The document discusses different types of movements in plants. There are two main types of movements: tropic movements and nastic movements. Tropic movements are directional movements towards or away from a stimulus, and include phototropism (response to light), geotropism (response to gravity), hydrotropism (response to water), chemotropism (response to chemicals), and haptotropism (response to touch). Nastic movements are plant movements that are not in response to an external stimulus.

1. ATHIRA LEKSHMI V.S
18121351005
NATURAL SCIENCE

3. The orientation of the plant part in response to external or
internal stimuli like light, water, touch, gravity etc. are
called plant movements.

4. Plant shows various types of movements.
Movements in plants are of two main types.
They are ;
1. Tropic movements
2. Nastic movements

5. Tropic movements are directional movements towards or
away from stimulus. Tropic movements in plants are,
1. Phototropism
2. Geotropism
3. Hydrotropism
4. Chemotropism
5. Haptotropism

6. Phototropism is the movement of plants
in response to light
Bending of
plants towards
light

7. If movement is towards light, it is called positive
phototropism.
Eg: bending of shoot towards light
If movement is against light, it is called negative
phototropism
Eg: Bending of root away from light.

8. .
It is the movement of plants in response to gravity.

9. If movement is towards gravity it is called positive geotropism.
Eg: Downward growth of root.
If movement is away from gravity it is called negative
geotropism. Eg: Upward growth of shoot.

10. Hydrotropism is the movement of plants in
response to water.

11. The plant roots always move towards water hence shows
positive hydrotropism.
The growth of plant shoot against the direction of water in the
soil is an example of negative hydrotropism.

12. It is the movement of plants in response to
chemical stimuli.
Growth of pollen tube towards ovule is an
example for chemotropism. Pollen tube

13. Haptotropism is the movement of plants in response to
touch.
Climbers grow towards and around a support.

14. If the direction of plant movement is not in accordance
with the stimulus, it is called nastic movement.

15. Plants exhibit movements in response to various
stimuli. Light, gravity, water, touch, chemicals etc.,
are various stimuli which cause movements in
plants.