1. What is phototropism and how does it help plants survive?
Starter:
The circle on the board represents the Earth.
Come up and draw a plant growing somewhere on the Earth.

2. Learning Outcomes
Explain how phototropism increases a plant’s chances of survival
Describe how plant shoots grow towards a light source
H: explain phototropism in terms of the redistribution of auxin in shoot tips

3. Call my Bluff
Phototropism –

4. Call my Bluff
Phototropism – the movement of a plant in response to light.
Phototropism – a professional picture of a plant.
Phototropism – A 17 sided shape, mimicked in nature by some seeds.

5. Key words
Tropism: responding to a stimulus by growing towards it or away from it.
Phototropism: the movement of a plant in response to light.
Auxins: Plant hormones

6. MRS GREN
What are the 7 signs of life?

7. Sensitivity

8. Think – Pair – Share
How are animals sensitive to the environment? How do they respond to the environment?

9. Animal Sensitivity

10. Plants

11. Plants are sensitive to..
Light
Gravity
Moisture
What has happened to this plant? How is that an advantage?

12. Video time
Phototropism

13. Direction of growth The shoot grows: Towards the light
Away from gravity
The root grows:
Away from light
Towards gravity
Towards moisture

14. Phototropism animation

15. Auxins are hormones made by the shoot tip, that control how plants respond to sunlight.
They make the cells on one side of the plant grow longer so that the shoot bends towards the light.
Key word:
Elongation

16. In small groups
On A3 paper draw what you think a stem would look like in the following situations.
With light to the right.
With light to the left
With light up above.
With light to the right by no stem tip.

17. Task
Complete the worksheet showing the directions plants move and the position of auxins.

18. Plenary
Make a revision card with the key points about phototropism.

19. We are going to set up an experiment today to look at the way position of light affects the direction of growth of plants.
Method
Collect 3 petri dishes and line them with growing medium.
Water the growing medium.
Place 6 seeds in each dish.
Collect a coloured lamp and set it up on the bench.
Place the seeds 20cm away from the lamp and place a box over the experiment.

20. Questions
What are we changing about the experiment?
(What are we testing?)
2. What are we going to measure and take results of?
3. What do we want to keep the same so we don’t affect the results?
4. What do you think will happen in the experiment?