energy for biological processes

• light independent stage

  1. carbon combines with RuBP
  2. rubisco catalyses the reaction to form a 6 carbon compound
  3. this compound is unstable so immediately separates to form a 3 carbon compound GP
  4. the hydrogen needed to convert GP to TP is used from the products of the light dependent stage, ATP and NADPH
  5. carbon from TP is used to make glucose, other carbs, lipids or amino acids
  6. the rest of the carbon is used to regenerate RuBP
• light dependent stage

  1. light energy absorbed by chlorophyll. electrons in chlorophyll are excited to a higher energy level
  2. electrons are lost from chlorophyll molecule
  3. electrons are passed between carriers in the electron transport chain
  4. energy released during the transfer of electrons in the ETC is used to generate ATP
  5. water molecules in the thylakoids are split into electrons H+ and oxygen (photolysis)
  6. electrons from water replace lost electrons from the chlorophyll
  7. NADP is reduced by addition of electrons down ETC
  8. oxygen from the splitting of water is lost as a waste product