Primary 5 · Science · Systems: Plant Parts & Transport
Systems: Plant Parts & Transport questions for Primary 5 Science
10 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.
- Which tubes carry what
- Reasoning about a ringed stem
- What speeds up transpiration
- Reading results
- Where water is lost
- Why transport matters
- Reasoning about wilting
- Naming the process
- Naming what is transported
- Applying the ideas
| Plant | Leaves | Where kept | Water lost in 3 hours (ml) |
|---|---|---|---|
| A | 20 | windy spot | 31 |
| B | 20 | still air | 17 |
| C | 0 | windy spot | 2 |
Answers and explanations for all 10 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.
Which statement about the tubes in a plant stem is correct?
Answer: One set carries water upwards and another carries food in both directions.
Water travels up from the roots in one set of tubes. Food made in the leaves travels away in another set, reaching every part that needs it.
Some weeks after the set-up above was made, the leaves of tree B were still green but the roots had begun to die. Why?
Answer: Water still reached the leaves, but food could no longer reach the roots.
The ring removed the tubes that carry food downwards but not those carrying water up. The leaves are fed and stay green; the roots starve.
Which two of these would make a plant lose water faster?
Answer: A and B only
Heat and dry air help water evaporate from the leaves, and a breeze carries the vapour away so more can follow. Bagging or cooling the plant does the opposite.
Based on the table above, which pair should be compared to show that wind increases water loss?
Answer: A and B
A and B both have 20 leaves and differ only in the wind. The rise from 17 ml to 31 ml is therefore down to the wind alone.
Through which part of a plant is most water lost to the air?
Answer: the leaves
Leaves have a large surface and thousands of tiny openings for gases. Most of the water a plant draws up is lost through them.
Which two of these depend on water travelling up the stem?
Answer: A and B only
Water is a raw material for making food, and the pressure of water in the cells is what holds a soft plant up. A plant short of water both starves and wilts.
Why does a plant wilt on a very hot afternoon even though the soil is damp?
Answer: It is losing water from its leaves faster than the roots can take it up.
On a hot afternoon water leaves the leaves very fast. Even with damp soil the roots cannot supply it quickly enough, so the cells lose pressure and the plant droops.
Water is lost from a plant's leaves as vapour, which is what pulls more water up the stem. What is this process called?
Answer: transpiration
Water lost from the leaves as vapour is transpiration.
The tubes running from the leaves downwards carry the substance the leaves have made. What do they carry?
Answer: food
The tubes running down from the leaves carry food.
Why does a gardener trim off many of the leaves when moving a large shrub to a new spot?
Answer: Fewer leaves means less water lost while the damaged roots recover.
Moving a shrub damages its roots, so it cannot take up water as fast as before. Removing leaves cuts the losses until the roots have grown back.