Question

Calvin Cycle – What is it for? What feeds into it? What is produced? How is CO2 fixed?

Photorespiration – How does the [CO2]/[O2] ratio determine what is produced?

Answer 1

1 - The calvin cycle is a set of chemical reaction that take place in chloroplast during photosynthesis. The calvin cycle uses the energy from short lived electronically excited carriers to convert carbon dioxide and water in to organic compound that can be used by the organism. ATP AND NADPH produced by the light reaction are use by the calvin cycle to reduce carbon dioxide to sugar. In fixation the firdt stage of the calvin cycle, light independent reactions are initiated CO2 is fixed from an inorganic to an organic molecule.In second stage, ATP and NADPH are use to reduce 3-PGA into G3P ; then ATP and NADPH are converted to ADP and NADPH are converted to ADP and NADP+.

2 - The relative low ratio of CO2 to O2 of mesophyll fluids in contact with 0.04 means that in atypical plant the calvin cycle only occur three times then faster then photorespiration it does use oxygen and it does produce carbon dioxide and it uses a sugar phosphate as it primary fuel.