Light independent stage Flashcards
What are the light-independent reactions of photosynthesis commonly known as?
Calvin cycle
What complex organic molecules are produced from the light-independent reactions?
- Starch for storage
- Sucrose for transport
- Cellulose for making cell walls
Do the light-independent reactions require energy from light?
No, but they require ATP and reduced NADP from light-dependent reactions
What are the three main steps within the light-independent reactions?
- Carbon dioxide is combined with ribulose bisphosphate (RuBP)
- Glycerate 3-phosphate (GP) is reduced to glyceraldehyde 3-phosphate (GALP)
- RuBP is regenerated from GALP
What compound is formed when carbon dioxide combines with RuBP?
A 6-carbon (6C) compound
What is the role of the enzyme rubisco in the Calvin cycle?
It catalyzes the reaction between carbon dioxide and RuBP
What happens to the unstable 6-carbon compound formed in the Calvin cycle?
It splits into two molecules of glycerate 3-phosphate (GP)
What does it mean when carbon dioxide is ‘fixed’ in the Calvin cycle?
It has been removed from the external environment and incorporated into a molecule inside the plant cell
What is used to reduce glycerate 3-phosphate (GP) to glyceraldehyde 3-phosphate (GALP)?
Energy from ATP and hydrogen from reduced NADP
How many turns of the Calvin cycle are required to produce one molecule of glucose?
Six turns
What fraction of GALP is used to regenerate RuBP?
Five sixths
What are some biological molecules produced from the intermediate molecules of the Calvin cycle?
- Hexose sugars (e.g., glucose)
- Polysaccharides (e.g., starch, cellulose)
- Lipid molecules (e.g., triglycerides, phospholipids)
- Nucleic acids (DNA and RNA)
- Amino acids
Fill in the blank: The Calvin cycle produces ____________ and other important biological .
glucose
True or False: Glucose produced in the Calvin cycle can enter respiration reactions.
True
What are phosphates from the soil used for in the Calvin cycle?
To produce nucleic acids
What do nitrates form after combining with molecules from the Calvin cycle
Molecules of the Calvin cycle for amino acids to be produced
What types of molecules are primarily produced by photosynthesis?
- Amino acids
- Polysaccharides
- Lipids
- Nucleic acids
