Developmental processes

• List the developmental processes controlled by phytocromes

  1. Seed germination
  2. Flowering
  3. Stem elongation
  4. Leaf expansion
  5. Chlorophyll formation
• Describe seed germination

  . Germination was more effective when seeds were closer to surface

  . But seeds that were buried deep in ground did not germinate

  . Red light triggered germination

  . Far red light inhibited germination

  . Reversible
• Describe flowering

  . Flower at cetain times of the year

  . Determined by photoperiod

  . In winter theres lots of time for Pfr -> Pr

  . In summer theres lots of time for Pr -> Pfr
• Describe stem elongation

  Emerging seedling has lot of Pr