytes.
Meiosis
Pollen grains (n)
Ovule
Haploid (n)
Diploid (2n)
Key
2 Haploid spore in each ovuledevelops into female gameto-phyte, which produces an egg.
Meiosis
1
Haploid (n)
Diploid (2n)
Key
Egg (n)
Sperm
Haploid spores in anthers develop intopollen grains: male gametophytes.
2
Meiosis
Pollen grains (n)
Ovule
Haploid spore in each ovuledevelops into female gameto-phyte, which produces an egg.
3 Pollination andgrowth of pollen tube
Stigma
Pollen grain
Pollen tube
Fertilization
Meiosis
1
Haploid (n)
Diploid (2n)
Key
Egg (n)
Fertilization
Sperm
Zygote(2n)
Haploid spores in anthers develop intopollen grains: male gametophytes.
2
Meiosis
Pollen grains (n)
Ovule
Haploid spore in each ovuledevelops into female gameto-phyte, which produces an egg.
3 Pollination andgrowth of pollen tube
Stigma
Pollen grain
Pollen tube
4
Meiosis
1
Haploid (n)
Diploid (2n)
Key
Egg (n)
Fertilization
Sperm
Seed coat
Zygote(2n)
Food supply
Embryo (2n)
Seeds
Haploid spores in anthers develop intopollen grains: male gametophytes.
2
Meiosis
Pollen grains (n)
Ovule
Haploid spore in each ovuledevelops into female gameto-phyte, which produces an egg.
3 Pollination andgrowth of pollen tube
Stigma
Pollen grain
Pollen tube
4
Fruit(matureovary)
6
Seed5
Meiosis
1
Haploid (n)
Diploid (2n)
Key
Egg (n)
Fertilization
Sperm
Seed coat
Zygote(2n)
Food supply
Embryo (2n)
Seeds
Haploid spores in anthers develop intopollen grains: male gametophytes.
2
Meiosis
Pollen grains (n)
Ovule
Haploid spore in each ovuledevelops into female gameto-phyte, which produces an egg.
3 Pollination andgrowth of pollen tube
Stigma
Pollen grain
Pollen tube
4
Fruit(matureovary)
6
Seed5
Ovary
Ovule
Stigma
Anther
Sporophyte (2n)
Seed germinates,and embryogrows intoplant.
7
17.10 The structure of a fruit reflects its function in seed dispersal
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Fruits, ripened ovaries of flowers, are adaptations that disperse seeds
– Some rely on wind for seed dispersal
– Some hitch a ride on animals
– Fleshy, edible fruits attract animals
Animation: Fruit Development
17.11 CONNECTION: Angiosperms sustain us—and add spice to our diets
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Most human food is provided by the fruits and seeds of angiosperms
– Corn, rice, wheat, and other grains are dry fruits
– Apples, cherries, tomatoes, and squash are fleshy fruits
– Spices such as nutmeg, cinnamon, cumin, cloves, ginger, and licorice are also angiosperm fruits
17.12 EVOLUTION CONNECTION: Pollination by animals has influenced angiosperm evolution
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90% of angiosperms use animals to transfer pollen
– Birds are attracted by colorful flowers, but not scent
– Beetles are attracted by fruity odors, but not color
– Bats are attracted by large, highly scented flowers
– Wind-pollinated flowers produce large amounts of pollen
17.13 CONNECTION: Plant diversity is an irreplaceable resource
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More than 50,000 square miles of forest are cleared every year
– Replanted areas have greatly reduced biological diversity
Loss of forests has greatly reduced diversity of life on Earth
– The loss of plant diversity removes potentially beneficial medicines
– More than 25% of prescription drugs are extracted from plants
FUNGI
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17.14 Fungi absorb food after digesting it outside their bodies
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Fungi are absorptive heterotrophic eukaryotes that digest their food externally and absorb the nutrients
Most fungi consist of a mass of threadlike hyphaemaking up a mycelium
– Hyphal cells are separated by cross-walls with pores large enough for ribosomes, mitochondria, and nuclei to cross
– Some are multinucleate without cross-walls
– Hyphae have a huge surface area to secrete digestive enzymes and absorb food
Fungal hyphae are surrounded by a cell wall with chitin
Animation: Fungal Reproduction and Nutrition
Hypha
Mycelium
17.15 Fungi produce spores in both asexual and sexual life cycles
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Many fungal species can reproduce both sexually and asexually
Fungi produce huge numbers of asexual spores, each of which can germinate to form a new fungus
In many fungi, sexual fusion of haploid hyphae leads to a heterokaryotic stage, in which cells contain two genetically distinct haploid nuclei
– Hours or centuries may pass before parental nuclei fuse to form a short-lived diploid phase
– Zygotes undergo meiosis inside specialized reproductive structures and disperse haploid spores
17.15 Fungi produce spores in both asexual and sexual life cycles
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Video: Allomyces Zoospore Release
Video: Phlyctochytrium Zoospore Release
Fusion of cytoplasm
Heterokaryoticstage
Spore-producingstructures
Asexualreproduction
Spores(n)
Diploid (2n)
Haploid (n)
Heterokaryotic (n + n)(unfused nuclei)
Key
Sexualreproduction
Zygote(2n)
Fusion of nuclei
Spore-producingstructures
Spores (n)
Mycelium
Meiosis
Germination
Germination
17.16 Fungi are classified into five groups
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Sexual reproductive structures are used to classify fungi
– Fungi with no known sexual stage are known as imperfect fungi
Fungi likely evolved from an aquatic, flagellated ancestor shared with animals
Chytrids, which have flagellated spores, are the earliest lineage of fungi
Animals and fungi diverged into separate lineages 1.5 billion years ago
The oldest fungal fossils are 460 million years old
Chytrids
Zygomycetes(zygote fungi)
Glomeromycetes(arbuscularmycorrhizal fungi)
Ascomycetes(sac fungi)
Basidiomycetes(club fungi)
17.16 Fungi are classified into five groups
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Zygomycetes
– Zygote fungi form resistant zygosporangia in which haploid spores form by meiosis
– This group includes black bread mold
17.16 Fungi are classified into five groups
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Glomeromycetes
– These fungi form mycorrhizae, in which invasive hyphae branch into treelike arbuscules within plant roots
– 90% of plants have symbiotic partnerships with glomeromycetes
17.16 Fungi are classified into five groups
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Ascomycetes
– Sac fungi form saclike asci, which produce sexual spores
– They range in size from yeasts to elaborate morels and cup fungi
– Some form lichens in association with green algae or cyanobacteria
17.16 Fungi are classified into five groups
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Basidiomycetes
– Club fungi are the mushrooms, puffballs, and shelf fungi
– They have club-shaped spore-producing structures called basidia
– These fungi are important forest decomposers
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17.17 Fungal groups differ in their life cycles and reproductive structures
Hyphae reproduce asexually by producing spores in sporangia at the tips of upright hyphae
When food is depleted, the fungus reproduces sexually
– Mycelia of different mating types join and produce a zygosporangium, which develops into a thick-walled structure that can tolerate dry, harsh conditions
– Under favorable conditions, the parental nuclei fuse and the diploid nucleus undergoes meiosis to form haploid spores
Zygosporangium (n + n)
Spores(n)
Diploid (2n)
Haploid (n)
Heterokaryotic (n + n)
Key
Meiosis
Mycelia ofdifferentmating types
Cells fuse
Youngzygosporangium(heterokaryotic)
Sporangium
2
1 Fusion ofnuclei
3
4
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17.17 Fungal groups differ in their life cycles and reproductive structures
Hyphae of different mating types fuse to form a heterokaryotic mycelium, which grows to produce a mushroom
– Haploid nuclei fuse to form diploid nuclei in the club-shaped cells called basidia that line the gills of the mushroom
– Each diploid nucleus undergoes meiosis to form haploid spores
Diploid (2n)
Haploid (n)
Heterokaryotic (n + n)
Key
Fusion of two hyphaeof different mating types
1
Diploid (2n)
Haploid (n)
Heterokaryotic (n + n)
Key
Fusion of two hyphaeof different mating types
1Growth ofheterokaryotic mycelium
2
Mushroom
Diploid (2n)
Haploid (n)
Heterokaryotic (n + n)
Key
Fusion of two hyphaeof different mating types
1Growth ofheterokaryotic mycelium
2
Mushroom
Diploid nuclei3
Basidia
Fusion ofnuclei
Diploid (2n)
Haploid (n)
Heterokaryotic (n + n)
Key
Fusion of two hyphaeof different mating types
1Growth ofheterokaryotic mycelium
2
Mushroom
Diploid nuclei3Fusion of
nuclei
Basidia
Meiosis
Haploidnuclei
Sporesreleased
4
Spores (n)
Diploid (2n)
Haploid (n)
Heterokaryotic (n + n)
Key
Fusion of two hyphaeof different mating types
1Growth ofheterokaryotic mycelium
2
Mushroom
Diploid nuclei3Fusion of
nuclei
Basidia
Meiosis
Haploidnuclei
Sporesreleased
4
Spores (n)
Germinationof sporesand growthof mycelia
5
17.18 CONNECTION: Parasitic fungi harm plants and animals
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80% of plant diseases are caused by fungi
– Between 10 and 50% of the world’s fruit harvest is lost each year to fungal attack
– A variety of fungi, including smuts and rusts, infect grain crops
Only 50 species of fungi are parasitic on animals, causing mycoses
– Human infections include athlete’s foot (caused by ringworm)
– Systemic mycoses are rare but serious fungal infections that spread through the body from inhaled spores
Ergots
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17.19 Lichens consist of fungi living in close association with photosynthetic organisms
Lichens consist of algae or cyanobacteria within a fungal network
– Many lichen associations are mutualistic
– The fungus receives food from its photosynthetic partner
– The fungal mycelium helps the alga absorb and retain water and minerals
Lichens are important pioneers on new land, where they help to form soil
– Lichens are sensitive to air pollution, because they obtain minerals from the air
Fungal hyphae
Algal cell
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Several species of ants and termites cultivate fungal gardens
The insects feed their fungi with leaves, weeding out undesirable fungi
– The fungi feed on the leaves
– The ants harvest the swollen hyphal tips
Farmer insects and fungal “crops” have been evolving together for over 50 million years
17.20 Some fungi have mutually beneficial relationships with ants
17.21 CONNECTION: Fungi have enormous ecological benefits and practical uses
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Fungi have many practical uses for humans
– Some fungi can break down toxic pollutants, including pesticides like DDT and cancer-causing chemicals
– Fungi may be able to clean up oil spills and chemical messes
– We eat many fungi, from mushrooms to cheeses modified by fungi
– Yeasts produce alcohol and cause bread to rise
– Fungi provide antibiotics that are used to treat bacterial disease
– Fungi are playing important new roles in molecular biology and biotechnology
PenicilliumStaphylococcusaureus
Zone ofinhibitedgrowth
Reproductive structures, as in flowers,contain spores and gametes
Cuticle covering leaves and stemsreduces water loss
Stomata in leaves allow gas exchangebetween plant and atmosphere
Lignin hardens cell walls of someplant tissues
Stem supports plant; may performphotosynthesis
Vascular tissues in shoots and rootstransport water, minerals, and sugars;provide support
Leaves carry out photosynthesis
Roots anchor plant; mycorrhizae (root-fungus associations) help absorb waterand minerals from the soil
ANCESTRALGREEN ALGA
1
2
3
a.
b.
c.
d.
A. Pine tree, a gymnosperm B. Puffball, a club fungus
You should now be able to
Copyright © 2009 Pearson Education, Inc.
1. Describe the key plant adaptations for life on land
2. Describe the alternation of generation life cycle; explain why it appears that this cycle has evolved independently in algae and land plants
3. Describe the key events of the moss, fern, and pine life cycles
4. Explain how coal was formed; explain why coal, oil, and natural gas are called fossil fuels
You should now be able to
Copyright © 2009 Pearson Education, Inc.
5. Describe the parts of a flower and explain their functions
6. Describe the stages of the angiosperm life cycle
7. Describe angiosperm adaptations that promote seed dispersal
8. Explain how flowers are adapted to attract pollinators
9. Compare the life cycles and reproductive structures in the fungal groups
You should now be able to
Copyright © 2009 Pearson Education, Inc.
10. Describe the structure and characteristics of lichens
11. Describe the positive ecological and practical roles of fungi