Primary 6 · Science · Systems: Plant Parts & Transport
Systems: Plant Parts & Transport questions for Primary 6 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.
- Tracing a cut stem
- Reasoning about a ringed stem
- Which way each substance moves
- Combining with transpiration
- Combining with photosynthesis
- Why a plant wilts
- Naming the openings
- Naming the process
- Applying the ideas
| Plant | Leaves | Petroleum jelly on leaves | Water lost in 4 hours (ml) |
|---|---|---|---|
| A | 20 | none | 36 |
| B | 20 | on the undersides | 11 |
| C | 20 | on the upper surfaces | 31 |
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.
In the set-ups above, the leaves of both plants turned red. What does this show?
Answer: The tubes carrying water are not in the outer layer that was removed.
Ringing removes the outer tubes, and water still reached the leaves. So the water-carrying tubes must lie deeper in the stem.
A ring of bark is removed all the way round a tree trunk near the ground. Which part of the tree dies first?
Answer: the roots, because food can no longer reach them
The ring cuts the tubes carrying food down from the leaves. The leaves keep making food and stay green; the roots receive none and starve first.
Which two statements about transport in a plant are correct?
Answer: A and B only
Two separate systems: water up from the roots, food down from the leaves. Nothing edible is taken from the soil — only water and minerals.
Based on the table above, which conclusion is correct?
Answer: Most water is lost through the undersides of the leaves.
Blocking the undersides cut the loss from 36 ml to 11 ml; blocking the tops cut it only to 31 ml. Nearly all the openings must be underneath.
A plant is well watered but kept in a dark cupboard. Which process stops and which continues?
Answer: Photosynthesis stops but water is still taken up and lost.
Making food needs light and stops. Water still evaporates from the leaves and is still drawn up, so transport carries on regardless.
Which two situations would make a plant wilt?
Answer: A and B only
Wilting happens when water leaves faster than it arrives. Dry soil and damaged roots both cut the supply; shade and a bag cut the losses instead.
Leaves have thousands of tiny openings, mostly on the underside, through which water vapour and gases pass. What are these openings called?
Answer: stomata
The tiny openings in a leaf are the stomata.
Water evaporating from a plant's leaves is what pulls more water up the stem from the roots. What is this loss of water called?
Answer: transpiration
Water lost from the leaves as vapour is transpiration.
Why do many desert plants have leaves reduced to spines?
Answer: Less leaf surface means far less water is lost to the air.
In a desert, water is the limiting factor. Reducing the leaves cuts the surface water escapes from, and the plant photosynthesises in its stem instead.