Cryptochromes control photomorphogenesis in response to:
Cryptochromes control photomorphogenesis in response to:
Select an option to attempt
Correct Answer: Option D
Explanation
Cryptochromes: photoreceptors and their light absorption:Cryptochromes are plant (and animal) photoreceptors that absorb:• Blue light (400–500 nm), particularly around 450 nm• UV-A light (~315–400 nm)Plant cryptochrome functions:• CRY1 and CRY2 in Arabidopsis:- Inhibit hypocotyl elongation in blue light (photomorphogenesis)- Promote flowering (circadian clock interaction)- Regulate anthocyanin accumulation- Entrain circadian rhythmsDistinction from other photoreceptors:• Phytochromes: absorb red (660 nm) and far-red (730 nm) light.• Phototropins: absorb blue/UV-A, regulate phototropism and stomatal opening.• UVR8: absorbs UV-B light.Cryptochromes contain FAD (flavin adenine dinucleotide) as a chromophore.Answer: Cryptochromes absorb blue light (400–500 nm) and UV-A; regulate photomorphogenesis and circadian rhythms.