The Light Independent Reaction (and you thought we were done)

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I'm actually serious. We are done. After this post, you will know the process of photosynthesis in its basics. Although, I might still write another couple, to sum it up a little more cohesively. Also if you can't learn in paragraph form, I sincerely apologize... On with the show! I should probably mention that the goal of photosynthesis is to make glucose... Yeah sorry about that.

We now move from the grana to the stroma of the chloroplast. Fun stuff. There we meet the Calvin Cycle. Not the Krebs Cycle. Don't get the two mixed up. I know I do. CALVIN CYCLE. Wonderful. Now we can move on. As we established with cellular respiration a cycle means it is continuous. This time, however, it is not oxaloacetate that we start off with, but a molecule called Ribulose Bisphosphate (RuBP). Unless unlike oxaloacetate it is a 5 carbon compound. Then in a process called carbon fixation, a CO2 molecule binds with RuBP. This reaction is catalyzed by enzyme RuBP carboxylase (Rubisco for short).

This creates a highly unstable 6 carbon molecule, which immediately splits into two 3 carbon molecules called glycerate-3 phosphate, GP (not G3P, which is glyceraldehyde 3 phosphate and what we made during glycolysis). GP is then reduced by NADPH and ATP (old friends from the light dependent reaction), which ultimately gives us a different 3 carbon molecule called TP (triose phosphate). TP now faces the most important decision of its life. To leave home (the cycle) and become a sugar phosphate (such as glucose), or follow in his father's footsteps and convert back to a RuBP molecule. Most TP molecules don't have the guts to leave the comfort of home and are thus converted back into TP with the help of ATP. And thus the cycle begins again.

Ta for now.