The Calvin cycle

3 main steps

1. Carbon fixation

2. reduction (the gaining of electrons)

3. Regeneration

Stepp 1:

Carbon Fixation:

• cycle begins with a 5-C molecule called ribulose bisphosphate (RuBP)

• An enzyme, RuBisCo, attaches a CO2 molecules to the RuBP

• The resulting 6-C molecule immediately breaks down into two 3-C molecules called GP or G3P

Step 2:

Reduction;

Reduction= the addition of electrons

NADPH transfers electrons and H= ions to the 3-C molecule

ATP is hydrolyzed to power the process

One of the 3-C molecules leave the cycle, the other continues on

Step 3

Regeneration of RuBP

the remaining 3-C molecules are rearranged to re-create the three 5-C RuBP that started the process

ATP is needed to power the regeneration