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Biology pollinated
- 2. Introduction • Structure andadaption of insect pollinated flowers • Structure and adaption of wind pollinated flowers • Growth of the pollen tube followed by fertilization • Summary
- 3. Structure of insectpollinated flowers and its adaption for pollination • Stamens inside the flower to make the insect touch • Stigma inside the flower to make the insect touch • Stigma is sticky to make the pollen grins attach from the insect • Petals are large to attract insects • Petals are brightly colored to attract insects • Nectaries produce nectar (Like Sugar) to reward the insect for pollinating the flower • Pollen grains are large and sticky so that grains stick to the insect
- 4. Structure of windpollinated flowers and its adaption for pollination • Stamens loosely connected and exposed so the wind can easily take it away • Stigma exposed to catch pollen blowing in the wind • Stigma feathery to catch pollen grain blowing in the wind • Small dull colored petals has no need to attract insects or living helpers • Nectaries are not present doesn't have to reward any living helper • Pollen grains are small, smooth and inflated so the wind can easily take it away
- 5. Growth of thepollen tube followed by fertilization Seeds Nucleus of pollen must fuse with nucleus of ovum (egg) 1. Pollen grain grows a tube 2. Tube digests its way through style to ovary 3. Tube grows around ovule 4. Tip of tub dissolves 5. Grain moves out of tube into ovule 6. Grain fertilises ovum (egg)
- 6. Summary What we learntfrom this project is: • Flower need help from insects to pollinate and fertilise. • Flowers are colorful, smell nice and have nectar to attract and reward insects for their hard work • Other plant use the wind to pollinate and fertilise. • Little grains loosely attached outside of the plant so wind can easily blow them away • The grain fertilises the egg by growing a tube that digests a path to the ovum (egg)
Editor's Notes
- #2 Firstly, let me welcome you all to our presentation today.We will be talking about PollinationIf you have any questions, please keep them until the end of the presentation.
- #3 This presentation is about reproduction in plants. We will focus on the following aspects of pollination.First we will talk about the structure of insect pollinated flowers and how these structures encourages insects to pollinate the flower.Secondly we will describe the structure of wind pollinated flowers and how the structure is suited to wind pollination.Then we will look at how firtilisation takes place by using a pollen tube.Finally we will summarise the main points and answer questions.
- #4 If you look closely at the picture of a typical insect pollinated flower you will notice the stamens and sticky stigma are protected inside the flower by large fragrant, colourful petals.This attracts insects and forces them to enter the flower so that they touch the stamens and stigma so that grains are exchanged. We say cross pollination occurs when grains from one flower are exchanged for grains in another flower.The insect is rewarded with nectar (sugar) for all its hard work.
- #5 If you look closely at this image of a wind pollinated flower you will notice that the stamens and feathery stigma are exposed. Notice also that the stamens are only loosely attached. The pollen grains are small, smooth and inflated. All of these properties exist so the wind can easily blow pollen away from the plant and catch grains from other plants carried in the wind. In contrast to insect pollinated flowers, wind pollinated flowers look dull they are not colorful and tend to be a verity of greens. Also there is no nectaries as their no need to attract or reward insect for their hard work.
- #6 Once the pollen grain has entered another plant, either by wind or by insect, nucleus of pollen must fuse with the nucleus of the ovum. This proses is called fertilisation and is achieved in a number of steps. Firstly pollen grain grows a tube.Secondly tube digests its way through style to ovary.Third tube grows around ovule.Then Tip of tube dissolves.After that grain moves out of tube into ovule.And finally grain fertilises ovum (egg)
- #7 What we learnt from this project is:Flower need help from insects to pollinate and fertilise.Flowers are colorful, smell nice and have nectar to attract and reward insects for their hard workOther plant use the wind to pollinate and fertilise. Little grains loosely attached outside of the plant so wind can easily blow them awayThe grain fertilises the egg by growing a tube that digests a path to the ovum (egg)