Viral Genome Structure and Evolution Quiz
54 Questions
3 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is a virion?

  • A virus's genetic material
  • A virus's protein synthesis machinery
  • A complete virus particle outside of the host cell (correct)
  • A virus that can infect multiple species
  • Why do viruses need to get into the host cell to survive?

  • They don't have their own metabolic machinery (correct)
  • They need to replicate their genetic material outside the cell
  • They cannot survive in the extracellular environment
  • They require specific nutrients from the host cell
  • What encases the newly replicated viral genome?

  • Capsid
  • Viral structural proteins (correct)
  • Viral lipid envelope
  • Host cell's membrane
  • What is the genetic material of a virion?

    <p>Either DNA or RNA</p> Signup and view all the answers

    What is the function of a virus's capsid?

    <p>Protective coat for the virus</p> Signup and view all the answers

    Which of the following is a mechanism for viral budding?

    <p>Assembly of nucleocapsids directly at the membrane during budding</p> Signup and view all the answers

    What determines virus classification?

    <p>Molecular architecture, genetic relatedness, and host organism</p> Signup and view all the answers

    What is a characteristic of viruses with dsDNA genomes?

    <p>Most have segmented genomes and icosahedral capsids</p> Signup and view all the answers

    Which enzyme is packaged in the virion of viruses with a reverse transcriptase (RT) step in their replication cycle?

    <p>RNA-dependent RNA polymerase</p> Signup and view all the answers

    What is a characteristic of most "-" RNA genomes?

    <p>They do not have envelopes, except for COVID</p> Signup and view all the answers

    Which cellular process is triggered by a low pH during virus entry?

    <p>Membrane fusion</p> Signup and view all the answers

    How are fusion proteins involved in virus-induced membrane fusion?

    <p>They reveal a fusion peptide that gets inserted into the target cellular membrane</p> Signup and view all the answers

    What is the main strategy for viruses to pass through the nuclear membrane?

    <p>Piggyback on machinery used for protein and nucleic acid trafficking</p> Signup and view all the answers

    How do non-enveloped viruses transfer their genetic material from endosome to cytoplasm?

    <p>Through permeabilization of endosomal membrane or lysis</p> Signup and view all the answers

    What is the function of macropinosomes in virus entry?

    <p>They are large vacuoles involved in the internalization of fluid, solutes, and small particles</p> Signup and view all the answers

    What are the characteristics used to determine viruses?

    <p>Genome type, capsid symmetry, envelope presence, and dimensions</p> Signup and view all the answers

    What did the Hershey and Chase experiment demonstrate?

    <p>DNA as the carrier of inheritance information</p> Signup and view all the answers

    What do RNA viruses pose challenges for?

    <p>mRNA synthesis and genome replication</p> Signup and view all the answers

    What do bacteriophages infect?

    <p>Bacteria</p> Signup and view all the answers

    What is commonly used for assaying viruses due to their visible and stable nature?

    <p>Red blood cells</p> Signup and view all the answers

    What is the process of developing viral envelopes at the cell membrane called?

    <p>Budding</p> Signup and view all the answers

    What prevents dehydration and viral aggregation in viral envelopes?

    <p>Glycosylation of envelope proteins</p> Signup and view all the answers

    What is the function of core proteins in viral assembly?

    <p>Neutralize the negative charges on DNA and condense the viral DNA</p> Signup and view all the answers

    Where are envelope proteins synthesized and inserted?

    <p>Synthesized on ribosomes in the ER and inserted into the plasma membrane</p> Signup and view all the answers

    What directs the specificity for incorporation of viral genomes into virions?

    <p>Packaging signals</p> Signup and view all the answers

    Which of the following is true about dsRNA viruses?

    <p>They have fragmented genomes and capsids with icosahedral symmetry</p> Signup and view all the answers

    What is a characteristic of viroids?

    <p>They do not encode for proteins and replicate independent of other viruses</p> Signup and view all the answers

    What does reverse transcriptase do in viral replication?

    <p>Produces DNA from RNA</p> Signup and view all the answers

    What is a common feature of satellite viruses and satellite nucleic acids?

    <p>They require a helper virus to replicate</p> Signup and view all the answers

    What is the role of capsids in viral replication?

    <p>Act as intracellular machines for transcription</p> Signup and view all the answers

    What is the role of viral structural proteins in the viral replication cycle?

    <p>Encapsidate the newly replicated genome</p> Signup and view all the answers

    Why do viruses need to rely on host cells for survival?

    <p>They lack their own metabolic machinery</p> Signup and view all the answers

    What is the composition of a virion?

    <p>Nucleic acid genome, protective coat, and sometimes a lipid envelope</p> Signup and view all the answers

    What happens to virus particles once inside the host cell?

    <p>Disintegrate and release genetic material</p> Signup and view all the answers

    What is the genetic material of a virus?

    <p>DNA or RNA</p> Signup and view all the answers

    What is the function of a virion's lipid envelope?

    <p>Protects the nucleic acid genome</p> Signup and view all the answers

    What is the main role of viruses' genetic material inside the host cell?

    <p>Direct replication of viral genome using host machinery</p> Signup and view all the answers

    What is the function of the capsid in a virus particle?

    <p>Protects the nucleic acid genome</p> Signup and view all the answers

    What is the role of viral proteins during virus entry into the host cell?

    <p>Facilitate virus entry and uncoating</p> Signup and view all the answers

    What is the function of the lipid envelope in some virions?

    <p>Protects the virion from the host's immune response</p> Signup and view all the answers

    What is the significance of the fact that viruses are considered the simplest and smallest forms of life?

    <p>They lack their own metabolic machinery</p> Signup and view all the answers

    What is the primary function of viral structural proteins?

    <p>Encapsidate the viral genome</p> Signup and view all the answers

    What is the main issue with having an RNA genome?

    <p>The need to synthesize mRNA from an RNA template</p> Signup and view all the answers

    What is the role of reverse transcriptase in retroviruses?

    <p>Converts RNA to DNA in the host cell</p> Signup and view all the answers

    What did the Hershey and Chase experiment demonstrate?

    <p>DNA is the carrier of inheritance information</p> Signup and view all the answers

    What distinguishes viruses from other microorganisms according to early studies?

    <p>Passing through filters made of fine earth or porcelain</p> Signup and view all the answers

    What is the main reason bacteriophages are used as a model system?

    <p>They contain and express genes like other organisms</p> Signup and view all the answers

    Which enzyme is commonly encoded by most RNA viruses?

    <p>RNA dependent RNA polymerase</p> Signup and view all the answers

    What is the significance of viruses in the study of biology?

    <p>Discovery that DNA carries inherited genetic information</p> Signup and view all the answers

    What is the primary role of viruses in various ecosystems?

    <p>Aiding in the understanding of cellular processes</p> Signup and view all the answers

    What was the outcome of the filtration experiment with the agent causing mosaic disease?

    <p>The agent was identified as a virus</p> Signup and view all the answers

    What is the significance of the study of bacteriophages?

    <p>All of the above</p> Signup and view all the answers

    What is the function of bacteriophages in genetic mapping?

    <p>To provide a model for genetic crosses</p> Signup and view all the answers

    What is the significance of the RNA genome in viruses?

    <p>It poses challenges for mRNA synthesis and replication</p> Signup and view all the answers

    Study Notes

    Viral Genome Structure and Evolution

    • Some viruses have segmented or unsegmented genomes
    • dsRNA viruses have fragmented genomes and capsids with icosahedral symmetry
    • Capsids act as intracellular machines for transcription
    • dsRNA viruses tend to have a broad host range
    • Satellite viruses and satellite nucleic acids require a helper virus to replicate
    • Viroids do not encode for proteins and replicate independent of other viruses
    • Viruses may have originated alongside host cells
    • Reverse transcriptase produces DNA from RNA
    • Limited number of viral genes encode for structural proteins and enzymes
    • Viruses have to evade host cell defense barriers and the immune system
    • Bacteriophages and plant viruses have different entry mechanisms than animal viruses
    • Enveloped and non-enveloped viruses have distinct penetration strategies

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Description

    Test your knowledge of viral genome structure and evolution with this quiz. Explore the diversity of viral genomes, replication mechanisms, and interactions with host cells. From segmented genomes to entry mechanisms, this quiz covers key concepts in virology.

    More Like This

    Viral Genome Replication Quiz
    28 questions
    Viral Genome and Capsid Quiz
    18 questions
    Viral Genomes: DNA vs. RNA
    17 questions

    Viral Genomes: DNA vs. RNA

    FastGrowingPeachTree avatar
    FastGrowingPeachTree
    Use Quizgecko on...
    Browser
    Browser