Sexual Reproduction in Flowering Plants
Stamen
● Anther – pollen producing organ of the flower
● Filament – slender stalk supporting the anther
● Stigma – the sticky, receptive tip of the pistil
that is responsible for catching the pollen
● Style – the tube-shaped connection between the
stigma and ovule
● Ovule – the structure that contains the female
reproductive cells
Petals Brightly coloured modified leaves, which function to
attract pollinators
Sepal Outer covering which protects the flower when in bud
flowerSexual Reproduction in Flowering Plants
OUTBREEDING DEVICES
Unisexuality The plant may be unisexual, which means it may exhibit either male or female gametes.
Dichogamy The stamens and carpels of a bisexual flower mature at different times,
Protandrous: The androecium matures earlier than the gynoecium. (e. g., sunflower)
Protogynous: The gynoecium matures earlier than the androecium.(e.g., Michelia)
Herkogamy When some form of physical barrier makes self pollination impossible.
Examples: In Cruciferae, the stigma extends far beyond the stamens so that the pollen from the
stamen are not likely to reach the stigma
Self- Sterility In some plants a flower cannot be fertilized by pollen of the same plant or same flower due
to genetic reasons. E.g., Solanum. Nicotiana etc.
Heterostyly The condition (e.g. in primroses) of having styles of different lengths relative to the stamens
in the flowers of different individual plants, to reduce self-fertilization
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