DESIGN A FLOWER Design a Flower is a module to teach students about pollination, the structures involved in pollination and the different animals that are responsible for assisting the process. They will also learn why all flowers look different from each other – they are designed to attract different pollinators! After learning about what pollination is and how it happens, students will be asked to select a pollinator from the pollinator playing cards (or you can hand them out to the students to add an element of surprise). These cards detail the characteristics which their specific pollinator finds most attractive in a flower, as well as giving the student interesting facts about their animal and its function as a pollinator. The student is then asked to design their own flower based on what is on the card and should be encouraged to be as imaginative as possible. The students can use Arkive as a resource for inspiration if they want to look at some real-life examples, and there is also an ‘inspiration slide’ at the end of this presentation which can be left on screen while the students design their flowers. © Richard Taylor

What is pollination? Pollination is how plants reproduce. Pollination happens when pollen grains (the male reproductive cells) are moved from the stamen (the male reproductive organ) to the stigma (the female reproductive organ) of another plant of the same species. After pollination has happened, the female parts of the plant are fertilised and seeds are produced. Once the seeds have been dispersed they will grow into a new plant. Start by asking the class if they know what is meant by the term ‘pollination’ and ‘pollinator’. Explain that pollination is the process by which plants reproduce. In order for pollination to happen, pollen must be transferred from the male part of the plant, the anther, to the female part (stigma) of another plant of the same species. Once the pollen has been transferred to the female part of another plant, it will begin to produce seeds. The seeds are then dispersed by the plant and will germinate and become a new plant. Once this plant has grown and begins to produce its own flowers, the process begins again.

Stamen The stamen is plant’s male reproductive organ. Stamens have two parts, the filament and the anther. The anther produces pollen and the filament supports the anther. The students will now learn about the different structures within the plant that are key players in the pollination process. Firstly, the stamen. The stamen is the plant’s male reproductive organ, and it is made up of two different parts – the filament and the anther. The role of the filament is to support the anther and position it into the best place possible. The anther produces pollen.

Pollen Pollen is the male reproductive cell of a plant. Pollen is extremely small and single grains can only be seen under a microscope – like in this picture. Pollen can be transported by wind, water or animals. Pollen is the male reproductive cell of a plant, which is produced by the anther. Pollen is often brightly coloured and although it is microscopic (tiny), it can be seen when it is grouped in large quantities on the surface of the anther. Tell the students to look at a flower closely next time they see some to try and see if they can tell where the pollen is. Single grains of pollen can only be seen under a microscope. Pollen is responsible for hay fever. Pollen can be transported from plant to plant by wind, water or animals.

Stigma The stigma is the female reproductive organ of a plant. For pollination to occur, pollen must be spread from the anther of one plant to the stigma of another. When pollen reaches the stigma it begins to grow. The stigma is the female reproductive organ of a plant. For pollination to occur, pollen must be transported from one plant to another. When pollen from another plant of the same species makes contact with the stigma, the pollen grains begin to grow.

The pollen produces a ‘pollen tube’ that grows towards the ovary. The ovary is the female reproductive organ, which is made up of single ovules. When the pollen the ovary, it fertilises it and the ovary develops into a seed. As pollen grows, it forms a ‘pollen tube’ which is a long tube that gradually grows towards the ovary. The tube eventually reaches the ovary at the base of the stigma.

Seed Once a seed is created, it will be distributed by wind, water or animals. Seeds contain all of the information needed to create a new plant. If a seed is dropped in a suitable location, it will begin to grow into a seedling. After the pollen reaches the ovary, the flower is fertilised and a seed or fruit will begin to grow. Seeds contain all of the information that they need to create a new plant. Seeds are distributed in the same way as pollen – wind, water or animal. If a seed is dropped in a suitable place, it will grow into a new plant. Image taken from: http://www.arkive.org/bushmans-river-cycad/encephalartos-trispinosus/image-G42454.html

Types of pollination All plant species have a main type of pollination that they use to reproduce. Some plants need to spread their pollen to a different plant of the same species to reproduce and these are called cross-pollinating. Other plants have flowers that contain both the male and female reproductive organs and can therefore create new plants themselves. These are called self-pollinating. Cross-pollinating plants can use three different transport systems to spread their pollen: wind, water or animal. There are four different types of pollination and every plant will use one or more type to spread its pollen. Some plants are cross-pollinating. This means that they rely on something else to spread their pollen. Other plants are self-pollinating and are able to spread pollen to other flowers on the same plant without needing something else to help them. Flowers can cross-pollinate using three different methods – wind, water or animal. All of these methods move the pollen from the anther of one flower to the stigma of another. Explain that even if a plant is self-pollinating it will still go through the same process to transport pollen from its anthers to its stigma but is able to do this itself rather than having to rely on something else to move the pollen for it. Explain that there are three different ways that plants can spread their pollen, but some plants can use more than one. These plants will have evolved to do this as using just one transport system can limit their success.

Animal pollination This pollination type happens when an animal visits a plant, usually to eat its nectar, and is covered in pollen while it eats. The animal will then continue its quest for more nectar and spreads the pollen that it has collected from one plant to the next. Plants only make nectar so that animals visit their flowers and collect their pollen – how clever! This exercise focuses on animal-influenced pollination. Animal pollination happens when an animal visits a plant to eat the nectar in its flower and is covered in pollen while it eats. The pollinator then travels to the next flower and eats the nectar from there, depositing some of the pollen from the previous plant. Ask the students if they know what nectar is. The main reason that most pollinators visit plants is to drink their nectar. Nectar is an extremely sugary liquid that is made by plants with the sole purpose of attracting pollinators. Producing nectar is a very sneaky way of spreading their pollen much further than they would be able to do on their own. Some animals are nectarivores which means they only eat nectar – no meat or plants.

Play the video to show the students how bees are covered in pollen while eating the nectar from a flower.

Animal pollinators Ask the students if they can name any other pollinators apart from bees (the images are animated so will only appear on the screen when a mouse is clicked. Explain that there are many different types of pollinator, not just bees! Although bees (1) are extremely important there are lots of other pollinators too – birds (2), bats (3), butterflies (4), beetles (5), flies (6) and moths (7) all have a part to play in pollination. Some plants are pollinated by many different animals, but others rely on a specific pollinator to spread their pollen. Every flower looks very different to each other – but why? This is because the flower of a plant is designed to attract a certain type of animal, or to attract as many animals as possible.

Design a flower for your pollinator How a flower looks can tell you a lot about its pollinator. Select a pollinator from the pollinator cards (this can be a surprise or students can choose specifically) and then read what its favourite flowers look like and the top facts on the card. Ask the students to design a flower for their pollinator using the suggested colours and shapes, and consider the needs of your pollinator. Don’t forget to show where the vital reproductive organs go – stamen (anther and filament) and stigma. The top facts can be used to add a bit of creativity to the flower. Here are some real flowers for inspiration (can be left onscreen while the students design their flowers, or printed and given to the students), or ask the students to use the Arkive website to find even more inspiration if you have the resources available. Once the students have finished designing their flower, ask them to look at the other pollinators that other students have to see whether they think their flower would be attractive to other animals too, and ask them to write which animals they think would be onto their worksheet. Images featured are (clockwise from top left): harlequin flower, common daisy, Mastigostyla torotoroensis, red pincushion protea, passion flower and rafflesia