1. ANGIOSPERMS The flowering plants Spring crocus Crocus vernus

2. Flower structure  Flowers are reproductive structures  The have evolved to send and receive pollen from one flower to another  This is process of pollination  Flowers are developed from a series of modified leaves  These leaves are arranged in a rings (whorls)

3. Types of pollination  Wind  Animal  Water Bumble bee Bombus hortorum on red clover Trifolium pratense Yorkshire fog grass Holcus lanatus

4. Animal pollination  Usually insects  Also other flying animals  e.g. hummingbirds or fruit bats Cerambycid beetle pollinating bramble Rubus fruticosus

5. Flower structure Dog rose Rosa canina

6. Flower structure Stigma Style Ovary Petal Sepal Filament Anther

7. Pollination  Pollen grains contain the male gametes of the plant  They are picked up by a pollinator and transferred to another flower  Plants tend to specialise in pollinators  This ensures the pollen is delivered to same species of plant Yellow archangel Lamiastrum galobdolon being pollinated by a bumble bee Bombus hortorum

8. Pollination Small skipper Thymelicus flavus on marsh thistle Cirsium palustris

9. Pollination The honey bee Apis melifera on marsh thistle Cirsium palustris

10. Pollination  Some flowers are highly specialised to encourage only one type of insect Fox glove flowers Digitalis purpurea

11. Pollination  Most species of flowering plants are hermaphroditic  Pollen from a flower could land on the stigma of the same flower or another flower on the same plant = self pollination  Pollen transferred from the anther on one flower to the stigma of another flower on a different plant = cross pollination

12. Fertilisation  Pollination ≠ Fertilisation  The male gamete (the male nucleus) has to get to the egg cell  The egg cell lies in an ovule in an ovary at the centre of the plant  The pollen grain germinates on the stigma  It grows a pollen tube down the style  It male nuclei travel down the pollen tube to the ovule

13. Fertilisation Style Stigma Pollen grain Ovule Embryo sac Pollen tube Ovary

14. Fertilisation Egg cell Polar nuclei Embryo sac Micropyle

15. Fertilisation Pollen grains of the daisy Bellis perennis

16. Fertilisation Germinating pollen grains of blue bell, Hyacinthoides non-scripta

17. The double fertilisation Pollen tube Pollen tube entering micropyle Male nucleus + egg cell = zygote (2n) Male nucleus + 2 polar nuclei = endosperm nucleus (3n) Ovule Nucellus

18. From flower to fruit Marsh marigold Caltha palustris

19. Fruits and seed dispersal Animal dispersal Strawberry Fragaria vesca Wind dispersal Ragwort Senecio Explosive dispersal Bird’s foot trefoil Lotus corniculatus Animal dispersal Wood avens Geum urbanum