Term
| What is activation energy? |
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Definition
| The initial amount of energy needed to start a chemical reaction. |
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Term
| What is the transition state? |
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Definition
| The summit of the reaction when the molecules are in an unstable state. |
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Term
| How do enzymes accelerate reactions and lower activation energy requirements? |
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Definition
| They provide an environment for the chemical reaction to proceed. |
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Term
| What is a cofactor? A coenzyme? |
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Definition
| A nonprotein enzyme helper. Coenzymes are organic cofactors for enzymes. |
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Term
| What is a competitive inhibitor? |
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Definition
| An imitator of a substrate that binds to the active site of an enzyme, competing with the substrate. |
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Term
| What is a noncompetitive inhibitor? |
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Definition
| An inhibitor that binds to another part of an enzyme that changes the function. |
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Term
| What is a distinguishing characteristic of living things from nonliving matter? |
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Definition
| The ability of organisms to reproduce. |
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Term
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Definition
| A cell's endowment of DNA, genetic information. |
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Term
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Definition
| A complex of DNA and protein that condenses during cell division. |
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Term
| Where are chromatids connected? |
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Definition
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Term
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Definition
| Sex cells have a reduction in chromosome number, yield 4 nonidentical daughter cells, and each with half the chromosomes of the parent. |
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Term
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Definition
| The chromosomes are tighttly packed, chromatids are joined, and mitotic spindle begins to form. |
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Term
| What occurs in prometaphase? |
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Definition
| The nuclear envelope fragments, the microtubules from the spindle interact with the chromosomes and the chromatids contain a kinetochore. |
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Term
| What occurs in metaphase? |
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Definition
| Sister chromatids are arranged at the metaphase plate. |
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Term
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Definition
| The centromeres divide separating the sister chromatids which are pulled toward the poles. |
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Term
| What occurs int telophase? |
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Definition
| Daughter nuclei begin to form at the 2 poles and nuclear envelopes begin to arise. |
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Term
| What facilitates cytokinesis? |
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Definition
| Actin microfilaments that form a contractile ring. |
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Term
| What type of cell division do bacteria use? |
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Definition
| Binary fission- the bacterial chromosome, circular DNA, repicates and the two daughter chromosomes separate. |
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Term
| What regulate the progress through the cell cycle? |
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Definition
| Molecules and enzymes in the cytoplasm. |
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Term
| How many major chechpoints are there in the cell cycle? Which is typically the most important? |
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Definition
| There are three (G1, G2, M). G1 is typically the most important. |
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Term
| What are catabolic pathways? |
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Definition
| They break down complex molecules into simpler compounds during a process that releases energy. |
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Term
| What do anabolic pathways do? |
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Definition
| They build complicated molecules from simpler ones during a process that consumes energy. |
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Term
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Definition
| The study of energy transformations and life is subject to the laws of thermodynamics. |
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Term
| What is the first law of thermodynamics? |
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Definition
| Energy can be transferred and transformed but cannot be created or destroyed. |
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Term
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Definition
| The quantity of disorder or randomness. The more random, the greater the entropy. |
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Term
| What is the second law of thermodynamics? |
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Definition
| Every energy transfer or transformation increases the entropy of the universe. Order may increase locally, however the universe tends ttoward randomness. |
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Term
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Definition
| Energy that can do work under cellular conditions (constant temperature and pressure). |
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Term
| What dictates spontaneity of a reaction? Why is this important? |
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Definition
| Free energy change of a reaction dictates spontaneity. Spontaneous changes do not require energy which is preferred for cellular reactions. |
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Term
| What is the formula for the change in free energy? |
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Definition
| Change in free energy = enthalpy change - T(change in entropy). |
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Term
| What is the importance of free energy change? |
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Definition
| When free energy decreases, stability of a system increases. When free energy change is negative, the more work a spontaneous process can perform. |
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Term
| Are exergonic reactions spontaneous? |
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Definition
| Yes, exergonic reactions are spontaneous, and endergonic are not spantaneous (positive free energy change). |
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Term
| Do cells maintain a system of equilibrium? |
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Definition
| No, cells tend toward disequilibrium because they are open system. |
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Term
| List and define the three kinds of work that cells do. |
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Definition
| Mechanical: the beating of cilia/flagella or contracting muscles. Transport: pumping substances across membranes. Chemical: Driving endergonic reactions such as synthesis of polymers from monomers. |
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Term
| When is energy released from ATP? |
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Definition
| When the terminal phosphate bond is broken. |
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Term
| How do cells make reactions favorable? |
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Definition
| By coupling ATP hydrolysis with other reactions. |
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Term
| How do enzymes regulate reactions in metabolic pathways? |
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Definition
| By bond breaking and forming. |
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Term
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Definition
| Catalyzes the hydrolysis of sucrose (breaking of the bond between glucose and fructose). |
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Term
| What is allosteric regulation? |
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Definition
| Protein's function at one site is affected by binding of a regulatory molecule at another site. |
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Term
| What do allosteric enzymes do? |
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Definition
| Change shape when regulatory molecules bind to specific site affecting function. |
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Term
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Definition
| A form of allosteric regulation that can amplify enzyme activity. |
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Term
| What is feedback inhibition? Why is this important? |
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Definition
| The end product of a metabolic pathway feeds back upon itself and shuts down the pathway. It prevents a cell from wasting chemical energy. |
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Term
| How does energy enter and exit most ecosystems? |
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Definition
| Enters as sunlight, leaves as heat. |
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Term
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Definition
| Partial degradation of sugars that occurs in the absence of oxygen. |
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Term
| What dictates catabolic pathways' ability to yield energy? |
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Definition
| The ease in which they transfer electrons. |
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Term
| What are redox reactions? |
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Definition
| The transfer of electrons (energy) from one reactant to another by oxidation and reduction. |
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Term
| What happens in oxidation? |
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Definition
| A substance loses electrons (is oxidized). |
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Term
| What happens in reduction? |
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Definition
| A substances gains electrons (is reduced). |
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Term
| What is an example of a redox reaction? |
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Definition
| The formation of table salt. Sodium oxidized, chlorine reduced. |
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Term
| What is being oxidized and reduced in cellular respiration? |
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Definition
| Glucose is oxidized. Oxygen is reducd. |
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Term
| What does dehydrogenase do? |
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Definition
| Removes 2 hydrogen atoms from glucose and transfers 2 electrons and one proton to Nad+ during cellular respiration. |
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Term
| Where is the electron transport chain located? |
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Definition
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Term
| How does the electron transport chain "break the fall" of electrons? What does it do with the energy resulting from this process? |
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Definition
| By passing them in a controlled series of steps. The energy from electron transfer is used make ATP. |
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Term
| What occurs at the lower end of the electron transport chain? |
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Definition
| Oxygen captures the electrons along with hydrogen to form H2O. |
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Term
| What is respiration a cumulative function of? |
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Definition
| Glycolysis, CAC, and oxy.phos. |
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Term
| Where do each of the three parts of respiration occur? |
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Definition
| Glycolysis occurs in the cytoplasm, while Krebs and Oxy take place in the mitochondria. |
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Term
| Which parts of respiration generate ATP by substrate-level phosphorylation? |
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Definition
| Glycolysis and CAC. Oxyphos is oxidatize phosphorylation. |
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Term
| What occurs in substrate-level phosphorylation? |
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Definition
| An enzyme transfers a phosphate group from an organic structure to ADP, forming ATP. |
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Term
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Definition
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Term
| What two phases are a part of glycolysis? |
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Definition
| Energy investment phase and the energy payoff phase. |
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Term
| What occurs between glycolysis and CAC? |
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Definition
| Pyruvate is transported and cnverted to acetyl CoA. |
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Term
| What does the CAC produce per molecule of glucose? |
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Definition
| 2FADH, 6NADH, 2ATP, 4CO2. |
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Term
| What does the transport between glycolysis and CAC yield per molecule of glucose? |
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Definition
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|
Term
| What accounts for the majority of energy extracted from food? |
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Definition
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Term
| What are NADH and FADH's functions with respect to the electron transport chain? Why is this significant? |
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Definition
| They donate electrons. This powers ATP synthesis via oxidative phosphorylation. |
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Term
| Do NADH and FADH lose or gain energy in the electron transport chain? |
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Definition
| They lose energy until the electrons are passed to oxygen, forming water. |
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Term
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Definition
| ATP synthase is a large protein complex imbedded in the mitochondrial wall and is the enzyme that synthesizes ATP. |
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Term
| What is the purpose of the H+ gradient created in oxidative phosphorylation? |
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Definition
| It stores energy and drives chemiosmosis (through ATP synthase). |
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Term
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Definition
| An energy-coupling mechanism that uses energy in the form of a H+ gradient across a membrane to drive cellular work and the formation of ATP. |
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Term
| What sequence does most energy flow in during respiration? |
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Definition
| Glucose to NADH to electron transport chain to proton-motive force to ATP. |
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Term
| What is the yield of one molecule of glucose during glycolysis and the CAC? |
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Definition
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|
Term
| How much ATP is generated from glucose and what is the breakdown? |
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Definition
| 34 from oxyphos, 4 from substrate level. 36-38 overall. |
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|
Term
| What percent of energy in a glucose molecule is transferred to ATP during cellular respiration? |
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Definition
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|
Term
| What is the importance of electronegative oxygen? |
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Definition
| Without is, oxyphos stops. |
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Term
| What does fermentation do? |
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Definition
| It enables some cells to produce ATP without use of oxygen. It can generate ATP from glucose by substrate-level phosphorylation as long as there is a supply of NAD+ to accept electrons. |
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Term
| What is pyruvate converted to in alcohol and lactic acid fermentation? |
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Definition
| In alcohol fermentation, it is converted to ehtanol in two steps, releasing CO2 in one of them. In lactic acid fermentation, pyruvate is reduced directly to NADH to form lactate as a waste product. |
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Term
| What is the difference between fermentation and cellular respiration? What is the same? |
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Definition
| They both use glycolysis to oxidize glucose and other organic fuels to pyruvate but respiration produces more ATP. |
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Term
| What controls cellular respiration? |
|
Definition
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Term
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Definition
| The process that converts solar energy into chemical energy and helps nourish the biosphere. |
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Term
| What do plant chloroplasts use photosynthesis for? |
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Definition
| Capturing light energy from the sun and converting it into stored sugars and organic molecules. |
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Term
| What are the two types of autotrophs? |
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Definition
| Photoautotrophs or chemoauthotrophs? |
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Term
| What type of autotroph are plants? |
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Definition
| Plants are photoautotrophs because they use the energy of sunlight to make organic molecules from water and CO2. |
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Term
| What are the major sites of photosynthesis? What does leaf color come from? |
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Definition
| Leaves are the major site of photosynthesis. The color comes fro the chlorophyll, a green pigments in the chloroplasts. |
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Term
|
Definition
| Stomata are the pores in the leaf through which O2 and CO2 leave and enter. |
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Term
|
Definition
| The organelles in which photosynthesis occurs |
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Term
|
Definition
| The aqueous space in chloroplasts. |
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|
Term
| Where are thylakoids and grana contained? |
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Definition
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|
Term
| What type of reaction is photosynthesis? |
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Definition
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|
Term
| Is photosynthesis a redox process? |
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Definition
| Yes, water is oxidized and CO2 is reduced. |
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Term
| What are photo reactions that occur in photosynthesis? |
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Definition
| Occurring in the grana, they split water, release oxygen, produce ATP, and form NADPH. |
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Term
| What is the Calvin Cycle? |
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Definition
| It occurs in the stroma, forms sugar from Carbon dioxide, uses ATP for energy, and NADPH for reducing power. |
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Term
| What form of chemical energy do light reactions convert solar energy to? |
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Definition
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|
Term
| What is a pigment? Give an example. |
|
Definition
| Substances that absorb visible light and reflect the light that we see. An example is chlorophyl A. |
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|
Term
| What is an action spectrum of pigment? |
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Definition
| It profiles the relative effectiveness of different wavelengths of radiation in driving photosynthesis. |
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|
Term
| What happens when a pigment absorbs light? |
|
Definition
| Its electrons become unstable and it goes from a ground state to an excited state that releases heat energy and sometimes fluorescence. |
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|
Term
| What are chlorophyll and other proteins organized into? |
|
Definition
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|
Term
| What do light-harvesting complexes do? |
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Definition
| They funnel energy of photons of light to the reaction center. |
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|
Term
| What does the reaction-center chlorophyll do? |
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Definition
| They absorb energy and as the electrons "fall" to a lower energy level, their energy is harnessed to produce ATP. |
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|
Term
| Do chloroplasts or mitochondria use the H+ gradient? |
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Definition
| Both use it. Both use ATP synthase and proton motive force to make ATP. |
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|
Term
| What does the Calvin Cycle do? |
|
Definition
| ATP and NADPH to convert CO2 to sugar. |
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|
Term
| Where does the Calvin Cyle occur? What three phases does it have? |
|
Definition
| It occurs in the stroma. The three phases are Carbon fixation, reduction, regeneration of the CO2 acceptor. |
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|
Term
| What does one turn of the CAC yield? |
|
Definition
|
|
Term
| Two molecules of glucose enter cellular respiration. At the end of CAC, how much ATP, NADH, FADH will be made? |
|
Definition
|
|
Term
| What is the significance of the NADH/FADH produced in the CAC? |
|
Definition
| It is taken to the electron transport chain, and used to eventually make ATP via ATP synthase. |
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|
Term
| What is an allosteric activator? An allosteric inhibitor? |
|
Definition
| Activator binds to an enzyme and increases the speed of reaction, inhibitor stops the function. Example of an activator is glucose for hexokinase. Example of an inhibitor is ATP for hexokinase. |
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|
Term
| What are the two parts of oxidative phosphorylation? |
|
Definition
| Electron transport chain and chemiosmosis. |
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|
Term
| What is produced via a light reaction? |
|
Definition
|
|
Term
| What occurs in the Calvin Cycle? |
|
Definition
| It takes in ATP and NADPH and produces sugar, ADP, and NADP. |
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|
Term
| What is the difference between catabolic and anabolic? |
|
Definition
| Catabolic (such as cellular respiration) makes ATP as a result. Anabolic takes ATP and makes something from it (such as photosynthesis). |
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|
Term
| Are living systems closed? |
|
Definition
| No, living systems are open because they interact with the things around them, expending and accepting energy. |
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|
Term
| What does dehydrogenase do? |
|
Definition
| Helps make NADH by adding the H. |
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|
Term
| Where does the Calvin Cycle occur? |
|
Definition
|
|
Term
| Where do light reactions of photosynthesis occur? |
|
Definition
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