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Plant Reproduction. Sexual reproduction. The mixing of genetic material from two parents to produce offspring Offspring are genetically different from parents. Plants. Flowers are the sexual reproductive structures in plants. Draw and Label this diagram!. Lily flower. Ecological strategy:
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Sexual reproduction • The mixing of genetic material from two parents to produce offspring • Offspring are genetically different from parents
Plants • Flowers are the sexual reproductive structures in plants
Lily flower • Ecological strategy: • Insect pollinated flower targeting bees in particular
Lily advantages The reward and display make it very likely that pollen from one lily plant will reach another lily plant
Lily flower • Draw flower, note projections and markings on petals.
Lily flower • Stigma protrudes in front of stamens so insect touches stigma and deposits pollen from another flower first!
Adaptations for pollinator • Spikes on petals force pollinator past anthers on way to nectary
Adaptations for pollinator • Stigma is above anthers so pollinator deposits pollen from another flower before it gets pollen from this flower
Adaptations for pollinator • Anthers are large so pollen eating bees won’t destroy them, enough pollen for bee and cross pollination
Adaptations for pollinator • Highly scented nectar because bees have a good sense of smell.
The flower at the right shows how UV markings may guide insect to nectary past anthers
disadvantages • Huge energy cost (nectar and showy flower) • Insects can’t fly in bad weather • Relies mainly on bees so if they become extinct then no cross pollination.
Adaptations for environment • Grow in sheltered environments • Bloom in warm season spring or summer • Petals won’t get ruined by wind • Cold blooded insects need warmth to fly • Bees can’t fly in windy weather, bad weather • Longer days for more time to pollinate
Your turn - Questions • Describe the difference in function between the sepals and the petals. • The Stamen is the male reproductive structure consisting of the anther and the filament, Describe how the pollen in the anther may get distributed. • Describe two ways a flower encourages cross pollination from a bee or bird. • Describe why there is some distance between the stigma and the ovary. • Name some adaptations angiosperms have made to increase their chance of survival. • Name some disadvantages of the way angiosperms reproduce.
Answers • The sepals protect the young flower bud whereas the petals are to attract pollinators. • Wind blows pollen from the flowers anther to other flowers stigma. • Bees or other animals such as birds collect nectar and in the process transfer pollen to other plants. • The nectar in flowers smell good to attract animals that assist in cross pollination
Answers-Adaptations • Spikes on petals force pollinator past anthers on way to nectary. • Stigma is above anthers so pollinator deposits pollen from another flower before it gets pollen from this flower • Anthers are large so pollen eating bees won’t destroy them, enough pollen for bee and cross pollination • Highly scented nectar because bees have a good sense of smell • The flower has UV markings that guide the insect to the nectary past the anthers • Pollen is spikey to stick to insect hairs
Answers cont.. • The bees love nectar so encourage them to come back to the flower and pollinate it and other flowers. • The stigma needs to be up high so it can be pollinated and the ovary needs to be somewhere less exposed so that it can be protected.
Answers-Disadvantages • Huge energy cost (nectar and showy flower) • Insects can’t fly in bad weather • Relies mainly on bees so if they become extinct then no cross pollination.
Question-Homework • Discuss the advantages and disadvantages of the reproductive system of an angiosperm.