4. Light Independent Reaction Flashcards
the light independent reaction is also called the ____ _______
calvin cycle
where does thh Light independent reaction take place in?
the stroma of chloroplasts
what does the light independent reaction use?
uses CO2 and ribulose bisphosphate
what does the light independent cycle produce?
triose phosphate
what does the light independent factor need in order to work?
ATP and H+ ions
describe the first stage of the calvin cycle
- CO2 combines with ribulose bisphosphate, to form two molecules of glycerate-3-phosphate
- CO2 enters the cell through the stomata and diffuses into the stroma
- CO2 combines with ribulose bisphosphate
- this reaction is catalysed by rubisco
- this creates an unstable 6C compound which breaks down into two glycerate-3-phosphate molecules
what is ribulose bisphosphate
a five carbon compound molecule
describe the second stage of the calvin cycle
- ATP and NADPH are needed to transform glycerate-3-phosphate to two times triose phosphate
- ATP hydrolyses energy (from the LDR) so glycerate-3-phosphate can turn into triose phosphate
- H+ ions are also needed from NADPH (from the LDR)
- some triose-3-phosphate is used to make organic compounds and some continues in the Calvin cycle to regenerate ribulose bisphosphate
describe the third stage of the calvin cycle
- ribulose bisphosphate is regenerated
- 5/6 triose-3 phosphates regenerate ribulose bisphosphate
- regenerating ribulose bisphosphate uses the rest of the ATP from the LDR
how many cycles does the calvin cycle need to make RuBP?
three
how many turns of the calvin cycle to create one hexose sugar?
two
where is rubisco found?
stroma
what happens to the Calvin cycle if rubisco is affected?
- less CO2 binding with ribulose bisphosphate
- less production of glycerate-3-phosphate
How many molecules are needed to make RuBP?
5 molecules
How many cycles are needed to make one hexose sugar?
Six
