Question

Light independent reactions/ calvin cycle

1. Where does the Calvin cycle take place? 2. Before the Calvin cycle begins, where is the energy stored? 4. What are the inputs to the Calvin cycle? Where do they come from? 5. Circle the letter of each statement that is true about the Calvin cycle. Correct the false statements. a. The main products of the Calvin cycle are six carbon dioxide molecules. b. Carbon dioxide molecules enter the Calvin cycle from the atmosphere. C. Energy from ATP and high-energy electrons from NADPH are used to convert 3-carbon molecules into similar 3- carbon molecules. d. The Calvin cycle uses six molecules of carbon dioxide to produce a single 6-carbon sugar molecule. 6. What are the products of the Calvin cycle?

Answer 1

1. calvin cycle occurs in stroma of chloroplast.  ATP and NADPH produced during the light reaction are used in the Calvin cycle to make sugar.

2. the energy is stored in ATP and NADPH which is produced during the light reaction. the reduction and regeneration steps of calvin cycle needs energy where ATP and NADPH are used.

4. CO₂, ATP, and NADPH are the  inputs to the Calvin cycle. plant absorbe CO₂ from the atmosphere through stomata, and the ATP and NADPH come from the light-dependent reaction. The CO2 is utilised for the carboxylation of RuBP. This reaction is catalysed by the enzyme RuBP carboxylase which results in the formation of two molecules of 3-PGA.

5.a. False . The final product of the Calvin cycle is glucose which is produced by fixing CO2 using ATP and NADPH

b. true. CO₂ comes from the atmosphere through stomata of plant

c. True. CO2 is fixed to form 3-Phosphoglycerate, a 3 carbon molecule which is unstable. it is then converted into a stable compound called glyceraldehyde-3-phosphate (G3P) which is also a 3 carbon molecule

d. True.  six turns of the CO2 fixation happens, when two molecules of glyceraldehyde-3 phosphate can be combined to make a glucose molecule.

6.  The final product of the Calvin cycle is glucose. CO2​ combine with RuBP acceptors, making glyceraldehyde-3-phosphate (G3P) which is converted into glucose.