Sexual Reproduction in Flowering Plants

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Sexual Reproduction in Flowering Plants
Visit http//koning.ecsu.ctstateu.edu/Plants_Huma
n/lecppt/flower.ppt
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Alternation of Generations in Plants
Life Cycle of a Typical Animal
Life Cycle of a Typical Plant
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Flowers and Fossils
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The Rise and Fall of Dinosaurs

• Dinosaurs are found in the fossil record starting
  about 230 million years ago.
• The last dinosaurs bcame extinct about 65 million
  years ago.
• Impact Hypothesis A 10km-wide meteorite had
  smashed into the Yucatan peninsula in Mexico
  causing worldwide forest fires tsunamis several
  kilometres high and an impact winter

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The Rise and Fall of Dinosaurs

• Evidence prior to impact that diversity of
  dinosaur species was on the decline.
• Climate change
• Rise of Angiosperms
• Sometime in the Mid- Cretaceous Period between
  144 to 65 Million Years Ago
• Corresponds with a decline of the gymnosperms and
  rise of animal groups

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Why Dinosaurs Went Extinct!
The Far Side by Gary Larson.
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Basic Flower Structure
stigma
carpel
gynoecium
Flower is perfect Flower is monoecious
locule
style
pollen
ovary
ovule
anther
filament
stamen
androecium
petal
corolla
perianth
sepal
receptacle
calyx
Perianth is complete
pedicel
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Some Example Stories
Perfect Flowers Pea exclusively
self-pollinating Hibiscus self-pollinating
if not crossed Cherry self-incompatible
only outcrosses Imperfect Flowers Begonia
unisexual but monoecious Holly
unisexual and dioecious Variable Cucumber male
perfect female parthenocarpic
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Basic Flower Structure
stigma
carpel
Pistil is simple
gynoecium
Flower is perfect Flower is monoecious
locule
style
pollen
ovary
ovule
anther
superior
filament
stamen
Flower is hypogynous
androecium
petal
corolla
perianth
sepal
receptacle
calyx
Perianth is complete
pedicel
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Ovary Superior Flower Hypogynous
Flower Perigynous
Ovary Half-Superior
Ovary Half-Inferior
Flower Epigynous Ovary Inferior
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Flower Structure - review
Ranunculus acris - buttercup
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Basic Flower Structure
stigma
carpel
Pistil is simple
gynoecium
Flower is perfect Flower is monoecious
locule
style
pollen
ovary
ovule
anther
superior
filament
stamen
Flower is hypogynous
androecium
petal
corolla
perianth
sepal
receptacle
calyx
Perianth is complete
pedicel
This longitudinal section view does not allow us
to consider symmetry
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Flower Formula Symbol Sequence to Diagram Flower
Symmetry radial bilateral

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5 5
5 5 5
5 5
Number of Parts per Whorl

• sepals in calyx

• petals in corolla

• stamens in androecium

• carpels in gynoecium

Fusion within whorl curved line over number
Fusion between whorls square bracket below
numbers
Attachment of flower parts relative to
ovary horizontal line
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Ovary Superior Flower Hypogynous
Flower Perigynous
Ovary Half-Superior
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Ovary Half-Inferior
Flower Epigynous Ovary Inferior