plant reproduction - king's science...
TRANSCRIPT
AP Biology 2007-2008
Plant Reproduction
In a nutshell
AP Biology
Plant Diversitymosses ferns conifers flowering plants
xylem cells
tracheids
Bryophytesnon-vascular
land plants
Pteridophytesseedless
vascular plants
Gymnospermpollen &
“naked” seeds
Angiospermflowers & fruit
common ancestor
vascular system
pollen & seeds
flowers & fruits
AP Biology
Animal vs. Plant life cycle
diploidmulticellular
individual2n
diploidmulticellularsporophyte
2n
haploidmulticellulargametophyte
1n
haploidunicellulargametes
1n
spores1n
gametes1n
Animal Plant
alternation of generations
meiosis
fertilization
mitosis meiosis
mitosismitosis
fertilization
mitosis
AP Biology
Bryophytes
diploidmulticellularsporophyte
2n
haploidmulticellulargametophyte
1n
spores1n
gametes1n
alternation of generations
meiosis
mitosismitosis
fertilization
mitosis
Mosses & liverworts
Seedless, non-vascular
swimming sperm
dominant haploid gametophyte
dependent sporophyte
spores for reproduction
AP Biology
Pteridophytes
diploidmulticellularsporophyte
2n
haploidmulticellulargametophyte
1n
spores1n
gametes1n
alternation of generations
meiosis
mitosismitosis
fertilization
mitosis
Ferns
Seedless, vascular
swimming sperm
dominant sporophyte
independent gametophyte
fragile
spores for reproduction
haploid
archegonia
antheridia
AP Biology
Conifers
Naked seeds, vascular
pollen (sperm)
dominant sporophyte
dependent reduced gametophyte
cones, seeds for reproduction
Gymnosperm
diploidmulticellularsporophyte
2n
haploidmulticellulargametophyte
1n
spores1n
gametes1n
meiosis
mitosismitosis
fertilization
mitosis
male
female
AP Biology
Flowering plants
vascular
pollen (sperm)
dominant sporophyte
dependent reduced gametophyte
flowers, fruits, seeds for
reproduction
Angiosperm
diploidmulticellularsporophyte
2n
haploidmulticellulargametophyte
1n
spores1n
gametes1n
meiosis
mitosismitosis
fertilization
mitosis
femalegametophyte
in ovary(haploid)
malegametophyte
in pollen(haploid)
AP Biology
Angiosperm: flowering plants
AP Biology
Angiosperm life cycle
femalegametophyte
in ovary(haploid)
malegametophyte
in pollen(haploid)
sporophytein seed(diploid)
fertilization
polarnuclei
eggcell
pollengrains
AP Biology
Anther
FilamentStamen
Stigma
Style
Ovary
Carpel
Sepal
Petal
Ovule
sepals
petals
Flower
Modified shoot with 4 rings
of modified leaves
sepals
petals
stamens
male
pollen
carpel
female
egg
stamens
carpel
AP Biology
Double Fertilization
ovule
pollinationsperm cells pollen tube
pollen grain
zygote (2n)polarnuclei
egg cell
endosperm (3n)
Endosperm (3n)
food in seed
grains
beans
coconut milk
What’s theadaptive
advantage?
pollen tube
ovary
AP Biology
Seed & Plant embryo
Seed offers…
protection for
embryo
stored nutrients
for growth of
embryo
seed coat
endosperm
3n
cotyledons
embryo
cotyledons = “seed” leaves,
first leaves of new plant
AP Biology
Identify the flower structures…
AP Biology
Flower variations
AP Biology
Corn reproduction
flowers &
seeds
malestamensfemalecarpel
seeds
pollensilkstigma & style tassel
AP Biology
Co-evolution: flowers & pollinators
How a bee sees a flower…insects 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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Fruit development
Peach, plum, apricot, cherry
1 flower : 1 carpel : 1 ovary : 1 seed
AP Biology
Fruit development
Apple, pear
1 flower : 5 carpels : many ovaries : many seeds
AP Biology
Fruit development
Citrus fruit
1 flower : many carpels : many ovaries : many seeds
AP Biology
Fruit development
Raspberry, strawberry
1 flower : many ovaries : many seeds
AP Biology
Seed dispersal R-strategy: make lots of offspring; little investment; high mortality
K-strategy: make fewer offspring, but invest more; lower mortality
Many plants produce enormous numbers of seeds to compensate for low survival rate
vast amount of genetic variation for natural selection to screen
r-strategy K-strategy
AP Biology 2007-2008
Any
Questions??