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SEXUAL REPRODUCTION IN FLOWERING PLANTS:
Introduction:
We know that in angiosperms, parent plant is
diploid sporophyte generation
...
The
flower components are arranged in the form of
whorls
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Calyx: is the outer most whorl
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Its individual units (leaflets) are called
sepals
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Corolla is the next inner whorl and is often coloured
brightly
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They serve to attract bees, birds, etc
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|the flower is actually a condensed shoot with the
nodes present very close to each other
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All the structures present at one node are
collectively called the whorl|
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e androecium is the male reproductive
part of flower
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Each
stamen has a thread-like filament at the free end of
which anther is attached
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Each microspore
germinates into the male gametophyte generation
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e a tube nucleus
And a generative nucleus
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All
these structures are the male gametophyte
generation of plant
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e gynoecium is the female
reproductive part of flower
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Each carpel is made up of the
basal ovary, middle style and upper stigma
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Inside each

value, one haploid macrospore is produced through
meiosis
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During it, macrospore
undergoes mitosis and produces an egg cell and
some associated structures (e
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Egg
cell and associated structures are the female
gametophyte generation of plant
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These
may either be fused or free|
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He laid a solid foundation of
botany including the morphology and functions of
the flowers
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When pollen grains mature, they are transferred to
stigma
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On reaching the
stigma, the tube nucleus of pollen grain constructs a
Pollen tube
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The tube grows through
style and ovary and enters ovule
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Both sperms enter the female
gametophyte
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The other sperm fuses with diploid
fusion nucleus and forms a triploid (3N) nucleus
called Endosperm nucleus
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Zygote develops into embryo and endosperm
nucleus develops into endosperm tissue (food of
the growing embryo)
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When seeds mature,
they are dispersed, if seeds get suitable conditions,
their embryos develop into new plants ( the diploid
sporophytes of the next generation)
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Types: two types of pollination are recognized
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➢ Cross Pollination: is the transfer of pollen
grains from the flower on one plant to the
flower on other plant of the same species
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The insect pollinated and wind pollinated
flowers have st

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