Question

Consider the following, which of them is a response to a stimulus?

1. The closing of leaves of touch-me-not plant on touching.
2. The growth of a plant towards the light.

• A. Only 1
• B. Only 2
• C. Both 1 & 2
• D. None

Answer 1

The correct option is C Both 1 & 2

Movement in touch-me-not plant is a non-directional movement, which means that the response is independent of the direction of the stimulus. Growth towards light, gravity or water is directional movements i.e., either towards or away from the stimulus. Both these movements are a response to stimuli.