Photosynthesis Past Paper PDF

Name_________________________________ Date ___________ Period________ PHOTOSYNTHESIS STARTS WITH 1. Molecules that collect light energy are called _P_ __ __ __ __ __ __ __. igment 2. Chlorophyll a and b absorb _B_...

Name_________________________________ Date ___________ Period________ PHOTOSYNTHESIS STARTS WITH 1. Molecules that collect light energy are called _P_ __ __ __ __ __ __ __. igment 2. Chlorophyll a and b absorb _B_ __ lue__ __-_V_ __ __ __ __ __ and _R_ ed iolet __ __ wavelengths of light best. hlorophyll 5. _C_ __ __ __ __ __ __ __ __ __ __ is the main light absorbing pigment found in green plants. 3. Plants “look” green because chlorophyll _R_ __ __ __ __ __ __ __ green light. eflects 4. Organisms, like green plants, that can make their own food using energy from the sun are called _A_ __ __ __ __ __ __ __ __ __. utotrophs 5. The gel-filled space inside the chloroplast surrounding the thylakoid stacks is called the _S_ __ __ __ __ __. troma 6. _P_ __hotosystem __ __ __ __ __ __ __ __ __ __ I and II contain chlorophyll and absorb light energy during the _L_ __ight__ __ __ _D_ __ __ __ __ __ __ __ __ reactions. ependent hylakoid 7. During the light dependent reactions, H+ ions build up in the _T_ __ __ __ __ __ __ __ __ space when _W_ ater __ __ __ __ molecules are split. 8. The enzymes for the light dependent reactions are found in the _T_ __ __ __ __ __ __ __ __ hylakoid embrane _M_ __ __ __ __ __ __ __ , while the Calvin cycle happens in the _S_ __ __ __ __ __. troma 9. The stacks of thylakoids found inside chloroplasts are called _G_ __ __ __ __. rana 10. The light independent reactions are also called the _C_ __ ycle__ __ __. __ __ __ __ _C_ __ alvin 11. Carbon and oxygen from _C_ arbon __ __ __ __ __ _D_ __ __ __ __ __ __ end up as part of a dioxide _G_ __ __ __ __ __ __ molecule following the Calvin cycle. lucose 12. _A_ __ ADPH TP __ and _N_ __ __ __ __ are made during the _L_ __ ight __ __ __ dependent reactions and carry energy and high energy electrons that are used during the Calvin cycle to produce _S_ __ __ __ __ __, like glucose. ugar 13. The O in H2O is given off as_O_ __ __ __ __ __ gas to the atmosphere when water is split during xygen the light dependent reactions. 14. Proteins in living things that help chemical reactions happen are called _E_ __ __ __ __ __ __. nyzmes 15. Electrons are transferred along the membrane from Photosystem II to Photosystem I using the _E_ __lectron __ __ __ __ __ __ _T_ __ ransport __ __ __ __ __ __ __ _S_ __ystem __ __ __ __. 1 16. Orange and yellow colored pigments called _C_ __ __ __ __ __ __ __ __ __ __ absorb different arotenoids wavelengths of light and help chlorophyll use more of the sun’s energy. 17. _T_ __ __ __ __ __ __ __ __ __ __ , amount of _W_ __ emperature ater__ __ __ , and _L_ __ ight__ __ __ intensity are all factors that affect the rate of photosynthesis. * * * * * * * * * * * * * * * ENERGY AND LIFE MULTIPLE CHOICE: CIRCLE ALL THE STATEMENTS THAT ARE TRUE OR COMPLETE THE STATEMENT. THERE MAY BE MORE THAN ONE CORRECT ANSWER. Which molecule stores more than 90 times the energy in an ATP molecule? C A. ADP B. water C. glucose D. adenine All organisms get the ENERGY they need to regenerate ATP from __________________________ foods like glucose A. phosphates B. foods like glucose C. organelles D. ADP Which of the following are TRUE about ATP? A. ATP consists of ribose sugar, adenine, and 3 phosphate groups B. ADP forms when ATP loses a phosphate and releases energy. C. Used ATP is discarded by the cell as waste. D. ATP provides energy for active transport in cells. What is it called? DESCRIPTION GIVE 2 EXAMPLES Autotrophs Organisms that can make their Algae and grass own food Heterotrophs Organisms that obtain energy Humans, from the food they eat tigers What is the ultimate source of energy autotrophs use produce their own food? _____________________ sunlight 2 On the line below each picture, classify the organism as either an AUTOTROPH or a HETEROTROPH. _______________________ Heterotroph _______________________ Autotroph _______________________ Heterotroph Hint: What color are mushrooms? NAME THE CHEMICAL COMPOUND SHOWN BELOW THAT CELLS USE TO STORE ENERGY. _________ ATP LABEL THE PARTS THAT MAKE UP THIS MOLECULE: A= _________________________________ Adenine ribose B= __________________________________ 3 phosphate groups C=___________________________________ WHAT DOES ATP STAND FOR? Adenine A_______________________ T________________________________________ Triphosphate 2 HOW MANY PHOSPHATES ARE IN ONE MOLECULE OF ADP? ____________ HOW IS ATP MADE FROM ADP? ADP combined with an extra phosphate group create ATP. __________________________________________________________________________________ USE the words: ENERGY STORING and ENERGY RELEASING to label what is happening in the reactions shown below: Energy Released _____________________________________ Energy Stored ____________________________________ 3 Name 3 cellular activities that use the energy stored in ATP: Active Transport _______________________________________ Photosynthesis(Calvin Cycle) _______________________________________ Muscular Contraction _______________________________________ * * * * * * * * * * * * * * * PHOTOSYNTHESIS: An Overview CIRCLE ALL THAT ARE TRUE. Plants gather the sun’s energy with light-absorbing MOLECULES called __________________. pigments A. thylakoids B. pigments C. chloroplasts D. glucose Chlorophyll absorbs light very well in the _______________ regions of the visible spectrum. (Circle all that are true) A. blue-violet B. green C. red D. yellow reflects green light Most plants appear green because chlorophyll _________________________________________. A. reflects green light B. absorbs green light A student conducts an experiment by collecting the gas given off by a green plant in bright sunlight at room temperature. The gas being collected is probably ___________________. Oxygen A. ATP B. water vapor C. carbon dioxide D. oxygen Write the complete overall chemical equation for photosynthesis using chemical symbols instead of words: ___________ 6H20 __________________ + ___________________ 6CO2 → __________________ C6H12O6 + ___________________ 6O2 4 How many molecules of carbon dioxide (CO2) are used to make 1 molecule of glucose (C6H12O6) ? 1 2 3 6 12 In addition to water and carbon dioxide, what two things are required for photosynthesis to happen? Light _______________________ and _______________________ Chlorophyll * * * * * * * * * * * * * * * REACTIONS OF PHOTOSYNTHESIS MULTIPLE CHOICE: Circle the letter of the answer that best completes the statement or answers the question. Where are Photosystems I and II found? A. in the stroma B. in the thylakoid space C. in the thylakoid membrane D. in the Calvin cycle The Calvin cycle is another name for __________________________ A. photosynthesis B. the electron transport chain C. light-dependent reactions D. light-independent reactions Why does the space inside the thylakoid become positively charged during the light-dependent reactions? A. ATP synthase pushes H+ ions from the stroma across the membrane into the space B. H+ ions build up in the space as water is split C. Electrons have a + charge and are released here by Photosystem II D. Carbon dioxide builds up in the stroma CIRCLE ALL THAT ARE TRUE about the LIGHT DEPENDENT REACTION. A. High-energy electrons move through the electron transport chain. B. Pigments in photosystems II and I absorb light. C. ATP synthase helps H+ ions in the thylakoid space to pass through the membrane to the stroma. D. ATP and NADPH are used to produce high-energy sugars. CIRCLE ALL THAT ARE TRUE about the CALVIN CYCLE A. ATP is produced by ATP synthase and oxygen is released B. It is also called the light-independent reaction. C. ATP and NADPH from the light-dependent reactions are used here D. High energy sugar compounds are made from CO2 5 Which step is the beginning of photosynthesis? A. Pigments in photosystem I absorb light. B. Pigments in photosystem II absorb light. C. High energy electrons move through the electron transport chain. D. ATP and NADPH produce high energy sugars. CIRCLE ALL OF THE FOLLOWING THAT ARE FOUND INSIDE THE THYLAKOID MEMBRANE. A. electron transport chain B. photosystem I C. photosystem II D. ATP synthase Which molecule acts as a carrier for high energy electrons during photosynthesis? A. ATP B. H2O C. NADP+ D. CO2 How is the Calvin cycle different from the light-dependent reactions? A. It takes place in chloroplasts. B. It takes place in the stroma. C. It requires light. D. It takes place in the thylakoid membrane Oxygen produced during the light-dependent reaction is __________________________. A. used in the Calvin cycle to make sugar B. joined with the NADPH to make water C. is released into the atmosphere D. None of these, oxygen is NOT produced by the light-dependent reaction * * * * * * * * * * * * * * How does NADP+ become NADPH? 2 Electrons and one hydrogen ion(positive) are added. ___________________________________________________________________________________ Name 3 factors that affect the rate at which photosynthesis occurs. 1. ___________________________ Carbon dioxide concentration 2. ___________________________ Light intensity 3. ___________________________ Temperature 6 MODIFIED TRUE or FALSE Circle T if the statement is TRUE. Circle F if the statement is FALSE and use the blank provided to correct the underlined word/phrase. T F Increases Increasing light intensity decreases the rate of photosynthesis. _____________________ T F Carbon dioxide molecules enter the light-dependent reactions from the atmosphere. light-independent reactions ______________________ T F Photosynthesis uses energy from ATP and high energy electrons from NADPH produced in the light-dependent reactions to make glucose in the Calvin cycle. ___________________ T F Oxygen(O2) The light-dependent reaction produces ATP, NADPH, and carbon dioxide. _____________ T F ATP synthase spins like a turbine as H+ ions pass through it to generate ATP. __________ T F Electrons are energized twice during photosynthesis. __________ USE THE LETTERS IN THE DIAGRAM AT THE LEFT TO IDENTIFY: B ______ stroma ______ A thylakoid ______ C granum * * * * * * * * * * * * * * * COLOR THE DIAGRAM AS DESCRIBED: Color the energy from sunlight YELLOW Color the two places where light energy enters the reactions ORANGE Color the hydrogen ions RED Color the electrons GREEN Color the thylakoid membrane BLUE On which side of the membrane would you find the STROMA? A or B (Hint: look to see where NADPH is being made) 7 On which side of the membrane is the INNER THYLAKOID SPACE? A or B (Hint: look to see where water molecules are being split) * * * * * * * * * * * * * * * Where does ATP formation happen? Stroma inner thylakoid space Add an equation to the diagram in the correct location that shows the formation of ATP from ADP. ATP ADP + P * * * * * * * * * * * * * * * USE WORDS FROM THE WORD BANK TO FILL IN THE CHART COMPARING AND CONTRASTING THE LIGHT-DEPENDENT REACTIONS AND THE CALVIN CYCLE: (You can use them more than once!) in stroma in thylakoid membrane O2 ATP CO2 H2 O NADPH Requires light Doesn’t require light SUGARS (glucose) LIGHT-DEPENDENT REACTIONS CALVIN CYCLE LOCATION Thylakoid Membrane Stroma REACTANTS Requires light, H2O ATP, NADPH, CO2 ATP, NADPH PRODUCTS Glucose, PGAL, NADP+, ADP, Pi LIGHT? Requires Light Doesn't require light 8 THINK ABOUT IT C Which of these graphs represents the effect of temperature on the rate of photosynthesis? ______ (Hint: Many molecules that help with photosynthesis are enzymes) Enzymes only work best at a certain level if it is higher than that temperature EXPLAIN YOUR ANSWER. ___________________________________________________________ then it will denature and stop working _________________________________________________________________________________ D Which of these graphs represents the effect of light intensity on the rate of photosynthesis? ______ When light intensity works the plant will recieve more light which will EXPLAIN YOUR ANSWER. ______________________________________________________________ exponentially increase the process of photosynthesis. ___________________________________________________________________________________ 9  Chemiosmosis - The Mechanism of ATP Synthesis in Chloroplasts The thylakoid membrane is composed of a phospholipid bilayer (color phospholipids "B" light blue) and photosystem I and photosystem II. Although they both work simultaneously, it is best to look at them one at a time, starting with photosystem II. The first and most important event in either system is the capturing of light energy (color "E" orange) by the pigments associated with each photosystem. Color the pigments of Photosystem II (P2) dark green and the pigments of Photosystem I (P1) light green. Pigment 680 (color dark green) is associated with Photosystem II, and Pigment 700 (color light green) is associated with Photosystem I. When a photon of light strikes the reaction center of Photosystem II, it excites an electron. Two water molecules bind to an enzyme that splits water into hydrogen ions (protons) and releases an oxygen atom. Color the protons (H+) yellow and the oxygen atoms (O2) red. This process is called PHOTOLYSIS and is illustrated by the arrows labeled "L", which you should color pink. Two electrons are released in this process, and these electrons can be traced through photosystem II and photosystem I. Color the electrons (e) grey. Two oxygen atoms will join together to create an oxygen molecule which is released from the plant as a byproduct of the entire reaction. The primary electron acceptor for the light-energized electrons leaving photosystem II is plastoquinone (color PQ purple). The reduced plastoquinone passes the excited electrons to a proton pump embedded in the membrane called the b6-f complex (color dark blue). This proton pump moves protons (H+) atoms across the membrane against their concentration gradients, which eventually causes a build- up of protons in the thylakoid space. This will be important later. The thylakoid membrane is NOT permeable to protons, so they may only cross the membrane via transport proteins. The protons will exit the thylakoid space via a special channel provided by ATP Synthetase 1 (color "S" pink). The protons move through the ATP synthase with the concentration gradient, which allows them to do work-namely drive ATP synthesis. As protons pass through the ATP synthetase, ADP is phosphorylated (-P added) to ATP and released into the stroma. The process of making ATP is called PHOTOPHOSPHORYLATION. The arrow labeled "Z" represents photophosphorylation - color orange. This ATP (color orange) is now on its way to the Calvin Cycle where it will be used to generate glucose. The electron that was used in Photosystem II is just sitting around, all de-energized but its story is not finished. A small protein called plastocyanin (color brown) carries the electron to Photosystem I. Light absorbed by photosystem I energizes this electron and passes it to another primary electron acceptor called ferredoxin (color "Fd" turquoise). The enzyme NADP Reductase (color "R" dark purple) transfers these electrons to NADP to form NADPH. The electron is now on its way to the Calvin Cycle as part of an NADPH molecule (color light purple). Electrons lost from photosystem I are replaced by electrons generated from photosystem II. Remember you colored the electrons grey, now color the path they take through both systems grey also (represented by the arrow labeled "X"). Remember you colored the protons yellow, now color the path they take through the systems in yellow also (represented by arrows labeled "Y"). 2  Colors Phospholipids - light blue Electron path (X) - grey Light energy - orange Plastoquinone - purple Photosystem II - dark green b6-f complex - dark blue P680 - dark green ATP Synthetase - pink Photosystem I - light green Photophosphorylation (Z) - orange P700 - light green ATP - orange Protons - yellow Plastocyanin - brown Proton path (Y)- yellow Ferredoxin - turquoise Oxygen - red NADP Reductase - dark purple Photolysis - pink NADPH - light purple Electrons - grey Questions: 1. Trace the flow of protons through the thylakoid. 2. Trace the flow of electrons through the thylakoid 3. Explain the role of each of the following: ---- P680 The pigment used for photosystem II ---- P700 The pigment used for photosystem I ---- ATP Synthetase Moves hydrogen ions out of the thylakoid producing a phosphate ---- Plastocyanin A protein that carries electrons to photosystem I ---- Plastoquinone A primary electron acceptor ---- Ferredoxin A primary electron acceptor ---- NADP Reductase Transfers electrons to NADP to make NADPH 4. Explain how the concentration gradient affects the process of ATP synthesis. The concentration gradient forces the proton through the membrane provinding free energy to be used to make ATP 3 4  Chloroplasts Worksheet Plant cells​ and ​some Algae​ contain an organelle called the chloroplast​. The chloroplast allows plants to harvest ​energy​ from ​sunlight to carry on a process known as​ Photosynthesis​. Specialized pigments in the chloroplast (including the common green pigment ​chlorophyll​) absorb sunlight and use this energy to combine ​carbon dioxide​ and ​water​ and make GLUCOSE​ and ​OXYGEN​. The complete the chemical reaction for Photosynthesis is: 6 CO​2​ + 6 H​2​O + energy (from sunlight) C​6​H​12​O​6​ + 6 O​2 RAW MATERIALS ENERGY PRODUCTS In this way, plant cells manufacture ​glucose​ and other ​carbohydrates ​ that they can store for later use. Photosynthetic cells found mainly in the leaves​ may have ​thousands ​of chloroplasts. QUESTIONS: 1. What type of cells contain chloroplasts? Mesophyll cells 2. What is the energy autotrophs use to make their own food? Energy from the sun 3. The food making process is called ___________________. photosynthesis 4. What are the raw materials for photosynthesis? Carbon dioxide, water, and sunlight. 5. What simple sugar is produced? Glucose 6. What gas is USED? ________________ Carbon dioxide RELEASED? ________ oxygen 7. Where are most photosynthetic cells in plants found? Leaves 8. About how many chloroplasts can be found in photosynthetic cells? Thousands 1  Chloroplasts are double membrane organelles with a smooth outer membrane and an inner membrane folded into disc-shaped sacs called thylakoids​. ​Color and label​ the outer membrane light green. Thylakoids, containing chlorophyll and other ​accessory pigments (red, orange, yellow, brown)​, are in stacks called ​granum ​(​grana​, plural). ​Color and label​ the grana (STACK) dark green in Figure 1. Grana are connected to each other by structures called ​lamellae​, and they are surrounded by a gel-like material called ​stroma.​ C​ olor and label​ the ​lamellae brown​ in figure 1. Color and label​ the stroma light blue in Figure 1. FIGURE 1-CHLOROPLAST 9. How many membranes surround a chloroplast? two membranes 10. The outer membrane is S____________. mooth 11. The INDIVIDUAL SACS formed by the inner membrane are called _________________ thylakoids and are arranged in ___________ stacks like pancakes. 12. What pigment is found inside a thylakoid? What color will it be? Chlorophyll and other accessory pigments. It will be green, orange, red, brown, and yellow 13. Other pigments that trap sunlight are called A_____________ ccessory pigments. What colors are these pigments? Red, brown, orange, and yellow 2  14. STACKS of thylakoids are called G___________ rana (plural) or GRANUM (singular). 15. Stacks or grana are connected to each other by _____________. lamellae Light-capturing pigments in the grana are organized into ​photosystems​. On Figure 2, ​color and label​ a single thylakoid (SINGLE DISK) dark green. In figure 2, c ​ olor and label​ a granum (STACK) red. FIGURE 2-THYLAKOID 3  Photosynthesis PowerPoint Question Guide Overview 1. Photosynthesis is a(n) ___________ anabolic reaction because it combines simple molecules into more complex molecules. 2. a. Is photosynthesis an endergonic or exergonic reaction? Endergonic b. Explain why. It is endergonic because it stores energy c. Energy from the __________ the sun is stored in the bonds of the sugar ___________. molecules 3. What serves as the carbon source for photosynthesis? carbon dioxide 4. Sunlight is absorbed as packets of energy called ____________. photons 5. Besides CO2, ___________ water is also used in photosynthesis to produce _____________ organic macro molecules such as the sugar _____________. glucose Where Does Photosynthesis Occur? 6. Plants can make their own food so they are called ______________. Autotrophs 7. Photosynthesis occurs mainly in the _____________ leaves of plants. 8. Pores on the underside of leaves are called ____________, stoma while the cells in leaves that contain chlorophyll are called ______________ mesophyll cells. 9. The organelle in mesophyll cells that contains chlorophyll is called the _______________. chloroplasts 10. Name two gases exchanged through the stomata of a leaf? Carbon dioxide and oxygen 11. Besides gases, ___________ water vapor can be lost from a leaf. 12. Sketch a stoma and label the cells that open and close the pore. Include arrows to show the direction of gas movement. oxygen Guard cell Guard cell Carbon dioxide  13. In what cell in a leaf does photosynthesis occur? Sketch and label one of these cells. Mesophyll cells Nucleus Chloroplasts Central Vacuole Cell Wall 14. Sketch and label a chloroplast. Thylakoid Outer membrane Stuff inside is Inner membrane stroma Granum 15. How many membranes does a chloroplast have? Two 16. Describe the outer membrane of a chloroplast. A semi permeable membrane that encloses the inner membrane and the contents inside the inside of the chloroplast 17. What is the thick fluid in the inside of a chloroplast called? Stroma 18. ______________ Chloroplasts are organelles containing chlorophyll. 19. Stacks of thylakoids are called _____________ Granums and are ____________ stacked on to each other. 20. Grana make up the __________ inner membrane of a chloroplast. Why Plants Are Green? cal 21. Why are plants green? Chlorophyll pigments harvest energy by absorbing certain wavelengths, but plants are green because the green wavelength is reflected not absorbed. 22. a. Chlorophyll molecules are located in the ___________ thylakoid membranes and harvest light _____________ energy. b. Chlorophyll has a _____________ magnesium ion in their center. 23. Chlorophyll and other pigments absorb ______________ wavelengths of light from 400nm to 700nm. 24. Chlorophyll absorbs __________ blue and ________ red colors of light the best. Fall Colors 25. During the fall, what happens to the amount of chlorophyll being produced by plants? Green chlorophyll pigments are greatly reduced revealing the other pigments 26. ____________ Carotenoids are plant pigments that include __________, red orange, and __________ colors. yellow 27. Why do leaves turn colors in the fall? Green chlorophyll pigments are greatly reduced revealing carotenoids that turn other colors. 28. What is a redox reaction? The transfer of one or more electrons from one reactant to another 29. __________ Oxidation is the loss of electrons, while _________ Reduction is the addition or gaining of electrons. 30. Write the summary equation for photosynthesis and label each compound. 6CO2 + 6H2O = C6H12O6 + 6O2 Carbon dioxide water oxygen glucose 31. _______ water is oxidized and ________ oxygen is reduced in photosynthesis. Cellular Energy 32. What is the ultimate energy for life on Earth? Sunlight sugars 33. Plants store ___________ energy in the chemical bonds of ____________. 34. Chemical ___________ energy is released from sugars during _____________________. cellular respiration 35. ATP stands for __________________________. Adenosine triphosphate 36. Name the parts of ATP? Nitrogen base - Adenine 3 phosphate gropus Ribose(pentose(5c) sugar) 37. Describe the bond attaching the last phosphate group to ATP. The last phosphate group is bonded with a high energy chemical bond 38. What happens if the last phosphate bond on ATP is broken? Energy is released for cells 39. Name 3 things released when the last phosphate bond on ATP is broken. Releases energy for cells to use, forms ADP, and produces a free phosphate group  40. The process of making ATP from ADP and a free phosphate is called ______________. phosphorylation 41. Energy released from is available for cellular _______________. work Parts of Photosynthesis Light Dependent Reaction (Produces energy from solar power (photons) in 42. Name the first part of photosynthesis. the form of ATP and NADPH.) 43. Light reactions use energy from the _________ sun to produce _______ ATP and the energy carrier _______. NADPH 44. The second part of photosynthesis is called the __________ Calvin or Light Independent cycle. 45. Does the Calvin cycle require light energy? It doesn't directly require light energy 46. The Calvin cycle is also called the __________ carbon fixation or the ______ C3 pathway. 47. Where do the light reactions of photosynthesis take place in a chloroplast? Thylakoid membranes 48. Name the two possible routes energized electrons can take during the light reactions of photosynthesis. Cyclic electron flow and noncyclic electron flow 49. The cyclic electron flow only uses ______________ Photosystem I in the thylakoid membranes and has chlorophyll a molecules at the photosystem's reaction center that absorbs ________ 700m wavelength of light. 50. The only energy generated in the cyclic electron flow is _________. ATP 51. Diagram the cyclic flow of electrons. Primary electorn acception e- Sun Creates ATP by electron transport chain ATP e- Chlorophyll P700 e- 52. The noncyclic electron flow uses both photosystem I_____ and _____. II  53. The chlorophyll molecules at the reaction center of photosystem II absorb wavelengths of ________nm. 680 54. The noncyclic electron flow generates the gas ________ oxygen , as well as _______ ATP and the energy carrier _________. NADPH 55. Both photosystem I and II use the ________ Electron transport ______ chain (ETC) to produce ATP. 56. Label the diagram for the noncyclic flow of electrons. Electron acception Enzyme reaction Electron acception ETC Sun NADPH P68 P70 H20 gets split Photosystem 1 Photosystem 2 Photosystem? Photosystem? 57. Water is split in ___________ Photosystem 2 , while NADPH is made in ____________. photosystem 1 58. Oxygen made by plants comes from the splitting of ___________. water 59. _______________ Chemiosmosis powers ATP synthesis in plants. 60. Where does chemiosmosis occur in plants? Occurs in the thylakoid membrane 61. ATP is made using the _________________ electron transport chain and the enzyme ___________. ATP synthase 62. ___________ hydrogen ions move through down their concentration gradient through the ______________ channels of the enzyme ATP _______________ synthase to form ATP from _________. ADP 63. ________ ATP is the energy molecule used by cells and must be remade by ATP ___________ synthase or chemiosmosis. 64. ATP _____________ synthase is the enzyme used to make ATP from ADP. 65. Most plants on Earth (80%) are known as ______ C3 plants and use the _________cycle calvin cycle to make sugars. 66. The Calvin cycle does ______ not require light energy and occurs in the _______ stroma of the chloroplast. 67. The energy for the Calvin cycle is ATP ________ and NADPH ________ made during the light reactions. 68. The gas _______ CO2 is used in the Calvin cycle to make the sugar __________. glucose 69. When conditions are hot and dry, __________ Stomates are closed to prevent water loss. 70. Name 2 plants that use different pathways to make food. C4 plant and CAM plants 71. Give several examples of C4 plants. Grasses, corn, sugarcanes 72. Photosynthesis occurs in what two places in C4 plants? Light reactions in mesophyll cells and calvin cycle in bundle sheath cells 73. C4 plants make a _______ 4C carbon sugar called malate in the mesophyll cells that enters bundle sheath cells. 74. The Calvin cycle takes place in __________ Bundle sheath cells in C4 plants. 75. Name two CAM plants. Cactus and Ice plants 76. CAM plants _________ close their stomata during the hot day and _______ open them at night. 77. In CAM plants, the _________ light reactions occur during the day, while the __________ calvin cycle occurs at night when the stomata open and let ________ carbon dioxide enter. 78. By closing their stomata during the day, CAM plants conserve __________. water