First seed plants

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First seed plants

• Gymnosperm conifers
• vascular
• heterospory
• male vs. female gametophytes
• seeds
• naked seeds (no fruit)
• pollen
• contain male gametophyte
• life cycle dominated by sporophyte stage
• coniferous trees you are familiar with are
  diploid
• reduced (microscopic) gametophyte
• reduction of gametophyte protects delicate egg
  embryo in protective sporophyte
• protected from drought UV radiation

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Early Gymnosperm ginkgo
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Early Gymnosperm cycads
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Gymnosperm conifers
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Cones naked seeds
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male (pollen) cones
female cones
Male cone
pine embryo
Female cone
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Pine Life Cycle
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Pollen

• Pollen eliminated the requirement for water for
  fertilization
• spread through wind animal
• Pine pollen below angiosperm pollen

Where canconifers live?
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First flowering plants

• Angiosperm flowering plants
• vascular
• heterospory
• male vs. female gametophytes
• flower
• specialized structure for sexual reproduction
• seeds within fruit
• pollen
• life cycle dominated by sporophyte stage
• trees bushes you are familiar with are diploid
• reduced (microscopic) gametophyte

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Angiosperm flowering plants
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Angiosperm life cycle
male gametophyte pollen grain (haploid)
ovary sac
sperm nuclei travel down pollen tube
female gametophyte ovary sac (haploid)
doublefertilization
new sporophytein seed (diploid)
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Flower

• Modified shoot with 4 ringsof modified leaves
• sepals
• petals
• stamens
• male
• carpel
• female

adaptations through mutations
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Identify the flower structures
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Flower variations
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Co-evolution flowers pollinators
How a bee sees a flowerinsects see UV light a
bulls-eye to the nectar
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Angiosperm fruiting plants
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Other fruits
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Seed Plant embryo
seed coat

• Seed offers
• protection for embryo
• stored nutrients for growth of embryo

endosperm (3n)
cotyledons
embryo (2n)
cotyledons seed leaves, first leaves of new
plant
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Monocots dicots

• Angiosperm are divide into 2 classes
• dicots (eudicot)
• 2 cotyledons (seed leaves)
• leaves with network of veins
• woody plants, trees, shrubs, beans
• monocots
• 1 cotyledon
• leaves with parallel veins
• grasses, palms, lilies

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Any Questions??