front 1 1) How do all viruses differ from bacteria? A) Viruses are filterable. B) Viruses are obligate intracellular parasites. C) Viruses do not have any nucleic acid. D) Viruses are not composed of cells. E) Viruses do not reproduce. | back 1 Answer: D |
front 2 2) Which of the following statements provides the most significant support for the idea that viruses are nonliving chemicals? A) They are not composed of cells. B) They are filterable. C) They cannot reproduce themselves outside a host. D) They cause diseases similar to those caused by chemicals. E) They are chemically simple. | back 2 Answer: C |
front 3 3) Which of the following statements about viral spikes is FALSE? A) They are composed of carbohydrate-protein complexes. B) They are used for attachment. C) They may cause hemagglutination. D) They bind to receptors on the host cell surface. E) They are found only on nonenveloped viruses. | back 3 Answer: E |
front 4 4) Which of the following is NOT used as a criterion to classify viruses? A) biochemical tests B) morphology C) nucleic acid D) size E) number of capsomeres | back 4 Answer: A |
front 5 5) Which of the following is NOT utilized to culture viruses? A) laboratory animals B) culture media C) embryonated eggs D) animal cell cultures E) bacterial cultures | back 5 Answer: B |
front 6 6) Bacteriophages and animal viruses do NOT differ significantly in which one of the following steps? A) attachment B) penetration C) uncoating D) biosynthesis E) release | back 6 Answer: D |
front 7 7) The definition of lysogeny is A) phage DNA is incorporated into host cell DNA. B) lysis of the host cell due to a phage. C) the period during replication when virions are not present. D) when the burst time takes an unusually long time. E) attachment of a phage to a cell. | back 7 Answer: A |
front 8 8) A viroid is a(n) A) complete, infectious virus particle. B) infectious piece of RNA without a capsid. C) capsid without nucleic acid. D) provirus. E) infectious protein. | back 8 Answer: B |
front 9 9) In Figure 13.1, which structure is a complex virus?
| back 9 Answer: B |
front 10 10) The structures illustrated in Figure 13.1 are composed of A) DNA. B) RNA. C) DNA or RNA. D) Capsomeres. E) viroids. | back 10 Answer: D |
front 11 11) A clear area against a confluent "lawn" of bacteria is called a A) phage. B) pock. C) cell lysis. D) plaque. E) rash. | back 11 Answer: D |
front 12 12) Continuous cell lines differ from primary cell lines in that A) viruses can be grown in continuous cell lines. B) continuous cell lines always have to be re-isolated from animal tissues. C) continuous cell lines are derived from primary cell lines. D) continuous cell lines can be maintained through an indefinite number of generations. E) continuous cell lines are from human embryos. | back 12 Answer: D |
front 13 13) Which of the following is necessary for replication of a prion? A) DNA B) DNA polymerase C) lysozyme D) PrPSc E) RNA | back 13 Answer: D |
front 14 14) A persistent infection is one in which A) the virus remains in equilibrium with the host without causing a disease. B) viral replication is unusually slow. C) the disease process occurs gradually over a long period. D) host cells are gradually lysed. E) host cells are transformed. | back 14 Answer: C |
front 15 15) Which of the following statements is FALSE? A) A prophage is phage DNA inserted into a bacterial chromosome. B) A prophage can "pop" out of the chromosome. C) Prophage genes are repressed by a repressor protein coded for by the prophage. D) A prophage may result in new properties of the host cell. E) The prophage makes the host cell immune to infection by other phages. | back 15 Answer: E |
front 16 16) Lysogeny can result in all of the following EXCEPT A) immunity to reinfection by the same phage. B) acquisition of new characteristics by the host cell. C) immunity to reinfection by any phage. D) specialized transduction. E) phage conversion. | back 16 Answer: C |
front 17 17) Which of the following would be the first step in biosynthesis of a virus with a - (minus) strand of RNA? A) synthesis of DNA from an RNA template B) synthesis of double-stranded RNA from an RNA template C) synthesis of double-stranded RNA from a DNA template D) transcription of mRNA from DNA E) synthesis of DNA from a DNA template | back 17 Answer: B |
front 18 18) An infectious protein is a A) bacteriophage. B) prion. C) retrovirus. D) viroid. E) papovavirus. | back 18 Answer: B |
front 19 19) An envelope is acquired during which of the following steps? A) penetration B) adsorption C) uncoating D) biosynthesis E) release | back 19 Answer: E |
front 20 20) Which of the following statements is NOT true of lysogeny? A) It can give infected pathogens the genetic information for toxin production. B) Prophage is inserted into the host genome. C) Lytic cycle may follow lysogeny. D) It is a "silent" infection; the virus does not replicate. E) It causes lysis of host cells. | back 20 Answer: E |
front 21 21) An example of a latent viral infection is A) subacute sclerosing panencephalitis. B) cold sores. C) influenza. D) smallpox. E) mumps. | back 21 Answer: B |
front 22 22) A virus's ability to infect an animal cell depends primarily upon the
| back 22 Answer: B |
front 23 23) Assume you have isolated an unknown virus. This virus has a single, positive sense strand of RNA, and possesses an envelope. To which group does it most likely belong? A) herpesvirus B) picornavirus C) retrovirus D) togavirus E) papovavirus | back 23 Answer: D |
front 24 24) The mechanism whereby an enveloped virus leaves a host cell is called A) transduction. B) budding. C) abduction. D) lysogeny. E) penetration. | back 24 Answer: B |
front 25 25) The most conclusive evidence that viruses cause cancers is provided by A) finding oncogenes in viruses. B) the presence of antibodies against viruses in cancer patients. C) cancer following injection of cell-free filtrates. D) treating cancer with antibodies. E) some liver cancer patients having had hepatitis. | back 25 Answer: C |
front 26 26) Bacteriophages derive all of the following from the host cell EXCEPT A) lysozyme. B) tRNA. C) amino acids. D) nucleotides. E) ATP. | back 26 Answer: A |
front 27 27) Bacteriophage replication differs from animal virus replication because only bacteriophage replication involves A) adsorption to specific receptors. B) assembly of viral components. C) replication of viral nucleic acid. D) injection of naked nucleic acid into the host cell. E) lysis of the host cell. | back 27 Answer: D |
front 28 28) Generally, in an infection caused by a DNA-containing virus, the host animal cell supplies all of the following EXCEPT A) RNA polymerase. B) nucleotides. C) DNA polymerase. D) tRNA. E) None of the answers are correct; all of these are supplied by the host animal cell. | back 28 Answer: C |
front 29 29) Which of the following places these items in the correct order for DNA-virus replication?
| back 29 Answer: B |
front 30 30) A viral species is a group of viruses that A) has the same morphology and nucleic acid. B) has the same genetic information and ecological niche. C) infects the same cells and cause the same disease. D) cannot be defined. | back 30 Answer: B |
front 31 31) Viruses that utilize reverse transcriptase belong to the virus
families | back 31 Answer: C |
front 32 32) DNA made from an RNA template will be incorporated into the virus capsid of A) Retroviridae. B) Herpesviridae. C) Hepadnaviridae. D) bacteriophage families. E) influenzavirus. | back 32 Answer: C |
front 33 33) Which of the following statements about viruses is FALSE? A) Viruses contain DNA or RNA but never both. B) Viruses contain a protein coat. C) Viruses use the anabolic machinery of the cell. D) Viruses use their own catabolic enzymes. E) Viruses have genes. | back 33 Answer: D |
front 34 34) A lytic virus has infected a patient. Which of the following would best describe what is happening inside the patient? A) The virus is causing the death of the infected cells in the patient. B) The virus is not killing any cells in the host. C) The virus is incorporating its nucleic acid with that of the patient's cells. D) The virus is slowly killing the patient's cells. E) The virus is infecting cells and then releasing only small amounts of virus. | back 34 Answer: A |
front 35 35) Some viruses, such as human herpesvirus 1, infect a cell without causing symptoms. These are called A) latent viruses. B) lytic viruses. C) phages. D) slow viruses. E) unconventional viruses. | back 35 Answer: A |
front 36 36) Assume a patient had chickenpox (human herpesvirus 3) as a child. Which line on the graph in Figure 13.2 would show the number of viruses present in this person as a 60-year-old with shingles (human herpesvirus 3)? A) a B) b C) c D) d E) e | back 36 Answer: E |
front 37 37) Assume a patient has influenza. During which time on the graph in Figure 13.2 would the patient show the symptoms of the illness? A) a B) b C) c D) d E) e | back 37 Answer: C |
front 38 38) The following steps occur during multiplication of herpesviruses. Which is the third step? A) attachment B) biosynthesis C) penetration D) release E) uncoating | back 38 Answer: E |
front 39 39) The following steps occur during multiplication of retroviruses. Which is the fourth step? A) synthesis of double-stranded DNA B) synthesis of +RNA C) attachment D) penetration E) uncoating | back 39 Answer: A |
front 40 40) Oncogenic viruses A) cause acute infections. B) are genetically unstable. C) cause tumors to develop. D) are lytic viruses that kill the host cell. E) have no effect on the host cell. | back 40 Answer: C |
front 41 41) Which one of the following steps does NOT occur during multiplication of a picornavirus? A) synthesis of + strands of RNA B) synthesis of - strands of RNA C) synthesis of viral proteins D) synthesis of DNA E) None of the answers is correct. | back 41 Answer: D |
front 42 42) Which of the following is most likely a product of an early gene? A) capsid proteins B) DNA polymerase C) envelope proteins D) spike proteins E) lysozyme | back 42 Answer: B |
front 43 43) Most RNA viruses carry which of the following enzymes? A) DNA-dependent DNA polymerase B) lysozyme C) RNA-dependent RNA polymerase D) reverse transcriptase E) ATP synthase | back 43 Answer: C |
front 44 44) The following steps occur during biosynthesis of a + strand RNA virus. What is the third step? A) attachment B) penetration and uncoating C) synthesis of - strand RNA D) synthesis of + strand RNA E) synthesis of viral proteins | back 44 Answer: C |
front 45 45) What contributes to antigenic shift in influenza viruses? A) worldwide distribution of the virus B) a segmented genome C) attachment spikes D) ease of virus transmission E) different virus subtypes | back 45 Answer: B |
front 46 46) ________ were first identified in cancer-causing viruses and can induce ________ in infected cells. A) Herpes viruses; lesions B) Oncogenes; transformation C) T antigens; lysis D) Glycoprotein spikes; syncytia formation E) Segmented genomes; reassortment | back 46 Answer: B |
front 47 1) The basic mechanism of viral multiplication is similar for all viruses. | back 47 Answer: TRUE |
front 48 2) A viroid is a completely developed infectious agent composed of nucleic acid and surrounded by a capsid. | back 48 Answer: FALSE |
front 49 3) Binomial nomenclature is used to name viruses. | back 49 Answer: FALSE |
front 50 4) Glycoprotein spikes are found on the capsids of all viruses. | back 50 Answer: FALSE |
front 51 5) Positive sense RNA strands of viruses are treated like mRNA inside the host cell. | back 51 Answer: TRUE |
front 52 6) Dogs do not get measles because their cells lack the correct receptor sites for that virus. | back 52 Answer: TRUE |
front 53 7) Helical and icosahedral are terms used to describe the shapes of a virus envelope. | back 53 Answer: FALSE |
front 54 8) Viruses are the only known infectious agents that are obligatory intracellular parasites. | back 54 Answer: FALSE |
front 55 9) A segmented genome can result in antigenic shift. | back 55 Answer: TRUE |
front 56 10) Most drugs that interfere with viral multiplication also interfere with host cell function. | back 56 Answer: TRUE |