1. Plant Responses

2. All living organisms are sensitive to changes in
their surroundings.
Plants are sensitive to light, moisture and gravity.
The response to light is called ______________.
The response to gravity is called ___________.
The response to moisture is called ___________.

3. All living organisms are sensitive to changes in
their surroundings.
Plants are sensitive to light, moisture and gravity.
The response to light is called phototropism.
The response to gravity is called ___________.
The response to moisture is called ___________.

4. All living organisms are sensitive to changes in
their surroundings.
Plants are sensitive to light, moisture and gravity.
The response to light is called phototropism.
The response to gravity is called geotropism.
The response to moisture is called ___________.

5. All living organisms are sensitive to changes in
their surroundings.
Plants are sensitive to light, moisture and gravity.
The response to light is called phototropism.
The response to gravity is called geotropism.
The response to moisture is called hydrotropism.

6. •Shoots grow upwards - towards light and against the force of
gravity.
•Roots grow downwards – towards moisture and in the direction of
the force of gravity.

7. Phototropism and Auxin

10. Geotropism and Auxin

11. Geotropism and Auxin

12. Commercial Uses of Hormones

13. Commercial Uses of Hormones
1. Rooting powder contains auxin.
It is applied to cuttings to stimulate the growth of roots.
Large numbers of plants can be produced quickly, so more money can
be made.

14. Commercial Uses of Hormones
1. Rooting powder contains auxin.
It is applied to cuttings to stimulate the growth of roots.
Large numbers of plants can be produced quickly, so more money can
be made.
2. Hormones control fruit ripening.
Producers use chemicals to slow down the ripening of fruits, such as
bananas, during transport.
Just before sale, ripening can then be speeded up using different
chemicals and a warmer temperature in the storerooms.

15. Commercial Uses of Hormones
1. Rooting powder contains auxin.
It is applied to cuttings to stimulate the growth of roots.
Large numbers of plants can be produced quickly, so more money can
be made.
2. Hormones control fruit ripening.
Producers use chemicals to slow down the ripening of fruits, such as
bananas, during transport.
Just before sale, ripening can then be speeded up using different
chemicals and a warmer temperature in the storerooms.
3. Weedkillers contain synthetic hormones that stimulate the plants to
grow very rapidly.
Their normal growth patterns are disrupted.
They become tall and spindly, and eventually die.