#Id: 7530
#Unit 6. System Physiology – Plant
Phototropism Is Mediated by the Lateral Redistribution of Auxin
In response to a directional light stimulus, the auxin produced at the tip, instead of being transported basipetally, is transported laterally toward the shaded side. Two flavoproteins, phototropins 1 and 2, are the photoreceptors for the blue-light signaling pathway that induces phototropic bending in Arabidopsis