Please Do Now: 1) What role does sunlight play in the electron transport chain? 2) Where do the electrons that are passed through the electron transport chain come from?

 Do Now  Video Clip  Light Independent Reactions Notes  Data Analysis  Calvin Cycle Worksheet

 Sunlight in  Chemical Energy out ◦ (ATP and NADPH)

Chemical Energy

 Uses the ATP from the light reactions  Takes place is the stroma of the chloroplast (outside the thylakoid, inside the chloroplast).  3 steps: 1. carbon fixation, 2. reduction 3. regeneration ALSO KNOWN AS DARK REACTIONS

 Carbon fixation ◦ The enzyme RuBisCo combines the 5- Carbon compound RuBP with carbon dioxide (CO 2 ) to make an unstable 6 carbon compound

 Reduction: The unstable 6 carbon compound is split apart and reduced into 2 molecules with 3 Carbons, called G3P ◦ Requires ATP and NADPH

Regeneration: A large array of enzymes rearrange 5 G3P molecules into 3 RuBP molecules, which start off the Calvin cycle  ATP required  1 G3P can be taken out of the cycle every 3 turns, to go toward making glucose

 1 carbon dioxide is fixed per turn of the cycle  Each turn takes 3 ATP and 2 NADPH, made in the light reactions (lots of energy!)  To make one glucose, it takes six turns of the cycle

 In the light independent reactions of photosynthesis...