ANGIOSPERMS The flowering plants Spring crocus Crocus vernus © P. Billiet © 2016 Paul Billiet ODWS

Flower structure Flowers are reproductive structures Adapted to send and receive pollen from one flower to another of the same species pollination Flowers = a series of modified leaves These leaves are arranged in rings (whorls). © 2016 Paul Billiet ODWS

Types of pollination Wind Animal Water Bumble bee Bombus hortorum on red clover Trifolium pratense © P. Billiet Yorkshire fog grass Holcus lanatus © P. Billiet © 2016 Paul Billiet ODWS

Animal pollination Usually insects Also other flying animals e.g. hummingbirds or fruit bats. Cerambycid beetle pollinating bramble Rubus fruticosus © P. Billiet © 2016 Paul Billiet ODWS

Flower structure Dog rose Rosa canina © 2016 Paul Billiet ODWS © P. Billiet © P. Billiet © P. Billiet Dog rose Rosa canina © 2016 Paul Billiet ODWS

Flower structure Stigma Style Ovary Petal Anther Sepal Filament © 2016 Paul Billiet ODWS

Pollination Pollen grains contain the male gametes Yellow archangel Lamiastrum galobdolon being pollinated by a bumble bee Bombus hortorum © P. Billiet Pollination Pollen grains contain the male gametes 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 © 2016 Paul Billiet ODWS

Pollination Small skipper Thymelicus flavus on marsh thistle Cirsium palustris © P. Billiet © 2016 Paul Billiet ODWS

Pollination The honey bee Apis melifera on marsh thistle Cirsium palustris © P. Billiet © 2016 Paul Billiet ODWS

Pollination Some flowers are highly specialised to encourage only one type of insect Fox glove flowers Digitalis purpurea © P. Billiet © 2016 Paul Billiet ODWS

Pollination Most flowering plants are hermaphroditic self pollination possible cross pollination preferred. © 2016 Paul Billiet ODWS

Fertilisation Pollen grain Stigma Style Ovule Embryo sac Ovary Pollen tube Ovary © 2016 Paul Billiet ODWS

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 flower The pollen grain germinates on the stigma It grows a pollen tube down the style Male nuclei travel down the pollen tube to the ovule. © 2016 Paul Billiet ODWS

Fertilisation Embryo sac Polar nuclei Egg cell Micropyle © 2016 Paul Billiet ODWS

Fertilisation Pollen grains of the daisy Bellis perennis © P. Billiet © P. Billiet © 2016 Paul Billiet ODWS

Fertilisation Germinating pollen grains of blue bell, Hyacinthoides non-scripta © P. Billiet © P. Billiet © 2016 Paul Billiet ODWS

From flower to fruit Marsh marigold Caltha palustris © P. Billiet © P. Billiet © P. Billiet Marsh marigold Caltha palustris © 2016 Paul Billiet ODWS

Fruits and seed dispersal Animal dispersal Strawberry Fragaria vesca © P. Billiet Explosive dispersal Bird’s foot trefoil Lotus corniculatus © P. Billiet Animal dispersal Wood avens Geum urbanum © P. Billiet Wind dispersal Ragwort Senecio © P. Billiet © 2016 Paul Billiet ODWS