ARTICLES
Lesson / Activity: Seeds that Fly (continued)
Teacher background This lesson begins with children putting different seeds and fruits into water – consider starting this activity
outside.
information
In this lesson, children are asked to examine a range of seeds and fruits that contain seeds, to predict which
ones would be dispersed by wind, water or both. They devise their own ad hoc methods for checking their
predictions.
Teachers should allow time for students to test their initial ideas and pose new questions of their own.
Flowering plants have adapted a range of different methods for seed dispersal, including seeds that can be
dispersed by the wind or water, or some mixture of both. Seeds that are dispersed by the wind are usually
light and small in size. They may have some sort of ‘wing’ or aerofoil that slows their descent by generating lift
or providing extra drag. Others have fine hairs that again produce drag. These adaptations allow these seeds
to be blown away from the parent plant. As a consequence there is less competition between adult plants
and seedlings, increasing the likelihood that the seed will germinate and therefore the species chances of
survival.
Flowering plants that disperse seeds by water often have fruits that float (ie less dense than water). The
seeds themselves may not float however: once the fruit floats away from the parent plant and begins to rot,
the seeds inside sink through the water and into the soil where they germinate.
For information about the difference between seeds and nuts, see: https://www.woodlandtrust.org.uk/
blog/2017/07/difference-between-nuts-and-seeds/
Equipment
• Seeds and fruits of different types, including those dispersed by wind/not dispersed by wind eg
• maple seed
• plane tree seed
• dandelion head
• grass seed heads
• avocado fruit
• coconut
• apricot
• peach
• apple
• sunflower seeds (in casing – ie seeds rather than just kernel)
• Large plastic container of water (single Kinder water tray OR 2 or 3 large plastic tubs)
• Knife and chopping board
• 2 Electric pedestal fans
• 2 Jewellery scales
Risk Assessment
• Consider moving this lesson outside if floor surface is likely to get slippery when wet.
• Ensure electric fans are kept well away from water to prevent electrocution.
• Check with parents for food allergies.
• Teachers to be responsible for cutting any fruits.
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SCIENCE EDUCATIONAL NEWS VOL 67 NO 1