1. Cyclic and Non-cyclic
photophosphorylation
http://highered.mcgraw-
hill.com/sites/9834092339/student_view0/chapter8/cyclic_and_noncyclic_photophosp
horylation.html

2. Light independent reaction
(k) outline how the products of the light dependent stage are
used in the light independent stage (Calvin cycle) to produce
triose phosphate (TP) (reference should be made to ribulose
bisphosphate (RuBP), ribulose bisphosphate carboxylase
(rubisco) and glycerate 3-phosphate (GP), but no other
biochemical detail is required);
(l) explain the role of carbon dioxide in the light-independent
stage (Calvin cycle);
aka Dark Reaction aka Calvin Cycle aka Carbon Fixation Reaction

3. Photosynthetic
electron-transfer
reactions in
thylakoid
membrane
ATP NADPH
Carbon-fixation
reactions in
stroma
Sugars, amino
acids and fatty
acids
Water
Carbon
dioxide
Oxygen
+
Chloroplast
Cytosol
LDR
LIR

4. Word ladder
• Toad
• ----
• ----
• ----
• ----
• ----
• ----
• ----
• ----
• Frog
• Toad
• (street)
• (leaf through)
• (toward the back)
• (phobia)
• (achievement)
• (level or smooth)
• (banner)
• (whip)
• Frog
• Toad
• road
• read
• rear
• fear
• feat
• flat
• flag
• flog
• Frog

5. Phase one – carbon fixation
Ribulose bisphosphate
(RuBP)
(aka ribulose biphosphate)
(aka ribulose 1,5 bisphosphate)
Ribulose bisphosphate
carboxylase (RuBisCo)
Glycerate 3-
phosphate
(GP)
(aka 3-phosphoglycerate)
2X

6. Phase two – reduction (part one)
Glycerate 3-
phosphate
(GP)
(aka 3-phosphoglycerate)
1,3-
bisphosphoglycerate
(GP)

7. Triose
Phosphate (TP)
(aka glyceraldehyde-3-phosphate)
(aka G3P)
Phase two – reduction (part two)
1,3-
bisphosphoglycerate
(GP)

8. Regeneration Several steps
Triose
Phosphate (TP)
(aka glyceraldehyde-3-phosphate)
(aka G3P)
Ribulose 5-phosphate

9. Return to the start
Ribulose bisphosphate
(RuBP)
(aka ribulose biphosphate)
(aka ribulose 1,5 bisphosphate)
Ribulose 5-phosphate

10. Glycerate 3-phosphate
2. Reduction
1. Carbon
fixation
6x Triose phosphate
1x Triose
phosphate
5x Triose
phosphate
3. RuBP is
regenerated
from triose
phosphate
Calvin Cycle/LIR
Glucose

12. The role of Carbon Dioxide

13. Useful Animation
• http://www.science.smith.edu/departments/
Biology/Bio231/calvin.html
• http://highered.mcgraw-
hill.com/sites/007337797x/student_view0/ch
apter7/animation_quiz_-
_how_the_calvin_cycle_works.html

14. Summary test…
• The light independent reaction is also
known as the (1) cycle. In the process,
carbon dioxide combines with a 5-
carbon compound called (2) to form a 6-
carbon intermediate that immediately
splits into 2 molecules of (3). By the
addition of (4) and (5) formed in the (6)
reaction, each of these molecules is
converted into a (7) molecule. These
combine to form a (8) sugar that can
then be made into starch by a process
called (9).

15. Glycerate 3-phosphate
2. Reduction
1. Carbon
fixation
6x Triose phosphate
1x Triose
phosphate
5x Triose
phosphate
3. RuBP is
regenerated
from triose
phosphate
Calvin Cycle/LIR
Glucose
Can be used to make
carbohydrates, lipids
or amino acids