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| 15885248254 | Which term most precisely describes the cellular process of breaking down large molecules into smaller ones? | catabolism | 0 | |
| 15885248255 | Which of the following is (are) true for anabolic pathways? | They consume energy to build up polymers from monomers. | 1 | |
| 15885248256 | Which of the following is a statement of the first law of thermodynamics? | Energy cannot be created or destroyed. | 2 | |
| 15885248257 | For living organisms, which of the following is an important consequence of the first law of thermodynamics? | The organism ultimately must obtain all of the necessary energy for life from its environment. | 3 | |
| 15885248258 | Living organisms increase in complexity as they grow, resulting in a decrease in the entropy of an organism. How does this relate to the second law of thermodynamics? | As a consequence of growing, organisms cause a greater increase in entropy in their environment than the decrease in entropy associated with their growth. | 4 | |
| 15885248259 | Whenever energy is transformed, there is always an increase in the | entropy of the universe | 5 | |
| 15885248260 | Which of the following statements is a logical consequence of the second law of thermodynamics? | Every chemical reaction must increase the total entropy of the universe | 6 | |
| 15885248261 | Which of the following statements is representative of the second law of thermodynamics? | Cells require a constant input of energy to maintain their high level of organization | 7 | |
| 15885248262 | Which of the following types of reactions would decrease the entropy within a cell? | anabolic reactions | 8 | |
| 15885248263 | The organization of organisms has become increasingly complex with time. This statement | is consisted with the second law of thermodynamics | 9 | |
| 15885248264 | Which of the following is an example of potential rather than kinetic energy? | a molecule of glucose | 10 | |
| 15885248265 | Which of the following is considered an open system? | an organism | 11 | |
| 15885248266 | Which of the following is true of metabolism in its entirety? | Metabolism consists of all the energy transformation reactions in an organism | 12 | |
| 15885248267 | The mathematical expression for the change in free energy of a system is △G =△H-T△S. Which of the following is (are) correct? | ΔG is the change in free energy | 13 | |
| 15885248268 | What is the change in free energy of a system at chemical equilibrium? | no net change | 14 | |
| 15885248269 | Which of the following is true for all exergonic reactions? | The reaction proceeds with a net release of free energy | 15 | |
| 15885248270 | Chemical equilibrium is relatively rare in living cells. Which of the following could be an example of a reaction at chemical equilibrium in a cell? | a chemical reaction in which both the reactants and products are not being produced or used in any active metabolic pathway | 16 | |
| 15885248271 | Which of the following shows the correct changes in thermodynamic properties for a chemical reaction in which amino acids are linked to form a protein? | +ΔH, -ΔS, +ΔG | 17 | |
| 15885248272 | When glucose monomers are joined together by glycosidic linkages to form a cellulose polymer, the changes in free energy, total energy, and entropy are as follows: | +ΔG, +ΔH, -ΔS | 18 | |
| 15885248273 | A chemical reaction that has a positive △G is correctly described as | endergonic | 19 | |
| 15885248274 | Which of the following best describes enthalpy (H)? | the heat content of a chemical system | 20 | |
| 15885248275 | Why is ATP an important molecule in metabolism? | It provides energy coupling between exergonic and endergonic reactions. | 21 | |
| 15885248276 | When 10,000 molecules of ATP are hydrolyzed to ADP and Pi in a test tube, about twice as much heat is liberated as when a cell hydrolyzes the same amount of ATP. Which of the following is the best explanation for this observation? | Reactant and product concentrations in the test tube are different from those in the cell. | 22 | |
| 15885248277 | Which of the following is most similar in structure to ATP? | an RNA nucleotide | 23 | |
| 15885248278 | What term is used to describe the transfer of free energy from catabolic pathways to anabolic pathways? | energy coupling | 24 | |
| 15885248279 | Which of the following statements is true concerning catabolic pathways? | They supply energy, primarily in the form of ATP, for the cell's work. | 25 | |
| 15885248280 | When chemical, transport, or mechanical work is done by an organism, what happens to the heat generated? | It is lost to the environment | 26 | |
| 15885248281 | When ATP releases some energy, it also releases inorganic phosphate. What purpose does this serve (if any) in the cell? | The phosphate may be incorporated into any molecule that contains phosphate. | 27 | |
| 15885248282 | A number of systems for pumping ions across membranes are powered by ATP. Such ATP- powered pumps are often called ATPases although they don't often hydrolyze ATP unless they are simultaneously transporting ions. Because small increases in calcium ions in the cytosol trigger a number of different intracellular reactions, cells keep the cytosolic calcium concentration quite low under normal conditions, using ATP-powered calcium pumps. For example, muscle cells transport calcium from the cytosol into the membranous system called the sarcoplasmic reticulum (SR). If a resting muscle cell's cytosol has a free calcium ion concentration of 10-7 while the concentration in the SR is 10-2, then how is the ATPase acting? | ATPase activity must be pumping calcium from the cytosol to the SR against the concentration gradient. | 28 | |
| 15885248283 | What must be the difference (if any) between the structure of ATP and the structure of the precursor of the A nucleotide in RNA? | There is no difference. | 29 | |
| 15885248284 | Which of the following statements is (are) true about enzyme-catalyzed reactions? | The reaction is faster than the same reaction in the absence of the enzyme. | 30 | |
| 15885248285 | How can one increase the rate of a chemical reaction? | add a catalyst | 31 | |
| 15885248286 | Sucrose is a disaccharide, composed of the monosaccharides glucose and fructose. The hydrolysis of sucrose by the enzyme sucrase results in | breaking the bond between glucose and fructose and forming new bonds from the atoms of water | 32 | |
| 15885248287 | Reactants capable of interacting to form products in a chemical reaction must first overcome a thermodynamic barrier known as the reaction's | activation energy | 33 | |
| 15885248288 | A solution of starch at room temperature does not readily decompose to form a solution of simple sugars because | the activation energy barrier for this reaction cannot be surmounted. | 34 | |
| 15885248289 | Which of the following statements regarding enzymes is true? | Enzymes increase the rate of a reaction by lowering the activation energy barrier | 35 | |
| 15885248290 | During a laboratory experiment, you discover that an enzyme-catalyzed reaction has a △G of -20 kcal/mol. If you double the amount of enzyme in the reaction, what will be the △G for the new reaction? | -20 kcal/mol | 36 | |
| 15885248291 | The active site of an enzyme is the region that | is involved in the catalytic reaction of the enzyme | 37 | |
| 15885248292 | According to the induced fit hypothesis of enzyme catalysis, which of the following is correct? | The binding of the substrate changes the shape of the enzyme's active site | 38 | |
| 15885248293 | Which curve represents the behavior of an enzyme taken from a bacterium that lives in hot springs at temperatures of 70°C or higher? | curve 3 | 39 | |
| 15885248294 | Which curve was most likely generated from analysis of an enzyme from a human stomach where conditions are strongly acid? | curve 4 | 40 | |
| 15885248295 | Which curve was most likely generated from an enzyme that requires a cofactor? | It is not possible to determine whether an enzyme requires a cofactor from these data. | 41 | |
| 15885248296 | Increasing the substrate concentration in an enzymatic reaction could overcome which of the following? | competitive inhibition | 42 | |
| 15885248297 | Which of the following is true of enzymes? | Enzymes increase the rate of chemical reaction by lowering activation energy barriers | 43 | |
| 15885248298 | Zinc, an essential trace element for most organisms, is present in the active site of the enzyme carboxypeptidase. The zinc most likely functions as a(n) | cofactor necessary for enzyme activity | 44 | |
| 15885248299 | Based on this information, which of the following is correct? | Succinate is the substrate, and fumarate is the product | 45 | |
| 15885248300 | What is the purpose of using malonic acid in this experiment? | it is a competitive inhibitor | 46 | |
| 15885248301 | Which of the following represents the △G of the reaction? | d | 47 | |
| 15885248302 | Which of the following would be the same in an enzyme-catalyzed or noncatalyzed reaction? | d | 48 | |
| 15885248303 | Which of the following represents the difference between the free-energy content of the reaction and the free-energy content of the products? | d | 49 | |
| 15885248304 | Which of the following represents the activation energy required for the enzyme-catalyzed reaction? | b | 50 | |
| 15885248305 | Which of the following represents the activation energy required for a noncatalyzed reaction? | c | 51 | |
| 15885248306 | Assume that the reaction has a △G of -5.6 kcal/mol. Which of the following would be true? | The reaction would result in an increase in entropy (S) and a decrease in the total energy content (H) of the system | 52 | |
| 15885248307 | In order to attach a particular amino acid to the tRNA molecule that will transport it, an enzyme, an aminoacyl-tRNA synthetase, is required, along with ATP. Initially, the enzyme has an active site for ATP and another for the amino acid, but it is not able to attach the tRNA. What must occur in order for the final attachment to occur? | the binding of the first two molecules must cause a 3-dimensional change that opens another active site on the enzyme | 53 | |
| 15885248308 | Competitive inhibitors block the entry of substrate into the active site of an enzyme. On which of the following properties of an active site does this primarily depend? | the ability of an enzyme to form a template for holding and joining molecules | 54 | |
| 15885248309 | Which of the following is likely to lead to an increase in the concentration of ATP in a cell? | an increase in a cell's catabolic activity | 55 | |
| 15885248310 | When you have a severe fever, what may be a grave consequence if this is not controlled? | change in the tertiary structure of your enzymes | 56 | |
| 15885248311 | How does a noncompetitive inhibitor decrease the rate of an enzyme reaction? | by changing the shape of the enzyme's active site | 57 | |
| 15885248312 | The mechanism in which the end product of a metabolic pathway inhibits an earlier step in the pathway is known as | feedback inhibition | 58 | |
| 15885248313 | Which of the following statements describes enzyme cooperativity? | A substrate molecule bound to an active site of one subunit promotes substrate binding to the active site of other subunits. | 59 | |
| 15885248314 | Which of the following is the most correct interpretation of the figure? | ATP is a molecule that acts as an intermediary to store energy for cellular work | 60 | |
| 15885248315 | In coupled reactions, in which direction would the endergonic reaction be driven relative to the clockwise direction of the ATP reaction above and shown in the figure? | it would be shown in a clockwise direction at the top of the figure | 61 | |
| 15885248316 | Some enzymatic regulation is allosteric. In such cases, which of the following would usually be found? | an enzyme with more than one subunit | 62 | |
| 15885248317 | Which of the following is an example of cooperativity? | a molecule binding at one unit of a tetramer, allowing faster binding at each of the other three | 63 | |
| 15885248318 | Among enzymes, kinases catalyze phosphorylation, while phosphatases catalyze removal of phosphate(s). A cell';s use of these enzymes can therefore function as an on-off switch for various processes. Which of the following is probably involved? | the change in a protein's charge leading to a conformational change | 64 | |
| 15885248319 | Besides turning enzymes on or off, what other means does a cell use to control enzymatic activity? | localization of enzymes into specific organelles or membranes | 65 | |
| 15885248320 | An important group of peripheral membrane proteins are enzymes, such as the phospholipases that attack the head groups of phospholipids leading to the degradation of damaged membranes. What properties must these enzymes exhibit? | water solubility | 66 |
