lorraine kuun, july 2011 adaptations of salvia for insect pollination by bees landing platform...
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Lorraine Kuun, July 2011
Adaptations of Salvia for insect pollination by bees
Landing platform
Nectar guides
Tubular shape, contains nectar
Stamens form “lever”
Pistil overhanging landing platform
Bees attracted to blue and yellow flowers
• 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 flowers for bird pollination
Lorraine Kuun, July 2011
Adaptations of Strelitzia for pollination by birds
Bright colours
Nectaries
Sturdy landing platform
Stigma close to pollen
Stamens fused in tube to fit beak
Lorraine Kuun, July 2011
Lorraine Kuun, July 2011
Lorraine Kuun, July 2011
• 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
Adaptations for wind pollination
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