Light-independent Reactions Flashcards
Where are the ATP and Hydrogen from, and what are they used for?
From photolysis, and they are used to fix carbon dioxide to make organic molecules.
Where does the Calvin cycle occur?
Within the stroma of the chloroplast.
What is needed for the Calvin cycle to occur?
CO2, ATP, NADPH, and the 5-C RuBP which is recycled.
What is produced from the Calvin cycle?
“Baby” glucose (glycerate 3-phosphate).
Describe carbon fixation.
The carbon dioxide combines with ribulose biphosphate in a carboxylation reaction.
What is carbon fixation catalyzed by?
The ensyme ribulose biphosphate carboxylase (rubisco).
Why are there a lot of ribulose biphosphate carboxylase in the stroma of the chloroplast?
Because the process is slow, and because it’s really important.
What happens with the product of the reaction with rubisco?
A six-carbon compound is produced, which IMMEDIATELY splits to form two molecules of glycerate 3-Phosphate.
What is G3P and where does it come from?
Gycerate 3-phosphate, an organic acid. It comes from the carbon fixation reaction.
What becomes of glycerate 3-phosphate and how does it happen?
It si converted into a carbohydrate (triose phosphate) by a reduction reaction. This happens because NADPH provides the hydrogen. Energy is supplied by ATP.
What happens in Phase 1?
Carbon fixation, splitting, and phosphorylation.
What happens in Phase 2?
Reduction, by adding H+ and e- from (6) NADPH and (6) inorganic phosphate.
What happens in Phase 3?
Release of one molecule of G3P (baby glucose).
What happens in Phase 4?
Regeneration, where five 3-c molecules rearrange to make 3 RuBP.
What is triose phosphate used for?
To regenerate RuBP. (Using ATP)
How many molecules of triose phosphate are converted into how many molecules of RuBP?
Five molecules of triose phosphate are converted by a series of reactions into three molecules of RuBP. (Uses ATP)
Of every 6 molecules of triose phosphate formed in the light-independent reactions, how many must be converted to RuBP?
5 must be converted into RuBP.
How is glucose phosphate produced?
When two triose phosphates are linked together.
What is starch in the chloroplast and where is it found?
Starch is the storage form of carbohydrates in plants, and it’s formed in the STROMA by condensation of many molecuels of glucose phosphate.
