Roles of Pfr

• why can Pfr do all this shit?

  Its a TF
• 1. seed germination

  • its underground so theres not much light (to convert Pr -> Pfr)
  • soooo has high Pr
  • abscence of Pfr/ high levels of Pr causes seed germination
• 2. stem elongation

  • seedlings underground, lacks light, so has high Pr
  • Pr inhibits lateral growth & straightens stem
• 3. leaf expansion

  • seedlings has rolled leaves when their underground
  • to prevent energy loss
  • when they grow into sunlight, Pr -> Pfr
  • Pfr promotes leaf development/unrolling, when their's sufficient red light to convert Pr -> Pfr
• 4. chlorophyll formation

  • seedlings are white (no chlorophyll) & high Pr, as they were unndergound
  • but when they grow towards sunlight
  • Pr -> Pfr
  • which causes chlorophyll production
  • so seedlings can photosynthesise