Year 8 Science · Unit 1 · Lesson 15
Foundation Worksheet
Learning Goals
Fill the gap
Choose the correct word from the word bank. Two words will not be used.
A living system is made of many that with each other, so no part works on its own. If a plant’s are damaged, less and fewer minerals are taken in, and the may wilt. If an animal’s gas exchange is reduced, less reaches its body .
Put the breathing problem in order
The air sacs in a person’s lungs are damaged. Number the steps 1 (first) to 4 (last) to show how the problem spreads.
| Step (1–4) | What happens |
|---|---|
| Less oxygen passes from the air into the blood. | |
| Muscle cells release less energy, so the person tires quickly and feels short of breath. | |
| The gas-exchange surfaces in the lungs are damaged. | |
| The blood carries less oxygen to cells around the body. |
Sort it: plant or animal?
Each card is one link in the plant example (damaged roots) or the animal example (reduced gas exchange). Write each card in the correct box. Each box gets three cards.
Plant: damaged roots
Animal: reduced gas exchange
True or false? Fix the false ones
Circle T or F. If a statement is false, correct it on the line.
1. If a plant’s roots are damaged, only the roots are affected.
Correct it:
2. The effect of damage to one part may take days to show in the rest of the living thing.
Correct it:
3. Both plants and animals can show the wider effects of damage to one component.
Correct it:
4. Oxygen taken in by the lungs reaches body cells on its own, without the circulatory system.
Correct it:
Read the data
Scenario: moving tomato seedlings
A class planted 20 tomato seedlings from punnets into a garden bed. For Group A (10 seedlings), they lifted each seedling out with the ball of soil still around its roots. For Group B (10 seedlings), they pulled each one out and shook the soil off, which tore many of the fine roots. Both groups were watered the same. Each afternoon the class counted how many seedlings in each group had wilted.
| Day after planting | Group A: roots kept in soil | Group B: roots torn |
|---|---|---|
| Day 1 | 0 | 2 |
| Day 2 | 1 | 6 |
| Day 3 | 1 | 8 |
| Day 7 | 0 | 3 |
Source: sample class results.
1. On Day 3, how many seedlings had wilted in each group? How many more wilted in Group B than in Group A?
2. Only the roots of Group B were damaged, but it was the leaves that wilted. Complete the chain to explain why.
3. Group B’s roots were torn on the day of planting, but most of the wilting showed up on Days 2 and 3. By Day 7 fewer seedlings had wilted. Suggest a reason for each of these two observations.
4. Compare how damage to one component can affect a whole plant and a whole animal. Use damaged roots for the plant and reduced gas exchange for the animal. For each, trace the problem from the damaged part to the whole living thing, then say what the two examples have in common.
Fill the gap
components; interact; roots; water; leaves; oxygen; cells. Not used: bones, sunlight.
Put the breathing problem in order
Reading down the table as printed: 2, 4, 1, 3. (Air sacs damaged, less oxygen into the blood, blood carries less oxygen to cells, muscle cells release less energy and the person tires.)
Sort it: plant or animal?
Plant: the stem carries less water upward; fewer minerals reach the leaves; the leaves droop. Animal: less oxygen enters the blood; body cells get less oxygen; the body tires quickly.
True or false
1. False: less water and fewer minerals are taken in, so the stem and leaves are affected and the whole plant can wilt. 2. True. 3. True. 4. False: the circulatory system has to carry the oxygen from the lungs to body cells.
Read the data
1. Group A: 1; Group B: 8. So 8 − 1 = 7 more in Group B. [2 marks: 1 both readings, 1 difference]
2. Box 2: the roots take in less water (and fewer minerals). Box 3: the stem carries less water up to the leaves, so they lose water faster than it arrives. [2 marks: 1 per box]
3. Delay: the seedlings still had some water in their stems, leaves and the surrounding soil, so it took time for the shortage to reach the leaves. Fewer by Day 7: the seedlings grew new fine roots, so water intake rose again (accept any sensible reason). [2 marks: 1 each]
Show What You Know
4. Marking guide (points expected): 1 roots damaged, so less water and fewer minerals taken in; 1 stem and leaves receive less, so the plant wilts or grows poorly; 1 reduced gas exchange, so less oxygen enters the blood; 1 the circulatory system carries less oxygen to body cells, so the whole body is affected (tires, less energy); 1 in common: one damaged component disrupts what other parts receive, because the parts depend on each other. [5 marks]
Common error to watch for: stopping the chain at the damaged part (“the roots are damaged, so the roots don’t work”) instead of following it to the parts that depend on it.