Plants exhibit movements in response to environmental stimuli (light, gravity, water, chemicals) regulated by plant hormones; roots and shoots show contrasting responses to the same stimulus. Why is hydrotropism essential for plants?
Coordination in plants: tropisms and plant hormones
High importanceUsually 3 marks a paper · mostly case-based questions and MCQs · asked in 4 of the last papers
Notes are being written
The board questions below are real and complete — they come from the CBSE papers themselves. The written notes for this topic are still being prepared.
Board questions on this topic
8 from the CBSE papers we hold — the exact wording the board used.
Plants show movements in response to environmental stimuli regulated by plant hormones. What role does auxin play in the growth of plants?
Plants show movements in response to environmental stimuli regulated by plant hormones. Differentiate between movement shown by the sensitive plant and tropic movement by plants (Two points).
Plants show movements in response to environmental stimuli regulated by plant hormones. OR alternative for (c): How does movement of roots differ from that of shoots in response to gravity and light?
Plants have neither a nervous system nor muscles, even then they respond to stimuli. For example, the leaves of chhui-mui (touch-me-not) plant when touched begin to fold up and droop. (a) How is the information communicated in "touch-me-not" plants ? (b) What enables the plant cells to bring out the observable response ? (c) Differentiate the movement mentioned above from the movement of tendrils in a pea plant.
The plant hormone whose concentration stimulates the cells to grow longer on the side of the shoot which is away from light is :
- (a) Cytokinins
- (b) Gibberellins
- (c) Adrenaline
- (d) Auxins
How is the movement of leaves of a sensitive plant different from the downward movement of the roots?
Select from the following the correct statement about tropic movement in plants:
- (a) It is due to stimulus of touch and temperature.
- (b) It does not depend upon the direction of stimulus received.
- (c) It is observed only in roots and not in stems.
- (d) It is a growth related movement.