Calvin Cycle

1. Calvin Cycle • The Calvin Cycle makes sugar from the atoms in CO2 plus the H+ ions and electrons carried by NADPH. • The Calvin Cycle takes place in the stroma • The Calvin Cycle uses the ATP that was created in the Light Reactions to make sugar.

2. Calvin Cycle • Carbon fixation: carbon dioxide is added to (fixed) into an existing 5 carbon sugar. It splits into 3 carbon sugars. • The electrons and H+ ions from NADPH are added to the 3 carbon sugars forming G3P. ATP is needed. • One G3P molecule leaves the cycle, it is the building block of glucose and other organic molecules. • The G3P is turned back into RuBP (the 5 carbon sugar we started with). ATP is required.

3. Calvin Cycle • Inputs: CO2, NADPH, ATP • Outputs: C6H12O6 (sugar) • The sugar can be converted to sucrose, starch or cellulose. • Leaf cells can export sucrose thru veins to supply the rest of the plant with energy • The sugar can be converted to starch, which the plant can use during the night for energy. • The carbon skeletons can be used to form lipids, proteins, and other molecules the plant needs for growth or maintenance.

4. Photosynthesis 6CO2 +12 H2O  C6H12O6 + 6O2 + 6H2O

5. Converting sunlight to sugar • Complete Reflect & Connect #1-5 on page 334 • Read “Photosynthesis Isn’t Just For Plants” p. 335. • Why? Because it’s interesting and you’ll be able to impress your friends at parties  • Plus, I’ll put a bonus question on the next quiz from this reading.