Photosynthesis 2

• When a pair of electrons are released from photosystem 2, what occurs?

  They pass through the electron transport chain and are passed on to photosystem 1.This causes ATP to be generated.
• What is non-cyclic photophosphorylation?


  When light energy absorbed is used to generate ATP and the pair of electrons released by photosystem 2 don‘t return and instead reacts with H+ and NADP to produce reduced NADP.
• What is photolysis and why is it important?

  The splitting of water; a pair of electrons is produced that replaces the pair lost. Protons are produced which enhances the proton gradient.
• What is different about cyclic photophosphorylation?

  After the pair of electrons is lost from photosystem 1, they can return to photosystem 1 as a result of the chloroplast needing more ATP
• What does the movement of protons down a concentration gradient allow?

  It allows ATP synthase to generate ATP
• What enhances the proton gradient?

  Photolysis as it produces protons aswell as the production of reduced NADP, as this uses p
• What is chemiosmosis?

  Process by which ATP is generated as a result of protons leaving thylakoids
• What does CO2 react with in the first stage of the Calvin cycle and what is the catalyst?

  It reacts with RuBP and RubisCO catalyses the fixation of CO2
• What is formed from the fixation of CO2 and what happens to the product?

  2 molecules of GP are formed, but as they are unstable, they are reduced to 2 molecules of TP