Photosynthesis
Campbell 7e
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| 580518684 | absorption spectrum | The range of a pigment's ability to absorb various wavelengths of light. | |
| 580518685 | action spectrum | A profile of the relative performance of different wavelengths of light. | |
| 580518686 | autotroph | An organism that obtains organic food molecules without eating other organisms or substances derived from other organisms; use energy from the sun or oxidation of inorganic substances to make organic molecules from inorganic ones. | |
| 580518687 | bundle-sheath cell | A type of photosynthetic cell arranged into tightly packed sheaths around the veins of a leaf. | |
| 580518688 | C3 plant | A plant that uses the Calvin cycle for the initial steps that incorporate CO2 into organic material, forming a three-carbon compound as the first stable intermediate. | |
| 580518689 | C4 plant | A plant that prefaces the Calvin cycle with reactions that incorporate CO2 into four-carbon compounds, the end product of which supplies CO2 for the Calvin cycle. | |
| 580518690 | Calvin cycle | The second of two major stages in photosynthesis (following the light reactions), involving atmospheric CO2 fixation and reduction of the fixed carbon into carbohydrate. | |
| 580518691 | CAM plant | A plant that uses crassulacean acid metabolism, an adaptation for photosynthesis in arid conditions, first discovered in the family Crassulaceae. Carbon dioxide entering open stomata during the night is converted into organic acids, which release CO2 for the Calvin cycle during the day, when stomata are closed. | |
| 580518692 | carbon fixation | The incorporation of carbon from CO2 into an organic compound by an autotrophic organism (a plant, another photosynthetic organism, or a chemoautotrophic bacterium). | |
| 580518693 | carotenoid | An accessory pigment, either yellow or orange, in the chloroplasts of plants. By absorbing wavelengths of light that chlorophyll cannot, ___ broaden the spectrum of colors that can drive photosynthesis. | |
| 580518694 | chlorophyll | A green pigment located within the chloroplasts of plants. can participate directly in the light reactions, which convert solar energy to chemical energy. | |
| 580518695 | chlorophyll a | A type of blue-green photosynthetic pigment that participates directly in the light reactions. | |
| 580518696 | chlorophyll b | A type of yellow-green accessory photosynthetic pigment that transfers energy to chlorophyll a. | |
| 580518697 | cyclic electron flow | A route of electron flow during the light reactions of photosynthesis that involves only photosystem I and that produces ATP but not NADPH or oxygen. | |
| 580518698 | electromagnetic spectrum | The entire spectrum of radiation ranging in wavelength from less than a nanometer to more than a kilometer. | |
| 580518699 | glyceraldehyde-3-phosphate (G3P) | The carbohydrate produced directly from the Calvin cycle. | |
| 580518700 | heterotroph | An organism that obtains organic food molecules by eating other organisms or their by-products. | |
| 580518701 | light reactions | The steps in photosynthesis that occur on the thylakoid membranes of the chloroplast and that convert solar energy to the chemical energy of ATP and NADPH, evolving oxygen in the process. | |
| 580518702 | light-harvesting complex | Surrounds the reaction center in a photosystem, and consists of pigment molecules (which may include chlorophyll a chlorophyllb, and carotenoids) bound to particular proteins. | |
| 580518703 | mesophyll | The ground tissue of a leaf, sandwiched between the upper and lower epidermis and specialized for photosynthesis. | |
| 580518704 | mesophyll cell | A loosely arranged photosynthetic cell located between the bundle sheath and the leaf surface. | |
| 580518705 | NADP+ | An acceptor that temporarily stores energized electrons produced during the light reactions. | |
| 580518706 | noncyclic electron flow | A route of electron flow during the light reactions of photosynthesis that involves both photosystems and produces ATP, NADPH, and oxygen. The net electron flow is from water to NADP+. | |
| 580518707 | PEP carboxylase | An enzyme that adds carbon dioxide to phosphoenolpyruvate (PEP) to form oxaloacetate. | |
| 580518708 | photoautotroph | An organism that harnesses light energy to drive the synthesis of organic compounds from carbon dioxide. | |
| 580518709 | photon | A quantum, or discrete amount, of light energy. | |
| 580518710 | photophosphorylation | The process of generating ATP from ADP and phosphate by means of a proton-motive force generated by the thylakoid membrane of the chloroplast during the light reactions of photosynthesis. | |
| 580518711 | photorespiration | A metabolic pathway that consumes oxygen, releases carbon dioxide, generates no ATP, and decreases photosynthetic output; generally occurs on hot, dry, bright days, when stomata close and the oxygen concentration in the leaf exceeds that of carbon dioxide. | |
| 580518712 | photosynthesis | The conversion of light energy to chemical energy that is stored in glucose or other organic compounds; occurs in plants, algae, and certain prokaryotes. | |
| 580518713 | photosystem | The light-harvesting unit in photosynthesis, located on the thylakoid membrane of the chloroplast and consisting of the antenna complex, the reaction-center chlorophyll a, and the primary electron acceptor. There are two types of photosystems, I and II; they absorb light best at different wavelengths. | |
| 580518714 | photosystem I | One of two light-harvesting units of a chloroplast's thylakoid membrane; it uses the P700 reaction-center chlorophyll. | |
| 580518715 | photosystem II | One of two light-harvesting units of a chloroplast's thylakoid membrane; it uses the P680 reaction-center chlorophyll. | |
| 580518716 | primary electron acceptor | A specialized molecule sharing the reaction center with the chlorophyll a molecule; it accepts an electron from the chlorophyll a molecule. | |
| 580518717 | reaction center | The chlorophyll a molecule and the primary electron acceptor in a photosystem; they trigger the light reactions of photosynthesis. The chlorophyll donates an electron, excited by light energy, to the primary electron acceptor, which passes an electron to an electron transport chain. | |
| 580518718 | rubisco | Ribulose carboxylase, the enzyme that catalyzes the first step of the Calvin cycle (the addition of CO2 to RuBP, or ribulose bisphosphate). | |
| 580518719 | spectrophotometer | An instrument that measures the proportions of light of different wavelengths absorbed and transmitted by a pigment solution. | |
| 580518720 | stroma | The fluid of the chloroplast surrounding the thylakoid membrane; involved in the synthesis of organic molecules from carbon dioxide and water. | |
| 580518721 | thylakoid | A flattened membrane sac inside the chloroplast, used to convert light energy to chemical energy. | |
| 580518722 | visible light | That portion of the electromagnetic spectrum detected as various colors by the human eye, ranging in wavelength from about 380 nm to about 750 nm. | |
| 580518723 | wavelength | The distance between crests of waves, such as those of the electromagnetic spectrum. |
