CH 13
Which of the following statements is FALSE?
The prophage makes the host cell immune to infection by other phages.
A prophage is phage DNA inserted into a bacterial chromosome.
Prophage genes are repressed by a repressor protein coded for by the prophage.
A prophage may result in new properties of the host cell.
A prophage can "pop" out of the chromosome.
The prophage makes the host cell immune to infection by other phages.
An infectious protein is a
papovavirus.
retrovirus.
prion.
viroid.
bacteriophage.
prion
A viroid is a completely developed infectious agent composed of nucleic acid and surrounded by a capsid.
True/False
False
Which of the following places these items in the correct order for
DNA-virus replication?
1. Maturation
2. DNA synthesis
3. Transcription
4. Translation
2,3,4,1
Which of the following statements provides the most significant support for the idea that viruses are nonliving chemicals?
They are filterable.
They cause diseases similar to those caused by chemicals.
They are chemically simple.
They are not composed of cells.
They cannot reproduce themselves outside a host.
They cannot reproduce themselves outside a host.
Which one of the following steps does NOT occur during multiplication of a picornavirus?
synthesis of DNA
synthesis of + strands of RNA
synthesis of - strands of RNA
synthesis of viral proteins
None of the answers is correct.
synthesis of DNA
Continuous cell lines differ from primary cell lines in that:
viruses can be grown in continuous cell lines.
continuous cell lines can be maintained through an indefinite number of generations.
continuous cell lines are derived from primary cell lines.
continuous cell lines always have to be re-isolated from animal tissues.
continuous cell lines are from human embryos.
continuous cell lines can be maintained through an indefinite number of generations.
Which of the following would be the first step in biosynthesis of a virus with a - (minus) strand of RNA
synthesis of DNA from a DNA template
synthesis of DNA from an RNA template
transcription of mRNA from DNA
synthesis of double-stranded RNA from an RNA template
synthesis of double-stranded RNA from a DNA template
synthesis of double-stranded RNA from an RNA template
An envelope is acquired during which of the following steps?
uncoating
biosynthesis
penetration
release
adsorption
release
Lysogeny can result in all of the following EXCEPT
immunity to reinfection by any phage.
specialized transduction.
immunity to reinfection by the same phage.
phage conversion.
acquisition of new characteristics by the host cell.
immunity to reinfection by any phage.
Bacteriophage replication differs from animal virus replication because only bacteriophage replication involves?
adsorption to specific receptors.
lysis of the host cell.replication of viral nucleic acid.
injection of naked nucleic acid into the host cell.assembly of viral components.
injection of naked nucleic acid into the host cell
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
C) c
Viruses are the only known infectious agents that are obligatory intracellular parasites.
True/False
False
A virus's ability to infect an animal cell depends primarily upon the
type of viral nucleic acid.
presence of receptor sites on the cell membrane.
presence of pili on the host cell wall.
enzymatic activity of a host cell.
host cell's ability to phagocytize viral particles.
presence of receptor sites on the cell membrane.
________ 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
B) Oncogenes; transformation
Helical and icosahedral are terms used to describe the shapes of a virus envelope.
True/False
False
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
B) culture media
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.
A) The virus is causing the death of the infected cells in the patient.
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.
B) infectious piece of RNA without a capsid.
Which of the following is necessary for replication of a prion?
A) DNA
B) DNA polymerase
C) lysozyme
D) PrPSc
E) RNA
D) PrPSc
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.
A) latent viruses.
An example of a latent viral infection is
A) subacute sclerosing panencephalitis.
B) cold sores.
C) influenza.
D) smallpox.
E) mumps.
B) cold sores.
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.
A) phage DNA is incorporated into host cell DNA.
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.
D) Viruses are not composed of cells.
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
B) DNA polymerase
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
C) synthesis of - strand RNA
4) Glycoprotein spikes are found on the capsids of all viruses.
True/False
False
Binomial nomenclature is used to name viruses.
True/False
False
31) Viruses that utilize reverse transcriptase belong to the virus
families
A) Retroviridae and Picornaviridae.
B)
Herpesviridae and Retroviridae.
C) Hepadnaviridae and
Retroviridae.
D) Herpesviridae and Poxviridae.
E)
Rhabdoviridae and Herpesviridae.
C) Hepadnaviridae and Retroviridae.
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
D) togavirus
Most drugs that interfere with viral multiplication also interfere with host cell function.
True/False
True
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.
D) Viruses use their own catabolic enzymes.
Dogs do not get measles because their cells lack the correct receptor sites for that virus.
True/False
True
38) The following steps occur during multiplication of herpesviruses. Which is the third step?
A) attachment
B) biosynthesis
C) penetration
D) release
E) uncoating
E) uncoating
The basic mechanism of viral multiplication is similar for all viruses.
True