Plants tactic towards light, how?

[aychamo]

Hey guys;

I have a question, how is it that plants are able to "move" towards light? How do they bend towards it, etc?

[iansmith]

It is believed that a yellow pigment related to riboflavin acts as a photoreceptor for light.
a. Following reception, plant hormone auxin migrates from bright side to shady side of a stem.
b. How reception of stimulus couples to production of auxin is not yet known.
4. Auxin is also involved in gravitropism, apical dominance, and root and seed development.

http://www.sirinet.net/~jgjohnso/apbio38.html

http://www.pubmedcentral.gov/articlerender.fcgi?tool=pmcentrez&artid=150607