Coordination in Plants.

Plant responses and movements

Plants do not possess a nervous system like animals. Instead, they rely on chemical coordination to respond to external stimuli. As a result, their responses are generally slower compared to animals.

Although plants do not move from one place to another, they exhibit movement of organs and growth movements in response to external factors. These movements are driven by sensitivity and response to stimuli.

Types of movements in plants

Plants and plant-like organisms exhibit three main types of movements:

1. Tactic movement:
   • A type of movement where the whole organism or part of it moves towards or away from a stimulus.
   • Example: Movement of algae towards light (positive phototasis).
2. Nastic movement:
   • Movement that is not dependent on the direction of the stimulus, but rather on the intensity of the stimulus.
   • Example: Closing of Mimosa pudica (touch-me-not) leaves when touched.
3. Tropic movement:
   • Movement of plant parts towards or away from a directional stimulus.
   • Example: Phototropism (movement of plant shoots towards light) and Geotropism (movement of roots towards gravity).