1. Review Questions for Photosynthesis

2. Match the processes/sets of reactions with the descriptions. Each question can have more than one answer. 1.Requires CO2 2.Requires water 3.Glucose is a product 4.Oxygen is a product 5.Occurs in the stroma 6.Occurs in the thylakoid membrane 7.NADP+ is required to go in 8.NADPH is required to go in 9.Carbon dioxide is reduced 10.NADPH is oxidized to form NADP+ 11.Makes ATP 12.NADP+ is the final electron acceptor A.Light reactions B.Dark reactions C.Calvin cycle D.Electron Transport Chain E.Chemiosmosis B, C A, D B, C A A, D, E A, D B, C A, E A, D

3. Match the processes/sets of reactions with the descriptions. Each question can have more than one answer. 1.Requires enzymes located in the stroma. 2.Makes use of ATP synthase. 3.Uses cytochromes 4.NADP+ is reduced 5.Creates a hydrogen ion gradient 6.Includes cyclic & noncyclic photophosphorylation 7.Driven by the energy of a proton gradient 8.Is part of cellular respiration 9.Provides energy for the dark reactions B, C A, E A, D D A D, E E A.Light reactions B.Dark reactions C.Calvin cycle D.Electron Transport Chain E.Chemiosmosis A, D, E

4. What happens in A? A B C D (the line) E Glycolysis and fermentation Anaerobic processes Formation of 2 ATP by substrate-level phosphorylation

5. What happens in B? A B C D (the line) E Dark/Calvin cycle reactions occur here so all the enzymes for these reactions are located here CO 2 is fixed into an organic molecule CO 2 is reduced by NADPH to produce PGAL/G3P NADPH is oxidized to form NADP+ ATP is used up & ADP is produced RuBP is regenerated STROMA

6. What happens in C? A B C D (the line) E Hydrogen ions (protons) are pumped (actively transported) here by the electron transport chain pH is lowered because of added H+ (pH=5 when light is shining on chloroplast) Thylakoid space

7. What happens in D? A B C D (the line) E Light reactions – cyclic & noncyclic photophosphorylation Water is split using light energy the electron transport chain located here actively transports hydrogen ions (protons) into the thylakoid space Oxidation-reduction reactions ATP & NADPH synthesis on the outside (stroma side) surface Chemiosmosis of ATP Thylakoid membrane

8. What does this represent? Identify A through F. A B C D E F Chloroplast A – water (H 2 O) B – Oxygen gas (O 2 ) C – Carbon dioxide (CO 2 ) D – Glucose (C 6 H 12 O 6 ) E – ATP and NADPH F – ADP and NADP +

9. Put the descriptions where they belong Non-cyclic photophosphorylation Cyclic photophosphorylation Occurs in the thylakoid membrane Produces ATP Produces NADPH More primitive/less evolved Uses photosystem I (P700) Uses photosystem II (P680) Splits water Releases oxygen gas (O 2 ) Uses the electron transport chain Electrons return to P700 (PS I) Electrons are excited by light Photolysis

10. Put the following in order of the passage of energy during photosynthesis. ATP Light Electron Transport Chain Glucose Chlorophyll Hydrogen ion (H+)/ proton gradient 1.Light 2.Chlorophyll 3.Electron Transport Chain 4.Hydrogen ion (H+)/ proton gradient 5.ATP 6.Glucose

11. True or False: If the statement is false, replace the underlined word/phrase to make the statement read true. 1.Water is a reactant for the light reactions. 2.G3P is a product of the Calvin cycle. 3.Carbon dioxide is oxidized during the process of photosynthesis. 4.Water is oxidized during the process of photosynthesis. 5.The enzymes that carry out the Calvin cycle are only active in the dark. 6.The reactant for the reduction phase of the Calvin cycle is CO 2. TRUE FALSE – reduced (since it picks up H atoms from NADPH) TRUE – it loses electrons/hydrogen FALSE -- active in light or dark – as long as there is ATP and NADPH around. FALSE – carbon fixation.

12. True or False: If the statement is false, replace the underlined word/phrase to make the statement read true. 1.The carbon fixation stage of the Calvin cycle begins when CO 2 joins with oxaloacetate, a 4-carbon compound. 2.Oxygen is a product of the Calvin cycle. 3.The final electron acceptor in the electron transport chain within a chloroplast is NAD +. 4.The final electron acceptor in the electron transport chain within a mitochondrion is oxygen. 5.The high energy molecules that provide the energy to reduce CO 2 are ADP and NADP + 6.The product for the regeneration phase of the Calvin cycle is CO 2. FALSE – RuBP, a 5-carbon. FALSE – noncyclic photophosphorylation/light reactions. FALSE – NADP+. TRUE FALSE – ATP & NADPH FALSE – RUBP

13. Which of the following does not belong? Write one or two sentences using the other words that explain how all the other words are related. 1.Photolysis, Calvin cycle, photophosphorylation, thylakoid membrane, chemiosmosis 2.Carbon fixation, reduction, regeneration, RuBP, oxaloacetate, PGAL, rubisco 3.G3P, NADPH, ATP, 3PGA, RuBP Within the thylakoid membrane in a chloroplast, noncyclic photophosphorylation occurs where water is split using light energy in a process called photolysis. The electrons from water are energized and passed down an electron transport chain which sets up a H + ion (proton) gradient whose energy is used to make ATP through chemiosmosis. During the Calvin cycle, carbon fixation (catalyzed by the enzyme rubisco) is followed by reduction and regeneration to re-form RUBP which was a reactant in carbon fixation in the first place. PGAL or G3P is the 3-carbon product of the Calvin cycle/dark reactions. During the reduction phase of the Calvin cycle, 3PGA are reduced and phosphorylated by NADPH and ATP and G3P is produced.