Which blue light receptors set the 24 hour activity cycle of a plant?

1. Two classes of receptor absorb blue light through a flavin based chromophore. 2. Cryptochromes set the 24 hour activity cycle of the plant, its circadian rhythm, using blue light cues. 3. Phototropins mediate phototropism along with stomatal opening and chloroplast movement. 4. Phytochromes respond to red and far red light rather than blue, so they are the trap for a reader who remembers only the word photoreceptor. _Source: OpenStax Biology (1st ed., CC BY 4.0), Ch 30 "Plant Form and Physiology", section 30.6 Plant Sensory Systems and Responses_