Biology Unit 2: Light independent reactions

Main cycle in light independent reactions

Calvin Cycle

Does the Calvin cycle need light to function

no

First Phase of calvin cycle

Carbon Fixation

What happens in carbon fixation

3CO2 bonds to RuBP (ribulose 1,5-bisphosphate) which makes an unstable compound, this results in it immeditaly splitting to 3-phosphoglyceric acid

Second phase of Calvin cycle

Reduction

What happens in the reduction phase

ATP activates 3-phosphoglyceric acid cuz of its low energy, then it has enough to oxdize NADH, 6 molecules of glyceraldehyde 3-phosphate but only one goes to make glucose

Third phase of calvin cycle

Regeneration of ribulose

What happens in the third phase

the rest of the glyceraldehyde 3-phosphate are used to regenrate ribulose 1,5-bisphosphate, atp is ued to reform chemical bonds to make that happen

Why is glyceraldehyde 3-phosphate so special

1. used to make glucose and sucrose

2. regenerates ribulose 1,5-bisphosphate

3. starting substrate for cellulose

4. plant oils are derived from it

5. adding of an amino acid creates proteins

what does RuBisCO stand for

ribulose bisphosphate carboxylate

Major fact abour RuBisCO

most abundant enzyme on earth