Adaptations of Salvia for insect
pollination by bees
Stamens form “lever”
Pistil overhanging
landing platform
Tubular shape,
contains nectar
Nectar guides
Landing platform
Bees attracted to blue and yellow flowers
Lorraine Kuun, July 2011
Adaptations of flowers for bird
pollination
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High yield of dilute nectar
Bigger than most insect-pollinated flowers
Open in daytime, often red
Sturdy against rough feeding of birds
Little or no scent – birds have poor sense of smell
Protect ovary against beaks by being inferior or
by partition
• Pollen sticks together in clumps
• Often erect or with landing platform for birds that
do not hover
Lorraine Kuun, July 2011
Adaptations of Strelitzia for pollination
by birds
Stigma close to pollen
Stamens fused in
tube to fit beak
Bright colours
Nectaries
Sturdy landing platform
Lorraine Kuun, July 2011
Lorraine Kuun, July 2011
Lorraine Kuun, July 2011
Lorraine Kuun, July 2011
Adaptations for wind pollination
• Flowers do not have scent, nectar or brightly
coloured petals – no need to attract pollinators.
• Flowers high on plant to be exposed to wind.
• Flowers usually small and reduced, lacking calyx
or corolla (sepals and petals).
• Anthers large and well-exposed.
• Masses of light, non-sticky pollen produced.
• Stigmas long and feathery with large area for
trapping pollen.
Lorraine Kuun, July 2011
Lorraine Kuun, July 2011
Lorraine Kuun, July 2011
The pollen grain germinates
• Meiosis occurs in the
pollen grain.
• The male gametes are
haploid.
• When the ripe pollen
grain lands on a receptive
stigma, it will germinate.
• The pollen grain
germinates and form a
pollen tube.
Lorraine Kuun, July 2011
The germinated pollen grain is the male
gametophyte
Lorraine Kuun, July 2011
The female
pistil
• The ovary contains the
ovule(s) with female
gametes (n).
• The pollen tube grows
down the style, through
the micropyle and into
the embryo sac.
• Double fertilisation
occurs.
Lorraine Kuun, July 2011
The female gametophyte:
germ sac with 8 nuclei
Lorraine Kuun, July 2011
Lorraine Kuun, July 2011