Question

What is tropic movement? Give one example.

Answer 1

Tropic Movement:

1. Tropic movements, also known as tropism, are directional movements of bending or curvature that respond to an external stimulus. The direction of movement depends on the direction of the stimulus.
2. A tropic movement can either be positive or negative: towards the stimulus is said to be positive, and away from the stimulus is said to be negative.
3. Based on the nature of the stimulus, tropic movements can be of:

• Phototropism- Stimulus is light,
• Thigmotropism- Stimulus is touch,
• Gravitropism- Stimulus is gravity.

Example:

The ‘Touch Me Not Plant’ or Mimosa pudica is an example of negative tropic movement because it moves away from the stimulus once touched.