- Students will be able to:
- Locate stamens in different types of flowers.
- Collect pollen samples from stamens and mount them.
- Explain the importance of pollen in the process of fertilisation and seed production.
What You Will Need:
- A selection of flowers. (Note, pollen can be collected from larger flowers without picking them. However, small flowers need careful, close-up handling, which is best done on a table using tweezers.)
- Black paper or card.
- Magnifying glasses.
- Plastic tweezers can be helpful in removing flower parts to access stamens.
- Microscopes (optional).
- Microscope slides (optional).
What to do
- Collect a variety of flowers that are in fresh, full bloom. They need to be fully open and not too old. Several students should be able to use a single large flower, but smaller flowers may only have enough pollen for one student.
Examples of flowers for pollen sampling.
- Back indoors, inspect a flower closely to locate its stamens. Sometimes you may need to look inside the flower to locate them. These are the structures that produce the pollen.
- Gently dab the sticky side of a 3 cm length of sellotape onto the stamens. Pollen should stick to it. Make sure you get a good amount of pollen, but try not to pull the stamens off.
Using sellotape to take a sample of pollen from a flower's stamens.
- Stick the sample on a black piece of paper and label it.
Pollen samples from two different types of flowers.
- Repeat for other flowers.
- View the grains through a magnifying glass.
- If you have a microscope, then tape some samples to microscope slides to view them. Magnifications of x40 and x100 are best.
Pollen sample sellotaped to a microscope slide.
Questions and discussion
- Describe where stamens can be found in different types of flowers.
- For different flower types are there differences in the amount, colour, shape and size of pollen grains? Describe them.
- How would an insect carry pollen from flower to flower? Do they do this on purpose?
- What is the purpose of pollen and why is it important?
- If pollen could not get from flower to flower, what would happen?
- Why are pollination 'vectors' (e.g. honey bees, birds like tūī that visit flowers, and wind) important?
Find out more about pollen, for example:
- its different shapes and forms
- how it sticks to animals
- how it gets transported by the wind
- why it is found in honey.
Picture credits: Thumbnail image (CC BY-SA Josef Reischig).