Light dependent reaction

Annotations:

• Oxidation loss of electrons  Reduction gain of electrons

1. Chlorophyll molecule absorbs light Energy
   1. Boosts energy of of a pair of electrons -they are in an exited state
      1. Electrons leave the chlorophyll molecule are taken up by an electron carrier
         1. Chlorophyll molecules has been oxidised, the electron carrier reduced
            1. The electrons are passed along a number of electron carriers in a series if oxidation-reduction reactions
               1. Electron carrier form a transfer chain in the membrane of the thylakoids
                  1. Each new carrier- lower energy this lost energy is used to combine inorganic phosphate molecule with an ADP to make ATP
                     1. ATP + H2O => ADP + Pi + energy

1. Lost Chlorophyll electrons are replaced
   1. Provided from water molecules that are split using light energy
      1. 2H2O=> 4H+ + 4e- + O2
         1. H+ ions are taken up by a electron carrier called NADP And becomes reduced to NADPH which then enters the light- independent reaction
            1. NADPH is important because it is a further potential source of chemical energy
         2. O2 byproduct used in respiration or diffuses out of the leaf