Chapter 39: Control Systems in Plants. Question. Do plants sense and respond to their environment ? Yes - By adjusting their pattern of growth and development. In Dark. In Light. Comment. Plants can’t “move” away from a stimulus, but can change their growth response.
Chapter 39:Control Systems in Plants
4. Abscisic Acid
Control shoot or root differentiation in tissue cultures.
Flowering (some species).
2. Circadian Rhythms
Statolith movement may be the receptor for the stimulus.
1. Rapid Leaf Movement
2. Sleep Movements
Ex: Bean Leaves Prayer Plant
Mimosa Rapid Leaf Movement
1. Short - Day Plants
2. Long - Day Plants
3. Day - Neutral Plants
Pr- responds to 660nm (red light).
Pfr - responds to 730nm (far red).
Very sensitive (1 minute difference).
Sets clocks for plant responses.
1. Developmental changes
2. Physiological changes