A 1. difference between vertically and horizontally acquired mutations is that A. only vertically-acquired mutations are passed on to progeny cells B. chemical mutagens only induce vertically acquired mutations C. knockout phenotypes only result from vertically-acquired mutations D. horizontally-acquired mutations are more severe 2. Which of the following would generally be the MOST detrimental to a bacterium? A. A missense mutation upstream in a coding region B. A missense mutation downstream in a coding region C. A nonsense mutation upstream in a coding region D. A nonsense mutation downstream in a coding region 3. A base substitution that causes a silent mutation would most likely occur A. in the first base of a codon B. in the third base of a codon C. in the upstream portion of a coding region D. in the downstream portion of a coding region 4. Which of the following is NOT true of quorum sensing? A. It only occurs between different species of bacteria B. It allows bacteria to sense their population density C. It utilizes a diffusible co-inducer molecule D. It leads to changes in gene expression 5. Alkylating agents do NOT
A. promote base substitution mutations B. cause cancer C. modify the chemical structure of DNA bases D. promote indel mutations 6. DNA intercalating agents A. cause an insertion if incorporated into the new strand during DNA replication B. are generally hydrophilic molecules C. most often generate base substitution mutations D. promote frameshift mutation 7. Which of the following is a FALSE statement about DNA methylation? A. it directs mismatch repair B. it's sensed by enzymes C. it can be found on both DNA strands immediately following replication D. it's important for the proper repair of base substitution mutations 8. Thymine dimers A. occur between thymine bases located on opposing DNA strands B. are repaired by the mismatch repair system C. can invoke the SOS response D. cannot be repaired in the dark 9. Which of the following is a FALSE statement about endonucleases? A. they are required for light repair of thymine dimers B. they include restriction enzymes
C. they are required for mismatch repair D. they cut in the middle of DNA strands 10. 5'-bromouracil is an analog of which of the following nucleotides? A. Adenine B. Guanine C. Thymine D. Cytosine 11. The second restriction enzyme isolated from the hypothetical bacterium Universitum' washingtonia would be properly named A. Uwa RII B. Unw RII C. Uis RII D. Uni WII 12. Which of the following is a FALSE statement about DNA transformation? A. It can involve the uptake of eukaryotic DNA B. It can involve the uptake of DNA from the same or a different species of bacteria C. It involves the uptake of single-stranded DNA D. It occurs only under natural settings 13. During cloning, "cutting" and "resealing" of a DNA molecule would require A. polymerase and ligase B. exonuclease and helicase
C. restriction endonuclease and ligase D. methylase and exonuclease 14. Which of the following is NOT true of Bdellovibrio? A. They replicate in the cytoplasm of their host cell B. They modify the cell wall of their host cell C. They swim using a flagellum D. They prey on bacteria 15. Which of the following sequences would be most likely to be found at the junction of human and bacterial DNA sequences in a recombinant DNA molecule? A. 5'-GCTATAGC-3' B. 5'-GCTAAGAT-3' C. 5'-TGATCATA-3' D. 5'-GCATAGCA-3' 16. Mature virions ALWAYS contain 1. a protein capsid 2. peptidoglycan 3. a cell wall 4. a lipid envelope 5. nucleic acid A. 1, 2 B. 1, 3 C. 1, 5 D. 1, 4, 5 E. 3, 4,
17. An antibiotic resistance gene located in a conjugative plasmid of one bacterium (the donor) can be transferred to another, incompetent bacterium (the recipient) via A. conjugation after death of the donor cell B. specialized transduction by a phage whose integration site is located in the chromosome of the donor and the recipient cell C. generalized transduction by a lytic phage D. transformation after death of the donor E. membrane fusion 18. The term "plaque forming units" refers to A. a technique for studying the role of bacteria in the development of dental cavities B. a unit for expressing the concentration of bacteria in a given sample C. a unit for expressing the concentration of lytic viruses in a given sample D. a unit for expressing the concentration of integrated (lysogenized) phages in a given sample 19. Which of the following statements is TRUE? A. Infecting bacteriophages always replicate in the cytoplasm of the host cell B. The capsids of bacteriophages always enter the host cell C. All bacteriophages are capable of producing a latent infection D. In contrast to animal viruses, the capsid of bacteriophages are not made of protein E. Animal viruses contact their host cells via fibers at the end of the protein tails 20. Retroviruses are __________ viruses that must synthesize ___________ intermediates to ____________ in the host _____________. A. DNA / RNA / replicate / nucleus B. DNA / DNA / integrate / plasmids
C. RNA / RNA / integrate / chromosome D. RNA / DNA / integrate / chromosome 21. A persistent virus may transform its host cell into a tumor cell by 1. altering the cell membrane as it exits via budding 2. inducing chronic inflammation and the production of oxygen radicals 3. integrating into the chromosome 4. inducing cell death A. 1 & 2 B. 2 & 3 C. 3 & 4 D. 1 & 3 E. 2, 3 & 4 22. The bacterial defense mechanism against phage infection LEAST likely to interfere with the normal physiology of the infected/targeted cell is A. abortive infection system B. CRISPRs with specificity to the infecting phage C. modification of the receptors recognized by the infecting phage D. spore formation E. metabolic stasis 23. A positive, single stranded RNA virus must A. be targeted to the nucleus of the host cell for replication its of genome using host cell proteins B. code for an RNA-dependent RNA polymerase C. translate its genes into protein from an RNA molecule complementary to its genome
D. synthesize capsid proteins inside the host cell nucleus 24. Which of the following statements is FALSE when applied to ALL viruses? 1. They carry genes necessary for the synthesis of ribosomes 2. They harvest energy by using their own enzymes 3. They must uncoat before being able to express their own proteins 4. They are obligate intracellular parasites 5. They must import into the host cell any protein needed for expression of their genes if not available within the host cell A. 1 & 2 B. 2 & 3 C. 3 & 4 D. 1 & 4 E. 1 & 5 25. A polyprotein is A. a large protein capable of carrying out multiple functions B. a series of joined proteins that must be separated to become fully functional C. produced by translation of a polycistronic transcript D. A & C E. B & C 26. "Minimum inhibitory concentration" refers to A. the minimum concentration of a growth substrate below which growth cannot occur B. the minimum concentration of an antimicrobial that will cause toxicity in a human C. the minimum concentration of bacterial cells needed to induce cell death due to crowding D. the minimum concentration of an antibacterial that will inhibit viral growth
E. the minimum concentration of an antibacterial that will inhibit bacterial growth 27. A bacteriostatic antibiotic A. buys the host some time so that its immune system may clear the infection B. kills bacteria by weakening their cell walls and allowing them to lyse C. inhibits bacterial growth by generating an electrostatic field D. interferes with viral processes thus preventing viral proliferation E. generates oxygen radicals that destroy bacterial DNA 28. An antimicrobial that interferes with the synthesis of lipopolysaccharide A. likely has a low therapeutic index due to high toxicity for eukaryotic cells B. is likely to be most effective against Gram-negative bacteria C. will likely prevent the replication of enveloped viruses D. is likely capable of lysing Gram-positive bacteria E. is likely ineffective against Gram-negative bacteria because of intrinsic resistance 29. Bacterial resistance to a given antibiotic A. can arise by acquisition of new genes via conjugation B. can arise through small mutations C. can occur by changing the activity of transporters without altering the target structure D. A & B E. A, B & C 30. Which of the following is the LEAST likely mode of action for an effective and medically useful antiviral agent?
A. Interference with uncoating of viral genomes B. Interference with RNA-dependent DNA polymerases C. Interference with DNA-dependent DNA polymerases D. Interference with the processing of polyproteins E. Degradation of double-stranded RNAs 31. As part of our innate immune defense, the normal microbiota help confer protection through all of the following mechanisms EXCEPT A. competing with potential pathogens for space B. competing with potential pathogens for nutrients C. producing lysozyme D. producing antimicrobial compounds E. all of the above are protective functions of the normal microbiota 32. The IMMEDIATE response of a cell that has detected interferon is to A. synthesize inactive antiviral proteins B. synthesize co-stimulatory molecules C. undergo clonal expansion D. form a membrane attack complex E. process the interferon and present the resulting antigens to a T cell 33. The most common response following the opsonization of an antigen by complement is A. a primary immune response B. a secondary immune response C. macrophage activation
D. phagocytosis E. inflammation 34. The "first line" of innate immune defense includes A. epithelium B. complement C. granulocytes D. macrophages E. inflammation 35. The FIRST class of immunoglobulin produced in response to a foreign antigen is A. IgA B. IgM C. IgG D. IgD E. IgE 36. A primary function of TH cells is to A. collect and present antigen B. induce apoptosis in virallyVinfected cells C. activate macrophages D. produce immunoglobulin E. activate a secondary immune response 37. A primary function of plasma cells is to
A. collect and present antigen B. induce apoptosis in virallyVinfected cells C. activate macrophages D. produce immunoglobulin E. activate a secondary immune response 38. A "membrane attack complex" is an immune defense mechanism associated with A. cytotoxic T lymphocytes B. activated macrophages C. complement D. phagolysosomal fusion E. interferon 39. The standard treatment for haemolytic disease of newborns is to inject the RhVmother with anti-Rh IgG immediately after the birth of her Rh+ child. The purpose of this treatment is to block the activation of A. a primary immune response B. a secondary immune response C. memory cells D. plasma cells E. macrophages 40. Cytokines released by cytotoxic T cells may stimulate other cells to A. undergo clonal expansion B. undergo apoptosis
C. increase the synthesis of lysosomes D. produce toxic oxide radicals E. all of the above 41. Which of the following cell types does NOT present antigen to TH cells? A. B cells B. Tc cells C. dendritic cells D. macrophages E. all of the above present antigen to TH cells 42. HIV infection can lead to immunodeficiency because the virus specifically attacks A. macrophages B. granulocytes C. B lymphocytes D. TC lymphocytes E. TH lymphocytes 43. A "heavy chain" polypeptide forms part of a(n) A. MHC protein B. CD protein C. tollVlike receptor D. B cell receptor E. T cell receptor
44. MHC I is a protein normally found on A. B lymphocytes B. TC lymphocytes C. TH lymphocytes D. dendritic cells E. all of the above 45. CD 4 is a protein normally found on A. B lymphocytes B. TC lymphocytes C. TH lymphocytes D. dendritic cells E. all of the above