Summary of the calvin cycle

QUESTION 5 This question explores the Calvin cycle in plants. A summary of the three stages of CO, assimilation in photosynthetic organisms is shown below (Fig. 20-31 from the text book). All the reactions of the Calvin cycle in detail are shown on the last page. Only the first three reactions are directly involved in carbon-fxation, assimilation and reduction, to Stage 3: ATP3 Regeneration of (3) Stage 1a Ribulose 1.5 e (GAP). The rest of the pathway results in the regeneration of ribulose ,5-bisphosphate (RuBP), the molecule that CO, reacts with at the beginning of the cycle. Stage 21 NADP We should be able to make some reasonable predictions on certain reactions of the Calvin cycle based on what we know of the glycolysis and the T cycle. G) NADPH+* ADP 6) 6 a) Reaction : This first reaction involving CO, is a complicated reaction and is not similar to any reaction we have seen in glycolysis, TCA or the pentose phosphate pathway. Do not wory about the details. b) Reaction 2: Here, ATP is used to phosphorylate a carboxlate group. i. Why is ATP used to donate a phosphoryl group, and not PI? ii. Why is this step of phosphorylating a carboxylate group necessary? BIOL201 2018W2-all rights reserved Problem Set g Page 3 ofs c) Reaction 3: In this reaction, a carbon atom is reduced. i. Which carbon atom is reduced? ii. How can you discern the oxidation/reduction state of a carbon atom in this reaction? ii. Which groups serve as the nucleophile and electrophile in this reaction? d) Reaction 4A and 4B:the to reactions are identical, and they use two of the six GAP molecules generated in Reaction 3. Which Glyco reaction is this reaction similar to? e) Reaction 5,7, 8, 10: All four of these reactions involve the making andor breaking of carbon-carbon bonds. i. Reaction 5 is the reverse of which Glyco reaction? i. Which of these reactions require thiamine pyroposphate (TPP) as a cofactor and which do not? Explain f) Reaction , 12, 13: What types of reactions are these? g) Reaction 14: ATP is used to phosphorylate an alcoholic hydroxyl (OH) group, why is ATP used as the source of h) Several of the reactions in the Calvin cycle are identical to those in glycolysis, yet they proceed in the opposite ) Name the classes of enzymestttalyze reactions 2 through 14 the phosphoryl group here, and not a Pi? direction. How is this possible in the same cell?