2. Light and plants

Plants use light energy for heating and photosynthesis, but also as a synchronization signal to trigger certain physiological processes (photomorphogenesis) such as flowering, foliage or stem development, or germination.

From a physiological point of view, photosensitive proteins called "photoreceptors" perform the functions of photosynthesis and photomorphogenesis. There are two types of photoreceptor: photosynthetic pigments, whose role is to capture light energy for photosynthesis, and photosensory receptors, which trigger photomorphogenesis.