Microbiology Practice Exam 3, Exams of Microbiology

Download Microbiology Practice Exam 3 and more Exams Microbiology in PDF only on Docsity! Approved by Dr. Ambivero Summer 2020 Made by your Peer Tutor Page 1 of 6 Microbiology Practice Exam 3 1. Which of the following is not true regarding ATP synthase? a. It requires a proton motive force to produce ATP b. It spans across the inner mitochondrial membrane c. The proton flow is outward during ATP synthesis d. It is an enzyme that catalyzes the reaction of AMP to ATP 2. During glycolysis, ATP is produced when 1,3 biphosphoglycerate transfers a phosphate to ADP forming ATP. This is an example of: a. Substrate-level phosphorylation b. Glycolytic phosphorylation c. Oxidative phosphorylation d. Photophosphorylation 3. Counting only ATP made from SLP, how many ATP are made per glucose during respiration? a. 1 b. 4 c. 32 d. 0 4. Lipid catabolism: a. Is hydrolyzed by lipidases b. Produces glycerol degraded via β-oxidation pathway c. Fatty acids are shortened by 2 carbons during each cycle d. Fatty acids are oxidized after being linked to coenzyme A via the dihydroxyacetone phosphate 5. Plants growing in soil with P. denitrificans would undergo which of the following: a. Increased growth due to oxygen elimination from the soil b. Increased growth due to C and N addition to the soil c. Decreased growth due to assimilatory nitrate reduction d. Decreased growth due to dissimilatory nitrate reduction e. Both A & C 6. Energy releasing reactions in the cells are called _______ and are ∆G __________. a. Endergonic; negative b. Exothermic; negative c. Exergonic; positive d. Exergonic; negative e. Endergonic; positive 7. Fermentation: a. Produces 2 net ATP b. May produce lactic acid c. Both SLP and OP are used to produce ATP Approved by Dr. Ambivero Summer 2020 Made by your Peer Tutor Page 2 of 6 d. Produces 30 net ATP e. Both A & B 8. The _______ is the electron acceptor in a redox reaction. a. Reductant b. Reducing Agent c. Oxidant d. Both B & C e. All of the above 9. Which of the following is true of the Calvin-Benson cycle? Select all that apply a. It consist of 3 phases b. It uses CO2 to produce metabolic intermediates c. The reduction phase ends with the production of glyceraldehyde 3-P d. Some of the 12 C skeletons can be produced in the regeneration phase e. 3-phosphoglycerate is oxidized to glyceraldehyde 3-P 10. Which reaction would be catalyzed by a ribozyme? a. The phosphorylation of glucose b. Reduction of O2 to form H2O c. Deamination of tRNA d. Peptide bond formation 11. BONUS: Describe the three pathways that catabolize the reaction of glucose to glyceraldehyde 3-P, and how they all interact with each other. What are the end products of each, and what is unique about each of them? 12. Select the groups that can be used to covalently modify an enzyme’s activity. a. Methyl b. Carboxyl c. Carbonyl d. Phosphoryl e. Adenyl 13. You prescribe a patient the drug Methotrexate that acts as an enzyme inhibitor. This drug inhibits the enzyme dihydrofolate reductase which prevents the regeneration of dihydrofolate from tetrahydrofolate, interfering with DNA synthesis and inhibiting cell division in cancer cells. This patient is also begins taking another drug that contains the folate tetrahydrofolate, and upon beginning this drug cancer cell division recurs. Which of the following types of enzyme inhibitors is Methotrexate? a. Non-competitive inhibitor b. Competitive inhibitor 14. In the TCA cycle, two carbons in the form of _________ are added to oxaloacetate. a. Malate b. Ethanol c. Carbon Dioxide d. Acetyl-coA Approved by Dr. Ambivero Summer 2020 Made by your Peer Tutor Page 5 of 6 b. 2 e/2 p c. 2 e/1 p d. 1 e/1 p 29. In the electron transport chain: a. Coupling sites are where protons are pumped out of the mitochondria b. The FeS protein accepts electrons and protons, but only transfers electrons c. The transfer of electrons through the chain produces a high concentration of protons outside the cell d. The redox potential of pairs at the beginning of the chain are more negative than those at the end of the chain e. All of the above 30. The pentose phosphate pathway produces: a. E4P b. Glyceraldehyde-3-phosphate c. Acetyl-CoA d. All of the above e. Both A & B 31. BONUS: What is the role of the PMF in the ETC? What about ATP synthase? Describe the roles of the transporters (such as cytochrome and coenzyme Q) and the net yield of ATP. 32. Which of the following statements is/are true? Select all that apply. a. Isoenzymes are the same enzymes that catalyze different reactions b. The ETC in bacterial cells is located in the mitochondrial matrix c. In a branched pathway, one end produce in excess can inhibit the first step in the pathway d. GTP is used for signaling e. Enzymes speed up the rate at which a reaction proceeds towards its final end product, shifting equilibrium towards the products 33. Which of the following can be an electron acceptor in anaerobic respiration? a. SO4 2− b. NO2 − c. O2 d. N2 34. Which of the following is considered an irreversible post-translational modification? a. Allosteric regulation at a regulatory site b. Covalent modification of an enzyme c. Cleavage of an amino acid from an enzyme d. All of the above are irreversible 35. Erythrose-4-phosphate and phosphoenolpyruvate are used to make the aromatic amino acids. Which of the following is correct? a. They can be used to form chorismite b. Aromatic amino acid formation occurs in the fueling phase Approved by Dr. Ambivero Summer 2020 Made by your Peer Tutor Page 6 of 6 c. They are both 12 carbon skeletons used to make all of the building blocks in prokaryotes d. All of the above e. Both A & C 36. Enzymes: a. Increase the velocity of a reaction by lowering activation of energy b. When binding to a substrate, they bind like a lock and key c. Have an active binding site for the substrate and a different for allosteric inhibitor d. Both A & C e. All of the above 37. The heme group in cytochrome c: a. Is a coenzyme b. Is a prosthetic group c. Can transport electrons and protons d. All of the above 38. The carboxylation phase in the Calvin-Benson cycle is catalyzed by: a. 3-phosphoglycerate b. Glyceraldehyde 2-P c. Ribulose biphosphate carboxylase/oxygenase (RuBisCO) d. Rubulose-1,5-biphosphate 39. The reductive TCA cycle is used by: a. Chemolithoautotrophs b. Photolithoautotrophs c. Chemoorganoheterotrophs d. Chemoorganotrophs 40. Which of the following organisms uses organic carbon as a carbon source, light as an energy source, and organic compounds as an electron source? a. Photolithoautotrophs b. Chemilithoautotrophs c. Chemoorganoheterotroph d. Photoorganoheterotroph 41. BONUS: What are the 6 carbon skeletons that are made in EMP?