FLOWERS AS REPRODUCTIVE STRUCTURES Lorraine Kuun, July 2011

The Angiosperm flower Lorraine Kuun, July 2011

Male and female whorls The stamens are the male organs and produce pollen that contain the male gametes The pistil with the stigma, style and ovary is the female organ of the plant. The ovum is found in the ovule. Lorraine Kuun, July 2011

POLLEN, BEARERS OF MALE GAMETES Stamens consist of an anther with a filament. The anther produces pollen in the pollen sac. The pollen grains contain the male gametes. Lorraine Kuun, July 2011

POLLINATION is the transfer of ripe pollen from the anther to a receptive stigma of a flower of the same species Lorraine Kuun, July 2011

1.Self pollination 2. Geitonogamy 3.Cross-pollination Lorraine Kuun, July 2011

POLLINATORS Most pollinators are insects e.g. Bees, moths, butterflies, beetles. Some vertebrates also pollinate flowers e.g. Bats, mice, birds (mainly). Many flowers are pollinated by wind. Lorraine Kuun, July 2011

Bright colours (bees cannot see red), white for night pollinators e.g. moths Often sweet scent (attracts moths and butterflies) Reward of nectar and pollen Contrasting markings on petals to locate centre of flower (usually not visible to human eye – ultraviolet) Pollen cling to hair on insect bodies Flower adapted for insect pollination Lorraine Kuun, July 2011