calvin cycle Flashcards
explain the electron transport chain
- PS I can function independently of PSII
Instead of reducing NADP+, the electrons are moved back to PQ - PQ again uses the electrons energy to transport H+ inside the Thylakoid Lumen as it moves to the cytochrome complex
- This eventually creates more ATP than NADPH to satisfy the increased demand for ATP in the Calvin Cycle, and other reactions.
what is the calvin cycle called sometimes
the dark cycle
where does the calvin cycle occure
the stroma of the chloroplast
what are the 3 stages of the calvin cycle
- Carbon Fixation
- Reduction Reactions
- RuBP Regeneration
what happens when there is a reduction of CO2 to glucose
there are small uphill steps
- Each catalyzed by a specific enzyme
- Using energy stored in ATP and NADPH
glucose contains a lot of chemical energy meaning…
it is highly reduced
CO2 has very little chemical energy
meaning…
it is fully oxidized
what happens when CO2 is added to a 5-carbon molecule
6-carbon molecule is immediately split in half
what happens when Energy is added (ATP and NADPH)
2 G3P are formed (3 carbons)
What is the problem with this
We have nothing less to continue the cycle
What does 3 molecules of CO2 convert 3 molecules of RuBP in
3 - 6 carbon molecules
What enzyme catalyzes the reaction in carbon fixation
RuBisCo
What does the 3 6-carbon molecules break down with
Water
What does carbon and water break down into
3-PGA
What is the RuBisCo enzyme
Fixes carbon from air
- makes life out of air therefore it is the most important enzyme
- most abundant enzyme in the world
- 6kg/person
Explain the reduction reaction
- the six molecules of 3-PGA are phosphorylated by six molecules of ATP to make 1,3-PGA
- 6 molecules of 1,3-PGA are reduced into 6 molecules of NADPH to make 6 G3P
How many G3P are used to make glucose
One
What will happen to the other 5 molecules of G3P in the reduction reaction
G3P will move to the final stage
What is RuBP regeneration
- 5 G3P will be phosphorlated by 3 ATP and 2 Water
- these are added to make 3 RuBP so the cycle can continue
3 turns of Calvin cycle will make
1 G3P
6 turns of Calvin cycle makes
Glucose
Where will the left over ATP go
To other functions in the cell