HW#2 Spring 2015 Chpts 7-9Chpt 7: 1. Which of the following eukaryotic organelles/cell components is/are surrounded by a double membrane structure?A. nucleus D. all of the above.B. mitochondria E. Both A & B; but not C.C. chloroplasts2. Which cell structure-function is mismatched?A. nucleolus—ribosomal subunit assembly D. smooth endoplasmic reticulum—lipid synthesisB. peroxisomes—oxidations of fatty acids or other compounds E. lysosomes—protein synthesisC. cell wall—protection and structural support.3. Cells that line the intestines are known to possess a large number of membrane proteins that transport small molecules and ions across the plasma membrane. Which of the following cell structures would you expect to be required to support this function of these particular cells?A. endoplasmic reticulum D. cell wallB. peroxisomes E. chloroplastsC. lysosomes4. Scientists have found that polypeptides that are normally synthesized in the endoplasmic reticulum are about 20 amino acids longer when they are synthesized by ribosomes not attached to the endoplasmic reticulum. What is/are possible explanations for the greater length of these polypeptides?A. The ribosomes that function as free ribosomes function differently than the ribosomes that are attached to the endoplasmic reticulum.B. The 20 amino acids serve as a signal sequence that directs the forming polypeptide to the endoplasmic reticulum, where these additional amino acids are cleaved off during processing.C. The 20-amino-acid sequence helps the endoplasmic reticulum package these proteins for shipping to the Golgi.D. The protein has a different function in the cytosol than in the endoplasmic reticulum.E. None of the above are reasonable explanations.5. Asbestos is a material that was once used extensively in construction. One risk from working in a building that contains asbestos is the development of asbestosis caused by the inhalation of asbestos fibers. Cells will phagocytize asbestos, but are not able to degrade it. As a result, asbestos fibers accumulate in _____.A. mitochondria D. lysosomesB. ribosomes E. the cell’s nucleusC. peroxisomes6. Which of the following BEST describes the Signal Hypothesis?A. The signal hypothesis explains how proteins intended for secretion from cells follow an orderly process.B. The signal hypothesis explains how proteins destined for secretion enter the endomembrane system.C. The signal hypothesis explains how large molecules enter the nucleus of the cell.D. The signal hypothesis explains how all cellular proteins enter the endomembrane system of the cell.E. The signal hypothesis explains how proteins destined for secretion enter the nucleus of the cell.7. Which of the following is a complex “9 + 2” arrangement of microtubules?A. basal body D. kinesinB. axoneme E. centrosomeC. dynein8. Which of the following is NOT needed in order for cilia and flagella to bend? A. ATP D. basal bodyB. axoneme E. microtubule doubletC. dynein9. A protein that has been engineered to contain a nuclear localization signal (NLS), an ER signal sequence, AND a mannose-6-phosphate tag will ultimately be found WHERE as its final location in the cell?A. a vesicle from the Golgi D. a lysosomeB. the nucleus E. the endoplasmic reticulumC. the cytosolChpt 8: Sects 8.1 & 8.2 Intro to Metabolism10. Which of the following is/are example(s) of the second law of thermodynamics?A. Formation of salt crystals by evaporation.B. An endergonic reaction.C. Formation of an ice cube in the freezer.D. A sugar cube dissolving in a hot cup of coffee.E. All of the above (select answer E if all of the above are examples).11. Consider the mathematical expression ΔG =ΔH - TΔS. As the temperature of a molecule increases, which of the following is/are accurate?A. Thermal energy increases the amount of disorder in the system.B. The change in free energy must increase.C. The enthalpy of the molecule plays a larger role (as compared to when molecule is at a lower temperature) in determining free energy change.D. The entropy of the molecule plays a larger role (as compared to when molecule is at a lower temperature) in determining free energy change.E. Both A and D (select E if both A and D are accurate).12. If an endothermic reaction is spontaneous at 298 degrees K, which of the following must be true for the reaction? (HINT: Use formula from question 11 and review definitions from lecture notes!)I. Δ G is greater than zero.II. Δ H is greater than zero.III. Δ S is greater than zero.A. I, II and III must all be true. D. Only I is true.B. I and II must both be true. E. Only II is true.C. II and III must both be true.13. Examine the below reactions and change in Gibbs Free energy at 298 degrees K associated with them. Then, select the best conclusion that may be drawn from this information. Table 2. Gibbs Free Energy changes for two different synthesis reactions.Δ G (kJ/mol)I. 2 CO2 + 4 H2 → CH3COOH + 2 H2O -392.0acetic acidII. CO2 + 2 H2 → HCHO + H2O 63.0FormaldehydeA. Reaction I is spontaneous whereas reaction II is not. Compared to the reactants from which it is formed, formaldehyde has more potential energy than does acetic acid.B. Reaction I is spontaneous whereas reaction II is not. Compared to the reactants from which it is formed, acetic acid has more potential energy than does formaldehyde.C. Reaction I is spontaneous whereas reaction II is not. Entropy decreases when acetic acid is produced and increases when formaldehyde is produced.D. Reaction II is spontaneous whereas reaction I is not. More heat is produced when formaldehyde is produced compared to the production of acetic acid. E. Both reactions are spontaneous. Entropy increases in both instances.14. If a reaction is endergonic, then which of these statements is TRUE?A. Energy must be added for the reaction to proceed.B. Energy will be given off as the reaction proceeds.C. The products have lower entropy (are more ordered) than the reactants.D. The reaction occurs extremely quickly.E. B & D (select E if both B and D are TRUE).15. Which of the following statements is/are accurate statement(s) about the overall ΔG of the reaction A + B?A. Overall ΔG of the reaction A + B is equal to [ΔG X] + [ΔG Y]B. Overall ΔG of the reaction A + B is positive.C. Overall ΔG of the reaction A + B indicates an exergonic reaction.D. Overall ΔG of the reaction A + B doesn't change, whether it is coupled or uncoupled. E. B