Photosynthesis
Photosystem –
Non-cyclic Electron Flow in Light Dependent Reactions
1. _________________ excites photosystem (II).
2. H2O splits into _______________________________
 In the thylakoid
 O2 is released by the plant
 2H+ help create a concentration gradient
 2 electrons ar passed through electron transport
3. Electrons go to _________________________ then
through b6-f complex to ______________________. The b6-f complex pumps H+ from the stroma into
the thylakoid to generate a ___________________________________.
4. ________________________ in the PC get excited by photon hitting photosystem II.
5. Electrons from PC get passed to _________________________________ and through NADP reductase
enzyme which ___________________ NADP to NADPH.
6. Build-up of __________in the ________________ causes a concentration gradient (chemiosmosis)
where H+ will go through ATP synthase to produce ATP from ADP and PI
Photophosphorylation –
Net Result of Light Dependent Reactions:
Cyclic Electron Flow
Light independent reactions require _______________________________________ - therefore more ATP
needs to be made than NADPH….
Cyclic photophosphorylation can occur to produce extra ATP.
Electrons can flow in a cycle allowing for more ________________________________.
Once electrons are accepted by Fd, they are cycled back _______________________________ and cause
additional H+ to cross the membrane. With additional H+ on the thylakoid side of the membrane, ATP synthase
makes more ATP.
NADPH is not made because electrons were not passed to NADP reductase.
The Calvin Cycle
The Calvin Cycle
 Occurs in the ______________________ of the chloroplast
 Takes 3 CO2 and produces _________________________________________________________
 No ___________________________ is required for the Calvin Cycle to take place and it is therefore
called __________________________________________.
Steps in the Calvin Cycle
1) Fixation of carbon dioxide
3CO2 combines with ribulose bisphosphate (RuBP) to make 2 3- phosphogylcerate molecules
2) Reduction of 3-phosphogylerate into glyceraldehyde-3-phosphate (G3P)
uses ATP and NADPH
product = G3P
3) Regeneration of RuBP from G3P
Uses ATP
The Fate of G3P
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



Net Equation for Calvin Cycle