Micro Ch. 5 Quiz

Which of the following is not a characteristic of a transformed cell? a. Viral nucleic acid integrated into host DNA b. Decreased growth rate c. Alterations in chromosomes d. Changes in cell surface molecules e. Capacity to divide indefinitely

b. Decreased growth rate

What structures are used by bacteriophages to attach to host cell receptors? a. Sheath b. Tail fibers c. Nucleic acid d. Capsid head e. None of the choices are correct

b. Tail fibers

Satellite viruses are ________. a. also called viroids b. dependent on other viruses for replication c. the cause of spongiform encephalopathies d. significant pathogens of plants e. All of the choices are correct

b. dependent on other viruses for replication

The activation of a prophage is called _____. a. adsorption b. induction c. lysogeny d. activation e. transformation

b. induction

When a bacterium acquires a trait from its temperate phage, it is called _____. a. transcription b. lysogenic conversion c. transformation d. viral persistence e. translation

b. lysogenic conversion

Viruses have all the following except ________. a. definite shape b. metabolism c. genes d. the ability to infect host cells e. ultramicroscopic size

b. metabolism

Viral spikes ________. a. are present on all viruses b. protrude from the envelope c. block attachment between virus and host d. are derived from host proteins e. All of the choices are correct

b. protrude from the envelope

Viruses that infect bacteria are specifically called _____. a. viroids b. prions c. bacteriophages d. satellite viruses e. All of the choices infect bacteria.

c. bacteriophages

One of the principal capsid shapes is a 20-sided figure with 12 evenly spaced corners referred to as a(n) _______ capsid. a. spiked b. complex c. icosahedral d. helical e. buckeyball

c. icosahedral

Visible, clear, well-defined patches in a monolayer of virus-infected cells in a culture are called _____. a. lysogeny b. pocks c. plaques d. cytopathic effects e. budding

c. plaques

Infectious protein particles are called _____. a. viroids b. oncogenic viruses c. prions d. spikes e. phages

c. prions

Which of the following is incorrect about prophages? a. Present when the virus is in lysogeny b. Formed when viral DNA enters the bacterial chromosome c. Replicated with host DNA and passed on to progeny d. Cause lysis of host cells e. Occur when temperate phages enter host cells

d. Cause lysis of host cells

Reverse transcriptase synthesizes ________. a. the positive RNA strand from a negative RNA strand b. a negative RNA strand from a positive RNA strand c. RNA from DNA d. DNA from RNA e. None of the choices are correct

d. DNA from RNA

Viral tissue specificities are called _____. a. virions b. receptacles c. uncoating d. tropisms e. ranges

d. tropisms

Lysogeny refers to ________. a. altering the host range of a virus b. latent state of herpes infections c. virion exiting host cell d. viral genome inserting into bacterial host chromosome e. None of the choices are correct

d. viral genome inserting into bacterial host chromosome

Uncoating of viral nucleic acid ________. a. does not occur in bacteriophage multiplication b. involves enzymatic destruction of the capsid c. releases viral nucleic acid into the cell d. occurs before replication e. All of the choices are correct

e. All of the choices are correct

Viral nucleic acids include which of the following? a. Double-stranded DNA b. Single-stranded DNA c. Double-stranded RNA d. Single-stranded RNA e. All of the choices are correct

e. All of the choices are correct

Two noncellular agents, smaller than viruses, are the infectious proteins called _______ and the infectious RNA strands called ________. a. prions; capsomeres b. virions; prions c. viroids; phages d. prions; phages e. prions; viroids

e. prions; viroids

Which of the following is not a typical capsid shape? a. Tetrahedral b. Complex c. Helical d. Icosahedron e. All of the choices are capsid shapes.

a. Tetrahedral

Persistent viruses that can reactivate periodically are _____. a. chronic latent viruses b. oncoviruses c. syncytia d. inclusion bodies e. cytopathic

a. chronic latent viruses

Viral genetic studies, vaccine development and clinical identification would not be possible without the ability to ________. a. culture viruses in vivo and in vitro b. transform human cells into cancerous cells c. studying prions in neurological tissue of animals d. activate lysogenic induction in bacteriophages

a. culture viruses in vivo and in vitro

Viruses attach to their hosts via ________. a. host glycoproteins b. host phospholipids c. viral phospholipids d. viral flagella e. All of the choices are correct

a. host glycoproteins

New, nonenveloped virus release occurs by _____. a. lysis b. budding c. exocytosis d. both lysis and budding e. both budding and exocytosis

a. lysis

Cells grown in culture form a(n) _____. a. monolayer b. bilayer c. aggregate d. plaque e. None of the choices are correct.

a. monolayer

Viruses with _______ -sense RNA contain the correct message for translation, while viruses with _______ -sense RNA must first be converted into a correct message. a. positive; negative b. negative; positive c. primary; secondary d. secondary; primary e. none of the choices are correct

a. positive; negative