Plant Reproduction
I n a nutshel l
AP Biology
2007-2008
Plant Diversity fern
mosse s
s
conifer s
flowering plants
Bryophytes
Pteridophytes
Gymnosperm
Angiosperm
non-vascular land plants
seedless vascular plants
pollen & “naked� seeds
flowers & fruit
flowers & fruits
pollen & seeds
vascular system AP Biology
common
xylem cells tracheids
Animal vs. Plant life cycle Animal
Plant
diploid multicellular individual 2n mitosis
meiosis
fertilization haploid unicellular gametes 1n AP Biology
diploid multicellular sporophyte 2n mitosis fertilization
meiosis
gametes 1n
spores 1n
mitosis
mitosis haploid multicellular gametophyte 1n
alternation of
Bryophytes Mosses & liverworts non-vascular diploid swimming sperm multicellular dominant haploid gametophyte sporophyte dependent sporophyte 2n mitosis spores for reproduction meiosis fertilization
gametes 1n
spores 1n
mitosis
mitosis haploid multicellular gametophyte 1n
AP Biology alternation of
Pteridophytes Ferns vascular swimming sperm dominant sporophyte independent gametophyte
fragile
spores for reproduction
haploid archegonia
antheridia AP Biology alternation of
diploid multicellular sporophyte 2n mitosis fertilization
meiosis
gametes 1n
spores 1n
mitosis
mitosis haploid multicellular gametophyte 1n
Gymnosperm Conifers vascular diploid pollen (sperm) multicellular dominant sporophyte sporophyte dependent reduced gametophyte 2n mitosis cones, seeds for reproduction meiosis fertilization
mal e AP Biology
femal e
gametes 1n
spores 1n
mitosis
mitosis haploid multicellular gametophyte 1n
Angiosperm Flowering plants vascular pollen (sperm) diploid multicellular dominant sporophyte sporophyte dependent reduced gametophyte 2n mitosis flowers, fruits, seeds for meiosis fertilization reproduction
male gametophyte in pollen (haploid)
female gametophyte in ovary (haploid) AP Biology
gametes 1n
spores 1n
mitosis
mitosis haploid multicellular gametophyte 1n
Angiosperm: flowering plants
AP Biology
Angiosperm life cycle male gametophyte in pollen (haploid)
polar nuclei pollen grains
egg cell
fertilization
female gametophyte in ovary (haploid)
AP Biology
sporophyte in seed (diploid)
Flower Modified shoot with 4 rings of modified leaves sepals Stamen petals stamens
Stigma Style Ovary
Anther Filament
male pollen
carpel female egg
AP Biology
Carpel
sepals petals stamens
Petal Ovule Sepal
carpel
Double Fertilization
Wha t’s the a da pti ve a dva nta ge?
pollen grain sperm cells
pollination
pollen tube
ovule
Endosperm (3n)
ovary endosperm (3n) pollen tube polar nuclei egg cell AP Biology
food in seed grains beans coconut
milk zygote (2n)
Seed & Plant embryo Seed offers… protection for embryo stored nutrients for growth of embryo
cotyledons = “seed” leaves, first leaves of new plant AP Biology
seed coat
endosperm 3n cotyledons embryo
Identify the flower structures‌
AP Biology
Flower variations
AP Biology
Corn reproduction
seeds
flowers & seeds silk→stigma & style
AP Biology
female→carpel
tassel
pollen
male→stamens
Co-evolution: flowers & pollinators
How a bee sees a flower‌insects see UV light = a bulls-eye to the nectar
AP Biology
Angiosperm: fruiting plants
AP Biology
Other fruits‌
AP Biology
Fruit development Peach, plum, apricot, cherry
AP Biology
1 flower : 1 carpel : 1 ovary : 1 seed
Fruit development Apple, pear
AP Biology
1 flower : 5 carpels : many ovaries : many seeds
Fruit development  Citrus fruit ď ľ
AP Biology
1 flower : many carpels : many ovaries : many seeds
Fruit development Raspberry, strawberry
AP Biology
1 flower : many ovaries : many seeds
Seed dispersal  Plants produce enormous numbers of seeds to compensate for low survival rate ď ľ
vast amount of genetic variation for natural selection to screen
r-strategy
AP Biology
K-strategy
Any Questions??
AP Biology
2007-2008