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Study Guides
Control Systems in Plants
Plants, like animals, need to respond to changes in their environment. They need to know when conditions are right for growing, reproducing, and under what conditions to stop growing.
Hormones and other chemical messengers control these processes. Hormones signal for genes to be turned on and off in response to different cues, such as the amount of time a plant spends in the dark before light strikes it.
Scientists have performed many experiments on Earth and even in outer space to try to understand just how plants do what they do. In this Lesson, we’ll explore the control systems in plants.
