1. Hormones and the Control of Plant Growth
- Plants respond to changes to their environment

2. Can you remember the 7 life processes?
Movement Respiration Sensitivity Nutrition Excretion Reproduction Growth

3. In what ways are plants sensitive to their surroundings?
Why is this important?

4. PLANTS ARE SENSITIVE Plants respond to the their surroundings
GEOTROPISM – response to gravity
HYDROTROPISM – response to water
PHOTOTROPISM – response to light
Tropisms are controlled by hormones known as Auxins
Growth of plants occur from the tips of the roots and shoots

5. PLANT ROOTS Roots always grow DOWN (positively geotropic)
Roots grow towards WATER (positively hydrotropic)
So that they can anchor the plant and absorb minerals/water
Roots grow away from LIGHT (negatively phototropic)

6. PLANT SHOOTS Shoots grow UP (negatively geotropic)
Shoots grow towards light (positively phototropic)
So that they can absorb light for photosynthesis

7. Germinating seeds What can you determine from the photos?

8. Tropisms – Britannica
Time lapse germination
Negative geotropism
Phototropism

9. AUXIN
Auxin affects how plants grow. It’s a growth hormone. A response happens due to an uneven distribution of the hormone

10. Auxin moves to the shaded side of the shoot and causes the cells there to elongate. This results in the shoot bending towards the light.

14. Describe and explain the growth of each plant

15. Why are the responses of shoots and roots so important in the life of plants?

16. YOU SAY WE PAY

17. Growth

18. Tropism

19. Germinate

20. Light

21. Shoot

22. Negative

23. Hydrotropic

24. Root

25. Down

26. Gravity

27. Photosynthesis

28. Geotropic

29. Hormone

30. Sensitivity

31. Positive

32. Water

33. Phototropic

34. Auxin

35. Up

36. Tips

37. Plant