POLLINATION

1.  J. and A. Bebbington 2004 This presentation may be used only by recognised educational institutions POLLINATION 1

2. stigma stamen In flowering plants, pollination is the carrying of pollen from the stamens (male part of the flower) to the stigma (on the female part of the of flower).

3. On the stigma the pollen grain grows a pollen tubedown the style into the ovary.Fertilisation takes place when the pollen tube and the ovule come together. stigma POLLINATION style stamen ovary FERTILISATION ovule After fertilisation the ovule develops into a seed.

4. There is an enormous variety in the size, colour shape and even smell of flowers.This is related to the way in which they are pollinated. Bee orchid Sweet Vernal-grass Marsh-marigold Honeysuckle

5. bright red stigmas of female flowers male flowers in catkins In Britain pollen is usually carried either by wind or insects. Wind-pollinated flowers, like the male Hazel flowers shown here, are often small, and borne in long dangly catkins. These are blown about by the wind, releasing large amounts of pollen.

6. Here a hazel catkin shows the large amount of pollen shaken out of it as it moves. Pollen being blown around in the wind may not find a stigma and will be wasted. Wind-pollinated plants produce a lot of pollen and this increases the chance of success.

7. feathery stigma which sweeps pollen from the air stamens with long dangling stalks In June and July, it is often the grasses, releasing very large amounts of pollen, which cause problems for hay fever sufferers

8. spur containing nectar Insects visit flowers to find food, e.g. nectar. In the Butterfly-orchid nectar is stored in a long tube (the spur) which is part of the petal.

9. Many insects feed on pollen. This bee is collecting pollen in its pollen basket to feed to its larvae. pollen basket

10. As an insect moves from flower to flower, pollen stuck to its body has a good chance of landing on a stigma. pollen

11. The next few pictures show you a few examples of how flowers, like the Foxglove shown here, are adapted to their pollinating insects

12. The Foxglove flower is just the right size for a bumblebee to fit inside. bee going into foxglove

13. stamen As the bee squeezes into the Foxglove flower its back brushes against the stamens and stigma. Smaller insects can’t enter the flower because of the long hairs at the entrance. stigma hairs

14. The Evening Primrose is pollinated by moths flying in the evening. The luminous yellow petals are easily seen in the dusk. Sticky chains of pollen cling to the visiting moths.

15. Broom is designed to be pollinated by heavy insects like bees. The male and female parts are all tightly packed into the keel. When a heavy insect lands on the wings, they are pushed downwards and the bee hits the keel, which then explodes! wing wing keel

16. The stamens, style and stigma whizz round the insect both collecting and covering it with pollen.

17. Most insect-pollinated flowers are large and brightly coloured so that insects can easily find them. If they are small they may be grouped together to look like a large flower as in this Dandelion.

18. Can you think why not many British wild flowers are red? 18

19. Many insects do not see red well, so it would not be a good colour to use to attract them. 19