What's Happening?
But dandelions are not the only plant that sends seeds away. Some seeds stick to a dog's fur. Some seeds float on water. Some seeds are inside yummy berries that birds eat!
What Scientists Know
Plants cannot walk or run. They stay in one spot their whole life! But their seeds need to travel to new places. This is called seed dispersal (that means seeds spreading out to new spots).
Why do seeds need to move? If all the seeds fell right under the parent plant, they would be too crowded. They would not get enough sunlight, water, or space. Seeds travel so that new plants have room to grow!
Seeds Travel by Wind
Seeds Travel by Animals
Let's Try It!
Scientists learn by making models. A model is something you build to show how something works. Let's make a model of seed dispersal!
What you need:
- 🟡 Small cotton balls (these are your "seeds")
- 📄 A piece of paper
- ✂️ Tape and thin paper strips
- 💨 A fan or your own breath
When you try this, you are thinking like a scientist! Scientists build models to understand how things work in nature. Your cotton ball model shows how wind moves seeds.
What We Discovered
When we tried the model, we saw something important. Seeds with fluffy parts went much farther than seeds without them. This is just like what happens in nature!
The shape of a seed helps it travel. Dandelion seeds have tiny parachutes. Maple seeds have wings that spin like helicopters. Coconuts are big and can float on water. Burr seeds have tiny hooks that grab onto fur or clothes.
The way a seed is shaped tells us how it will travel. This is because the shape of something helps it do its job.
Do You See the Pattern?
Let's look for a pattern! A pattern is when the same thing happens again and again.
Look at the seeds we learned about. Fluffy seeds travel by wind. Yummy fruit seeds travel by animals eating them. Hooked seeds travel by sticking to animals. Each seed's shape matches how it travels.
This pattern shows up in other places too. Not just with seeds!
| THING | SHAPE | WHAT IT DOES |
|---|---|---|
| 🌼 Dandelion seed | Fluffy like a parachute | Floats in the wind |
| 🦆 Duck's feet | Flat and wide like paddles | Helps the duck swim |
| 🦅 Eagle's claws | Curved and sharp like hooks | Grabs and holds food |
| 🌵 Cactus spines | Thin and pointy | Keeps animals away |
Do you see the pattern? The shape of something helps it do its job. Scientists call this structure and function. Structure means shape. Function means job.
Seeds and People
People use science to solve problems! Farmers need to plant seeds in the right places. They learned from watching how seeds spread in nature.
Did you know that the hook-and-loop fastener (you might call it Velcro) was invented because of seeds? A man went for a walk with his dog. When they came home, burr seeds were stuck all over the dog's fur! He looked at the tiny hooks on the burrs with a microscope. Then he made a new invention that sticks together the same way!
You can be an inventor too! Think about this: Can you design a seed that travels really far in the wind? Try cutting paper into different shapes and dropping them from up high. Which shape floats the longest? You are using the engineering design process — just like real engineers!
Key Vocabulary
- Seed — The small part of a plant that can grow into a new plant.
- Seed Dispersal — When seeds spread out and travel to new places away from the parent plant.
- Pollination — When pollen moves from one flower to another so the plant can make seeds. Bees and butterflies help with this!
- Model — Something you build or draw to show how something works in real life.
- Structure — The shape or parts of something.