Javascript required
Skip to content Skip to sidebar Skip to footer

Campbell Biology 9th Edition Chapter 8 Reading Guide

1794698097 Concept 8.1: An organism's metabolism transforms matter and energy, subject to the laws of thermodynamics ... 0 1794698137 Metabolism The totality of an organism's chemical reactions, consisting of catabolic and anabolic pathways, which manage the material and energy resources of the organism 1 1794698138 Metabolic pathway A series of chemical reactions that either builds a complex molecule (anabolic pathway) or breaks down a complex molecule to simpler molecules (catabolic pathway) 2 1794698139 Catabolic pathway Releases Energy. A metabolic pathway that releases energy by breaking down complex molecules to simpler molecules 3 1794698140 Anabolic pathway Consumes Energy. A metabolic pathway that consumes energy to synthesize a complex molecule from simpler molecules 4 1794698141 Bioenergetics Bioenergetics is the study of how organisms manage their energy resources 5 1794698142 Energy The capacity to cause change, especially to do work (to move matter against an opposing force). 6 1794698143 Kinetic energy Energy of motion 7 1794698144 Heat (thermal) energy Kinetic energy associated with random movement of atoms or molecules 8 1794698145 Potential energy The energy that matter possesses as a result of its location or spatial arrangement (structure) 9 1794698146 Chemical energy Energy available in molecules for release in a chemical reaction; a form of potential energy 10 1794698147 Thermodynamics The study of energy transformations that occur in a collection of matter. 11 1794698148 First law of thermodynamics The principle of conservation of energy; energy can be transferred and transformed, but it cannot be created or destroyed 12 1794698149 Entropy a measure of disorder, or randomness 13 1794698150 Second law of thermodynamics Energy transfer. The principle stating that every energy transfer or transformation increases the entropy of the universe. Usable forms of energy are at least partly converted to heat 14 1794698151 Spontaneous process Without Energy. Spontaneous processes occur without energy input; they can happen quickly or slowly 15 1794698152 What is the second law of thermodynamics? The principle stating that every energy transfer or transformation increases the entropy of the universe. 16 1794698153 What is the first law of thermodynamics? Energy can be transferred and transformed, but it cannot be created or destroyed 17 1794698154 How does the second law of thermodynamics help explain the diffusion of a substance across a membrane? The second law is the trend toward randomization, or increasing entropy. When the concentration of a substance on both sides of a membrane are equal, the distribution is more random than when they are unequal. Diffusion of a substance to a region where it is initially less concentrated INCREASES ENTROPY, making it an energetically favorable (SPONTANEOUS) process. 18 1794698155 Describe the forms of energy found in an apple as it grows on a tree, then falls, then is digested by someone who eats it Potential. Chemical. Kinetic. Thermal. As it sits on the tree, the apple has potential energy because of its position and chemical energy because of its nutrients. As it is falling it has kinetic energy. When eaten and digested, some chemical energy becomes work and the rest is heat. 19 1794698098 If you place a teaspoon of sugar in the bottom of a glass of water, it will dissolve completely over time. Left longer, crystals will reappear. Explain these observations in terms of entropy Sugar crystals are less ordered - more entropy as they dissolve. As the water becomes less ordered - more entropy and evaporates, the sugar becomes more ordered- decrease in entropy, becoming crystals 20 1794698156 Concept 8.2 The free energy change of a reaction tells us whether or not the reaction occurs spontaneously. ... 21 1794698157 Free energy The portion of a biological system's energy that can perform work when temperature and pressure are uniform throughout the system. The change in free energy of a system is calculated by the equation delta G = delta H - T delta S, where delta H is the change in enthalpy (in biological systems, equivalent to total energy), T is the absolute temperature, and delta S is the change in entropy. 22 1794698158 Exergonic reaction Energy is released. A reaction is exergonic if more energy is released than supplied. delta G<0 23 1794698159 Endergonic reaction Energy must be supplied. A reaction is endergonic if more energy is supplied than is released. delta G>0 24 1794698160 Endergonic reaction The reaction will not occur spontaneously delta G>0 25 1794698161 Cellular respiration uses glucose and oxygen, which have high levels of free energy, and releases CO2 and water, which have low levels of free energy. Is cellular respiration spontaneous or not? Cellular Respiration is SPONTANEOUS! 26 1794698162 Cellular respiration uses glucose and oxygen, which have high levels of free energy, and releases CO2 and water, which have low levels of free energy. Is it exergonic or endergonic? Cellular Respiration is an EXERGONIC process 27 1794698163 Cellular respiration uses glucose and oxygen, which have high levels of free energy, and releases CO2 and water, which have low levels of free energy. What happens to the energy released from glucose? The energy released from glucose is used to do work in the cell or is lost as heat 28 1794698164 As we saw in figure 7.20 on page 137, a key process in metabolism is the transport of hydrogen ions (H+) across a membrane to create a concentration gradient. Other processes can result in an equal concentration of H+ on each side. Which situation allows the H+ to perform work on the system? At equilibrium, the H+ concentration is the same and the Hydrogen ions can no no work. When there is an imbalance, or a gradient Hydrogen ions go to work. 29 1794698165 As we saw in figure 7.20 on page 137, a key process in metabolism is the transport of hydrogen ions (H+) across a membrane to create a concentration gradient. Other processes can result in an equal concentration of H+ on each side. Which situation allows the H+ to perform work on the system and how is the answer consistent with what is shown in regards to energy in figure 7.20? Figure 7.20 shows that an energy input via ATP hydrolysis is required to establish a concentration gradient that allows the Hydrogen ions to go to work. 30 1794698166 Glow in the dark necklaces start glowing once activated which usually involves snapping the necklaces in a way that allows two chemicals to react and emit light in the form of chemilluminescence. Is the chemical reaction exergonic or endergonic? The reaction is EXERGONIC because it releases energy in the form of light. 31 1794698167 Concept 8.3 ATP powers cellular work by coupling exergonic reactions to endergonic reactions ... 32 1794698168 Energy coupling In cellular metabolism, the use of energy released from an exergonic reaction drives an endergonic reaction 33 1794698169 ATP Adenosine Triphosphate 34 1794698170 ATP (adenosine triphosphate) An adenine-containing nucleoside triphosphate that releases free energy when its phosphate bonds are hydrolyzed. This energy is used to drive endergonic reactions in cells. 35 1794698171 Phosphorylated intermediate A molecule (often a reactant) with a phosphate group covalently bound to it, making it more reactive (less stable) than the unphosphorylated molecule 36 1794698099 What are the three main types of work that a cell does? Chemical Transport Mechanical 37 1794698172 How does ATP typically transfer energy from ergonic to endergonic reactions in the cell? By Phosphorylating, adding phosphate groups to, other molecules. Exergonic process phosphorylate ADP to regenerate ATP 38 1794698100 Which of the following combinations has more free energy: Glutamic acid + ammnia +ATP or Glutamine + ADP + P1? Explain A set of coupled reactions can transform the first combinations into the second. Since this is an exergonic process overall, Delta G is negative and the first combination must have more energy. 39 1794698173 Considering what we learned in concepts 7.3 and 7.4 (pages 134-136), does figure 8.10a show passive or active transport? Active Transport - the solute is being transported against its concentration gradient 40 1794698174 Concept 8.4 Enzymes Speed Up Metabolic Reactions by Lowering Energy Barriers ... 41 1794698175 Enzyme A macromolecule serving as a catalyst in a chemical agent that increases the rate of a reaction without being consumed by the reaction; most are proteins 42 1794698176 Catalyst A chemical agent that selectively increases the rate of a reaction without being consumed by the reaction 43 1794698177 Activation energy The amount of energy that reactants must absorb before a chemical reaction will start; also called free energy of activation 44 1794698178 Substrate the reactant on which an enzyme works. 45 1794698179 Enzyme-substrate complex a temporary complex formed when an enzyme binds to is substrate molecule(s). 46 1794698180 Active site the specific region of an enzyme that binds the substrate and that forms the pocket in which catalysis occurs 47 1794698181 Induced fit Caused by entry of the substrate, the change in shape of the active site of an enzyme so that it binds more snuggly to the substrate 48 1794698182 Cofactor Any nonprotein molecule or ion that is required for the proper functioning of of an enzyme; can be permanently bound to the active site or may be loosely bound and reversibly, along with the substrate during catalysis. 49 1794698183 Coenzyme an organic molecule serving as a cofactor; in metabolic reactions, most vitamins function as this. 50 1794698184 Competitive inhibitor a substance that reduces the activity of an enzyme by entering the active site in place of the substrate, whose structure it mimics 51 1794698185 Noncompetitive inhibitor a substance that reduces the activity of an enzyme by binding to a location remote from the active site, changing an enzyme's shape so that the active site no longer effectively catalyses the conversion of substrate to product 52 1794698101 Many spontaneous reactions occur very slowly. Why don't all spontaneous reactions occur instantly? While spontaneous reactions are exergonic, if they have a high activation energy that is rarely reached, the rate of reaction could be very slow 53 1794698102 Why do enzymes act only on very specific substrates? Only the specific substrate will fit properly into the active site of an enzyme where the catalysis happens 54 1794698103 Malonate is an inhibitor of the enzyme succinate dehyrogenase. How would you determine whether malonate is a competitive or noncompetitive inhibitor? With malonate present, increase the amount of the normal substrate and determine if the reaction increases, if it does, then you know that malonate is a competitive inhibitor 55 1794698104 In nature, what conditions could lead to natural selection favoring bacteria with enzymes that could break down the fucose-containing disaccharide discussed above? If lactose wasn't present in the environment as a source of food and the fucose-containing disaccharide was available, bacteria that could digest the latter would be better able to grow and multiply than those that could not. 56 1794698186 Concept 8.5 Regulation of Enzyme Activity Helps Control Metabolism ... 57 1794698187 Allosteric regulation The binding of a regulatory molecule to a protein at one site that affects the function of the protein at a different site 58 1794698188 Cooperativity A kind of allosteric regulation whereby a shape change in one subunit of a protein caused by substrate binding is transmitted to all the other subunits, facilitating binding of additional substrate molecules to those subunits 59 1794698189 Feedback inhibition A method of metabolic control in which the end product of a metabolic pathway acts as an inhibitor of an enzyme within that pathway. 60 1794698105 How do an activator and an inhibitor have different effects on an allosterically regulated enzyme? The activator binds and stabilizes he active form of an enzyme, whereas the inhibitor will stabilize the INACTIVE form 61 1794698106 You want to design drug that inhibits a particular enzyme, after research you learn that an enzymes active site is simmilar to that of several other enzymes. What would be a good approach to develop your inhibitor drug? An inhibitor that binds to the active site of the enzyme you want to inhibit could also bind to and block the enzymes with similar structures, causing significant side effects. For this reason you would be better off choosing to screen chemical compounds that bind allosterically to the enzyme in question because allosteric regulatory sites are less likely to share similarity with other enzymes. 62 1794698107 Define Metabolism The totality of an organism's chemical reactions, consisting of catabolic and anabolic pathways, which manage the material and energy resources of the organism 63 1794698108 Define Energy The capacity to cause change, especially to do work (to move matter against an opposing force). 64 1794698109 List and describe 5 forms of energy Kinetic Potential Chemical Heat/Thermal 65 1794698110 What is a catalyst? A chemical agent that selectively increases the rate of a reaction without being consumed by the reaction. 66 1794698111 Distinguish between anabolic and catabolic reactions? Anabolic is building a molecule by consuming energy and catabolic is breaking it down to release energy 67 1794698112 Word Roots: allo- different (allosteric site: a specific receptor site on some part of an enzyme molecule remote from the active site) 68 1794698113 Word Roots: ana- up (anabolic pathway: a metabolic pathway that consumes energy to build complex molecules from simpler ones) 69 1794698114 Word Roots: bio- ife (bioenergetics: the study of how organisms manage their energy resources) 70 1794698115 Word Roots: cata- down (catabolic pathway: a metabolic pathway that releases energy by breaking down complex molecules into simpler ones) 71 1794698116 Word Roots: endo- within (endergonic reaction: a reaction that absorbs free energy from its surroundings) 72 1794698117 Word Roots: ex- out (exergonic reaction: a reaction that proceeds with a net release of free energy) 73 1794698118 Word Roots: kinet- movement (kinetic energy: the energy of motion) 74 1794698119 Word Roots: therm- heat (thermodynamics: the study of the energy transformations that occur in a collection of matter) 75 1794698120 Metabolic pathway A series of chemical reactions that either builds a complex molecule (anabolic pathway) or breaks down a complex molecule to simpler molecules (catabolic pathway). 76 1794698190 Define how an enzyme works An enzyme serves as a biological catalyst, increasing the rate of a reaction without being changed into a different molecule. An enzyme does not add energy to a reaction; instead, it speeds up a reaction by lowering the energy barrier. 77 1794698121 Molecule Two or more atoms held together by covalent bonds. 78 1794698191 Substrate The reactant on which an enzyme works. 79 1794698122 Name three factors that affect enzyme action pH Temperature Substrate Concentration 80 1794698123 What does it mean when an enzyme is denatured? An enzyme is said to be denatured when it loses its functional shape. 81 1794698192 What does Gibbs Free Energy Measure? Chemical Energy 82 1794698193 Give the equation for Gibbs Free Energy Delta G equals delta H - T delta S 83 1794698124 Explain the Gibbs Free Energy Equation A change in free energy is equal to a change in heat content minus a change in Temperature times Randomness 84 1794698194 The process of stabilizing the structure of an enzyme in its active form by the binding of a molecule is an example of allosteric regulation 85 1794698125 What is meant by the "induced fit" of an enzyme? The enzyme changes its shape slightly as the substrate binds to it 86 1794698126 How do enzymes lower activation energy? By locally concentrating the reactants. One of the ways enzymes work is to increase the concentrations of reactants at a single place. 87 1794698127 What do the sign and magnitude of the ΔG of a reaction tell us about the speed of the reaction? Neither the sign nor the magnitude of ΔG have anything to do with the speed of a reaction. 88 1794698128 If an enzyme is added to a solution where its substrate and product are in equilibrium, what will occur? Nothing; the reaction will stay at equilibrium. 89 1794698129 Some bacteria are metabolically active in hot springs because their enzymes have high optimal temperatures. 90 1794698130 If an enzyme in solution is saturated with substrate, the most effective way to obtain a faster yield of products is to add more of the enzyme. 91 1794698131 Which of the following metabolic processes can occur without a net influx of energy from some other process? ADP +(P) i → ATP + H20 or C6H12O6 + 6 O2 → 6 CO2 + 6 H2O C6H12O6 + 6 O2 → 6 CO2 + 6 H2O 92 1794698132 Most cells cannot harness heat to perform work because temperature is usually uniform throughout a cell. 93 1794698133 Choose the pair of terms that correctly completes this sentence: Catabolism is to anabolism as _______ is to _______. xergonic; endergonic 94 1794698134 closed system A system in which energy, but not matter, is exchanged with its surroundings. 95 1794698135 open system A system in which both energy and matter are exchanged with the surroundings. 96 1794698136 kelvin A unit of absolute temperature and symbolized as K. Formerly known as degree Kelvin. 97 1794698195 allosteric inhibition The process in which an enzyme's activity is changed because of binding to the allosteric site., two active sites; one site for inhibitor, changes shape of other active site to become inactive 98

Campbell Biology 9th Edition Chapter 8 Reading Guide

Source: https://course-notes.org/flashcards/campbell_biology_ninth_edition_chapter_8_an_introduction_to_metabolism_flashcards_0