Primary 5 · Science · Cycles: Seed Dispersal & Germination
Cycles: Seed Dispersal & Germination questions for Primary 5 Science
9 questions to work through online, 2 of them written out the way the paper asks. Answer and you get the working straight away, then a score at the end. No sign-up, and you can retake it as often as you like.
- Inferring the method
- Designing a germination test
- Why boiled water is used
- What light does
- Why dispersal matters
- Naming a method
- Naming what a seed lives on
- Applying the ideas
| Seed | Mass | Outer surface | Floats? |
|---|---|---|---|
| J | very light | feathery hairs | ✗ |
| K | heavy | smooth and waxy | ✓ |
| L | light | covered in hooks | ✗ |
Same picture as the question above.
Answers and explanations for all 9 questions
Every answer with the reasoning behind it. Worth reading after you have tried the set — or on its own, if you are a parent marking it.
Based on the table above, how is seed K most likely dispersed?
Answer: by water
K floats and has a waxy surface that keeps water out. Those are the features of a seed carried by water.
Using the same table, which seed is most likely to be carried on an animal's fur?
Answer: L
Hooks catch in an animal's coat and are carried until they are brushed or rubbed off somewhere else. That is L.
In the set-ups above, which two pairs each test exactly one condition against set-up A?
Answer: A and B only
A is the set-up with everything. B removes only the water and C removes only the warmth, so each of those pairs isolates one condition. D is the one that removes the air.
In a germination experiment, seeds are placed under water that has been boiled and cooled. Why is the water boiled first?
Answer: to drive the air out of it, so the seeds get no air
Boiling drives dissolved air out of water. Seeds under it have water and warmth but no air, which is exactly the condition being removed.
Seeds germinate perfectly well in a dark cupboard. When does the seedling first need light?
Answer: once its food store runs out and its leaves must make food
A seed carries its own food, which is why it can germinate in the dark. Light becomes essential only when that store runs out and the leaves must take over.
Which two of these are advantages of seeds being dispersed far from the parent plant?
Answer: A and B only
Spreading out means seedlings are not shaded and starved by their own parent, and it lets the species reach ground it does not yet occupy.
A ripe pod dries in the sun until it suddenly bursts open, flinging its seeds several metres. What method of dispersal is this called? By ______ .
Answer: splitting
A pod that flings its own seeds is dispersal by splitting.
A seed germinating in a dark cupboard grows a root and a shoot without any light. What is it living on? The food ______ inside the seed.
Answer: store
It lives on the food store inside the seed until its leaves can make food.
Why do many plants that grow beside rivers have seeds that float?
Answer: The river carries floating seeds downstream to new ground.
A river is a free ride. A seed that floats is carried well away from its parent and deposited on a bank downstream, which is dispersal doing exactly its job.