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AP Biology: Photosynthesis Flashcards

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6793007517Photosynthesis6CO₂ + 6H₂O + Light Energy -> C₆H₁₂O₆ + 6O₂0
6793024877PhotosynthesisCarbon Dioxide + Water + Light Energy -> Glucose + Oxygen1
6793030996LeavesMajor site of photosynthesis on a plant (part of plant).2
6793037719EpidermisOuter layer of cells on leaves that contain stromata.3
6793041075MesodermMiddle layer of cells in leaves that contain many chloroplasts.4
6793048253StromataOpenings in the epidermis of leaves that allow CO₂ to enter and O₂ and H₂O to exit as a vapor.5
6793058351RootPart of cell that absorbs water6
6793060995XylemPart of the cell that carries water up the plant from the roots.7
6793066446Autotrophic ProkaryotesThese types of cells lack chloroplasts and instead have chlorophyll built into their cytosol.8
6793078963Chloroplast9
6793082654ChloroplastThe organelle that is the major site for photosynthesis that contains chlorophyll.10
6793089643StromaThe portion of the choroplast that is contained within the inner membrane that has a low H+ concentration. Is the site of the calvin cycle. Also contains the thylakoids.11
6793098495ThylakoidA flattened membranous sac that contains chlorophyll located within the stroma of a chloroplast. Is the site of light reactions. An individual unit of a granum.12
6793106133Thylakoid SpaceThe space within the thylakoids that has a high H+ concentration.13
6793109602Thylakoid MembraneThe membrane that surrounds the thylakoids in the chloroplasts.14
6793118255Granum (Plural: Grana)A stack of thylakoids. One of these is joined to another by an elongated tube-like connection.15
6793129480Photosynthesis Light ReactionsIn this photosynthetic reaction, 2e- and 2H+ is taken from an H₂O molecule and light energy is used to boost them to higher energy levels. Some of this energy is used to make ATP and the rest of the high-energy molecules are attached to NADP+ molecules to make NADPH.16
6793157052Photosynthesis Calvin Cycle (Dark Reactions)In this photosynthetic reaction, ATP produced during light reactions is used. High energy e- and H+ molecules are taken from NADPH and are added to CO₂ molecules and glucose is produced "one carbon at a time" in the form CH₂O.17
6793195025Cyclic (Nonlinear) Electron Flow Light ReactionThe cyclic light reaction that uses only Photosystem I. This is a short circuit alternative path for photoexcited electrons typical in bacteria and some eukaryotes. 2e- molecules are excited by using light energy and are accepted by the 1° (primary) electron acceptor and then are passed down by other molecules to create an H+ gradient that allows for the production of ATP through chemiosmosis. Eventually the H+ molecules reach the bottom of the gradient to be excited and elevated once more. ETC is created over the thylakoid membrane.18
6793238004Photosystem IA photosystem that consists of a few 100 pigment molecules including chlorophyll a and b, and carotenoids. Uses the P700 reaction center to elevate electrons. Was discovered first, but functions second in linear electron flow.19
6793261898Chlorophyll AA specific form of chlorophyll used in photosynthesis. It is the principal photosynthetic pigment that absorbs violet-blue light and red-orange light.20
6793349857Chlorophyll BA specific form of chlorophyll used in photosynthesis. It is the accessory photosynthetic pigment that absorbs blue-green light and orange-yellow light.21
6793379080CarotenoidsA pigment used in photosynthesis. This substance both absorbs light (400-550nm, violet to green) and protects the chlorophyll from photodamage.22
6793320500P700 Reaction CenterThe reaction center that is present in photosystem I. The reaction center receives light energy that is absorbed by the chlorophyll and uses the energy to elevate the electrons. The number refers to the optimal wavelength of light that the reaction center absorbs.23
6793408425Noncyclic (Linear) Electron Flow Light ReactionThis noncyclic light reaction process utilizes both photosystem I and II. This is a linear light reaction common in plants. Photosystem II hydrolyzes water to produce .5O₂, 2H+, and 2e- molecules. The e- molecules are energized by the P680 reaction center and accepted by the 1° (primary) electron acceptor. The e- molecules move down and are accepted by other molecules. This creates an H+ gradient that is used to make ATP. When the e- molecules move down this first gradient and reach the bottom, they are accepted by the P700 reaction center and excited again. They are accepted by the 1° (primary) electron acceptor. The e- moves down again and creates another H+ gradient that's used to make more ATP. 2e- molecules along with H+ molecules are eventually accepted by NADP+ with the help of NADP+ reductase to form NADPH. ETCs are created over the thylakoid membranes.24
6793508367Photosystem IIA photosystem that utilizes chlorophyll a and b along with the P680 reaction center to excite electrons. Was discovered second, but functions first in linear electron flow.25
6793534054P680 Reaction CenterA reaction center present in photosystem II. The reaction center receives energy absorbed by chlorophyll and uses the energy to elevate electrons. The number refers to the optimal wavelength of light that it absorbs.26
6793559506Calvin Cycle (Dark Reactions)The portion of photosynthesis that occurs in the stroma in the absence of light. This process has 3 phases. Phase 1: Carbon Fixation, Phase 2: Reduction, Phase 3: CO₂ Acceptor Regeneration. This process creates glucose "1 carbon at a time" and "6 turns" of this cycle makes one glucose molecule.27
6793583547Phase 1 of the Calvin Cycle (Carbon Fixation, Per 1 Carbon)In this phase, an RuBP molecule accepts the CO₂ and RuBisCO fixes the carbon to the RuBP to form an unstable 6-carbon compound that breaks apart into two 3-PGA molecules. CO₂ becomes "fixed" from an inorganic form into organic molecules.28
6793722279Phase 1 of the Calvin Cycle (Carbon Fixation, Per 3 Carbon)In this phase, 3 RuBP molecules accept the 3 CO₂ molecules and RuBisCO fixes the carbon to the RuBP to form 3 unstable 6-carbon compounds that break apart into 6 3-PGA molecules. CO₂ becomes "fixed" from an inorganic form into organic molecules.29
6793640887Phase 2 of the Calvin Cycle (Reduction, Per 1 Carbon)The two 3-PGA molecules from the prior phase are converted into 2 DGPA molecules through the use of 2 ATP. The DGPA molecules are then converted into 2 3-PGAL molecules through the use of 2 NADPH molecules. The DGPA also lose a phosphorous molecule in the process of being converted into 3-PGAL. The ATP and NADPH molecules were produced in the light cycle.30
6793749621Phase 2 of the Calvin Cycle (Reduction, Per 3 Carbon)The six 3-PGA molecules from the prior phase are converted into 6 DGPA molecules through the use of 6 ATP. The DGPA molecules are then converted into 6 3-PGAL molecules through the use of 6 NADPH molecules. The DGPA also lose a phosphorous molecule in the process of becoming 3-PGAL. The ATP and the NADPH molecules were produced in the light cycle.31
6793701793Phase 3 of the Calvin Cycle (Regeneration, Per 1 Carbon)It takes 3 "turns" of the calvin cycle to fix enough net carbon to export 1 PGAL molecule, so therefore it takes 6 3-PGAL molecules to be present to export just one of them. After just 1 turn there are only 2 3-PGAL molecules, so the 2 molecules continue through the cycle until enough net carbon has been fixed to export one, which will be after 3 cycles.32
6793766806Phase 3 of the Calvin Cycle (Regeneration, Per 3 Carbon)After 3 "turns" from the 3 CO₂ molecules there are 6 3-PGAL molecules present. Of the 6 3-PGAL Molecules produced in the previous phase, one exits to produce glucose, and the other 5 go on to become 3 RuP. 3 ATP is used to convert the 3 RuP molecules into 3 RuBP that accepts CO₂ as it enters into the calvin cycle.33
67939160542 3-PGALThe amount of 3-PGAL molecules it takes to produce one glucose molecule in the calvin cycle.34
6793919528RuBP (Ribulose Diphosphate)This molecule accepts CO₂ that enters the calvin cycle with the help of the enzyme RuBisCO. It is regenerated in phase 3 of the calvin cycle.35
6793945792RuBisCO (RuBP Carboxylase)This enzyme fixes CO₂ that enters into the calvin cycle to RuBP to form an unstable 6-C compound.36
6794030442PGA (Phosohoglycerate)Two of these molecule result when the unstable 6-carbon molecule fixed by RuBisCO breaks apart.37
6794043535DGPA (Diphosphoglycerate)This molecule results when the molecule 3-PGA is phosphorylated by ATP.38
67940518533-PGAL (Glyceraldehyde 3-Phosphate)This molecule results when the molecule DGPA receives e- and H+ molecules from NADPH and loses a phosphate molecule.39
6794086657RuP (Ribulose Phosphate)This molecule results after 3-PGAL is formed and one is either exported or simply continues on to become this molecule. This molecule is phosphorylated by ATP to become RuBP in the regeneration phase of the calvin cycle.40
67941647413 TurnsThe amount of "turns" it takes to make 1 3-PGAL molecule.41
67941681236 TurnsThe amount of "turns" it takes to make 2 3-PGAL molecules (also the amount of turns to make one glucose molecule).42
6794183436PhotorespirationA problem with photosynthesis that occurs when the concentration of O₂ > CO₂ in the leaves. This occurs in dry, hot, and bright conditions. When this process happens, O₂ enters the calvin cycle and is accepted by RuBP instead of CO₂. When this occurs a 5-carbon compound is produced and 1 PGA enters the calvin cycle and a 2-carbon glycolate exits the chloroplast. This decreases productivity of the calvin cycle.43
6794222926C4 Plants (C₄ Plants)This type of plant fixes the problem of photorespiration by fixing CO₂ as a 4-carbon oxaloacetate molecule instead of a 6-carbon compound and also segregates the carbon fixation phase from the rest of the cycle. These types of plants also have a different molecule called PEP that fixes the carbon instead of RuBisCO that has a lower affinity for O₂. Ex. corn, sugarcane44
6794258874MesophyllLocation of carbon fixation in C₄ plants.45
6794272006Bundle-Sheath CellLocation of the rest of the calvin cycle (not fixation) in C₄ plants.46
6794280905CAM Plants (Crassulacean Acid Metabolism Plants)This type of plant fixes the problem of photorespiration by only opening its stomata at night, and keeping them closed in the day. As CO₂ enters the stomata, the concentration of organic acid increases. When the stomata closes, the organic acid is broken down and the CO₂ is released into the calvin cycle. Ex. cactus, pineapple.47
6794314499MesophyllLocation of calvin cycle within CAM plants.48
6794328870Water (Water (H₂O) -> Oxygen (O₂))The substance that is oxidized in photosynthesis.49
6794336984Carbon Dioxide (Carbon Dioxide (CO₂) -> Glucose (C₆H₁₂O₆))The substance that is reduced in photosynthesis.50
6794339405Absorption SpectrumThe amount of light that is absorbed and what light is absorbed.51
6794343285Action SpectrumThe wavelengths that are actually used in photosynthesis.52
6794352134WaterThis molecule's role in linear electron flow is to provide electrons that can be energized by light energy.53
6794361893Water (H₂O), Sunlight, ADP, P, NADP+These are the reactants of the light cycle of photosynthesis.54
6794364089Oxygen (O₂), ATP, NADPHThese are the products of the light cycle of photosynthesis.55
6794400062Carbon Dioxide (CO₂), ATP, NADPHThese are the reactants of the calvin cycle of photosynthesis.56
6794414736Glucose (C₆H₁₂O₆), ADP, P, NADP+These are the products of the calvin cycle of photosynthesis.57
67944360503 Carbon Dioxide (CO₂)For every 3-PGAL exported from the calvin cycle, how many CO₂ molecules enter?58
67944745499 ATPFor every 3-PGAL exported from the calvin cycle, how many ATP molecules are used?59
67944798466 NADPHFor every 3-PGAL exported from the calvin cycle, how many NADPH molecules are used?60
67944876816 Carbon Dioxide (CO₂)For every glucose produced by the calvin cycle, how many CO₂ molecules enter?61
679449764418 ATPFor every glucose produced by the calvin cycle, how many ATP molecules are used?62
679450095312 NADPHFor every glucose produced by the calvin cycle, how many NADPH molecules are used?63
6794576631Electromagnetic SpectrumThe spectrum of visible light.64
6794580342CuticleThe waxy coating on the epidemal surface of a plant that prevents water loss.65

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