Plants and light booklet
Plants and light booklet
- Unit 1: Living things
- Unit 2: Sound
- Unit 3: Materials in my world
- Unit 4: The Earth
- Unit 5: Humans
- Unit 6: Forces
This Topic is About...
- I will learn that plants need light and the right conditions to be healthy.
- I will learn that baby plants grow from seeds.
- I will talk about the importance of a fair test.
- I will look for patterns in results.
- I will make a conclusion from the results.
- I will make predictions and see if they are right.
You’re going to be a science explorer!
Key Words
- conditions
- germination
- seedling
- shoot
- wilt
Tap to Learn the Meanings!
- conditions: The things in the environment that affect how plants or animals live and grow.
- germination: When a seed starts to grow into a new plant.
- seedling: A young plant that has just grown from a seed.
- shoot: The new part of a plant that grows upward from the seed or stem.
- wilt: When a plant droops or bends because it doesn’t have enough water.
Great work! You’re learning key words about plant growth.
Plants need the right conditions
Plants need the right conditions to grow and be healthy.
The conditions they need are the right amount of:
- warmth
- water
- light
- air
A healthy plant has strong roots, stems and leaves.
An unhealthy plant may have yellow leaves. The plant may wilt.
What do baby plants need?
The flowers of a plant make seeds. Inside each seed is a very small root shoot and a very small stem shoot, both ready to grow. The seed also has a store of food for the baby plant to start growing.
We call this germination.
The root shoot grows first to get water. Then the leaf shoot grows.
The diagram shows what is inside a seed.
FUN QUESTIONS
1. The root shoot always grows downwards. Why is this?
Show answer
2. The stem shoot always grows upwards. Why is this?
Show answer
3. Look at what the children say. What do you think a plant needs to grow?
Show answer
Let’s Investigate!
Question: Can plants grow well in the dark?
You will need: Six similar young plants in the same sized pots and same soil, a light place, a box
Place three plants in the light and three plants in the dark.
What do you predict will happen?
Make sure you wash your hands after touching plants or soil.
Think about these questions:
- Why do the plants need to be similar?
- Why should the plants have the same soil and water?
Method:
- Observe the plants every day for five days.
- Water them if the soil begins to dry.
- Look for differences between the plants in the light and the plants in the dark.
- Record your observations in a table like this:
| Day | Observations |
|---|---|
| 1 | On Day One we observed no differences between the plants in the light and the plants in the dark. |
| 2 | |
| 3 | |
| 4 | |
| 5 |
Questions:
- Was your prediction right?
- How do you know this was a science enquiry?
- What kind of science enquiry was this?
Tap to See Example Answers
- Why plants must be similar: So the test is fair and differences are due only to light, not plant size or age.
- Why same soil and water: To keep all conditions the same except for light.
- Prediction (example): Plants in the light will grow well; plants in the dark will become pale and weak.
- Why this is a science enquiry: You observed, measured, compared and recorded changes over time.
- Type of enquiry: A comparative test because you compared two groups of plants under different conditions.
Great job! You used careful observations to investigate how light affects plant growth.
Why do seedling stems bend?
Baby plants are called seedlings.
FUN QUESTIONS
5. These seedlings growing near a window are four days old. Why are the stems bent?
Show answer
6. How could we change things so that the stems would grow upwards and straight?
Show answer
Let’s Investigate!
Question: How quickly will our plants grow?
You will need: plant seeds, soil, pots, ruler
Marcus and Zara grew a plant from a seed. They measured it at 9 am each day for nine days and recorded their results on the graph.
Look at the graph and answer the questions:
- How tall was the plant on day 1?
- How many days did it take for the plant to grow to 4 cm?
- On which days was the plant tallest?
- How tall might it be on day 9?
- What kind of science enquiry was this?
Tap to See Answers
- 1: On day 1, the plant was 1 cm tall.
- 2: It reached 4 cm on day 7.
- 3: The plant was tallest on days 7 and 8 (both 4 cm).
- 4: On day 9, it might still be around 4 cm if growth has slowed, or perhaps slightly taller.
- 5: This was an observing over time enquiry because they recorded changes over several days.
Great work! You interpreted a graph and used data to understand how plants grow over time.
Let’s Investigate!
Topic: Light and Plant Growth
You will need: some seedlings, two plant trays, soil, seeds, a ruler, a light place, a dark place
Method:
- Observe some seedlings. Look at their roots, stem and leaves. Draw them.
- Prepare two trays with soil. Sow ten seeds in each tray. Cover the seeds lightly with soil.
- Water the seeds so they do not dry out.
- Place one tray in a light place and the other in a dark place.
- Predict what you think will happen.
- Observe the trays over several days and measure seedling growth.
- Record the growth in charts like the one shown.
Questions:
- What do you observe about the way the seeds grow?
- What is the difference between the seeds in the light tray and the dark tray?
- Was your prediction correct?
- This was a science enquiry — could this be called a fair test?
- Was it also another type of enquiry?
How am I doing?
Explain to a friend the importance of a fair test.
Tap to See Example Answers
- What we observed: Seeds in the light grew short, green and healthy. Seeds in the dark grew tall and pale (trying to reach light).
- Differences: Light-grown seedlings had stronger stems and greener leaves; dark-grown seedlings were weak and yellowish.
- Prediction: Many predictions say the light seeds will grow better — this is usually correct.
- Was this a fair test? Yes — because both trays had the same number of seeds, same soil, same watering, and the only difference was light.
- Another type of enquiry: It was also an observing over time enquiry, because you measured growth over several days.
Excellent! You explored how light affects plant growth using a fair test and careful observation.