Viral Uncoating and Gene Expression Quiz

Acidic pH in the endosome is required for uncoating of viruses.

Viruses are the only infectious agents for which dissolution of the infecting agent is an obligatory step in the replicative pathway.

The first step in viral gene expression is mRNA synthesis.

<p>Viral protein is synthesized in the cytoplasm.</p> Signup and view all the answers

<p>Many viral proteins undergo modifications like glycosylation, acylation, and cleavages.</p> Signup and view all the answers

<p>Viral DNA is usually replicated in the nucleus.</p> Signup and view all the answers

<p>The virus disappears</p> Signup and view all the answers

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

<p>The time during which no virus is found inside the cell</p> Signup and view all the answers

<p>The time from the onset of infection to the appearance of virus extracellularly</p> Signup and view all the answers

<p>Reproduction from one virus particle to several hundred virus particles</p> Signup and view all the answers

<p>Alterations of cell morphology and function; culminates in the lysis and death of cells</p> Signup and view all the answers

<p>Lytic cycle involves immediate replication and lysis of the host cell, while lysogenic cycle involves integration of viral DNA into host DNA and remaining dormant until triggered.</p> Signup and view all the answers

<p>T4 bacteriophage</p> Signup and view all the answers

<p>Antiviral therapy is recommended when vaccines are not available, not highly effective, or for constantly changing viruses like influenza and HIV.</p> Signup and view all the answers

<p>Nucleoside and nucleotide analogs inhibit nucleic acid replication by targeting polymerases essential for replication.</p> Signup and view all the answers

<p>Lysogenic phages become active when host conditions deteriorate or under stressful conditions.</p> Signup and view all the answers

<p>Lytic phages are more suitable because they immediately replicate and lyse the host cell, releasing new viruses.</p> Signup and view all the answers

<p>In the cytoplasm</p> Signup and view all the answers

<p>Double stranded DNA</p> Signup and view all the answers

<p>In the cell cytoplasm</p> Signup and view all the answers

<p>In the nucleus of hepatocytes</p> Signup and view all the answers

<p>The process of transcribing gene sequences into functional gene products</p> Signup and view all the answers

<p>The stage at which a virus particle becomes infectious</p> Signup and view all the answers

<p>Inhibit the viral proteases, prevent mature virion core formation, and prevent activation of reverse transcriptase (RT).</p> Signup and view all the answers

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

<p>Fuzeon blocks the virus and cellular membrane fusion step involved in the entry of HIV-1 into cells.</p> Signup and view all the answers

<p>They specifically inhibit influenza A viruses by blocking viral uncoating.</p> Signup and view all the answers

<p>Foscarnet selectively inhibits viral DNA polymerases and reverse transcriptases at the pyrophosphate binding site.</p> Signup and view all the answers

<p>Methisazone was the first antiviral agent described and contributed to the campaign to eradicate smallpox by blocking a late stage in viral replication.</p> Signup and view all the answers

<p>Attachment, penetration, and uncoating</p> Signup and view all the answers

<p>Attachment/Adsorption</p> Signup and view all the answers

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

<p>Gene expression and genome replication</p> Signup and view all the answers

<p>Assembly and release</p> Signup and view all the answers

<p>Receptor molecules</p> Signup and view all the answers

<p>Lysogenic cycle</p> Signup and view all the answers

<p>T4</p> Signup and view all the answers

<p>When vaccines are not available or not highly effective, multiplicity of serotypes exists, or the virus is constantly changing.</p> Signup and view all the answers

<p>Nucleoside and Nucleotide Analogs</p> Signup and view all the answers

<p>To transcribe gene sequences into functional gene products such as proteins or functional RNAs.</p> Signup and view all the answers

<p>Maturation is the stage of viral replication where a virus particle becomes infectious by assembling nucleic acids and capsids together.</p> Signup and view all the answers

<p>Lysogenic phages become active when host conditions deteriorate or stressful conditions arise because the prophage within the host cell proliferates under these circumstances.</p> Signup and view all the answers

<p>They inhibit nucleic acid replication by targeting polymerases essential for replication.</p> Signup and view all the answers

<p>Naked viruses accumulate in infected cells causing host cell lysis, while budding viruses mature by a budding process and may not necessarily kill the cell.</p> Signup and view all the answers

<p>In the nucleus of hepatocytes.</p> Signup and view all the answers

<p>Parvoviruses have a single-stranded DNA genome while other DNA viruses have double-stranded DNA genomes.</p> Signup and view all the answers

<p>Because they replicate in the cytoplasm where they do not have access to the host cell RNA polymerase.</p> Signup and view all the answers

<p>Interferons are host-coded proteins that inhibit viral replication and are produced quickly in response to viral infection as one of the body's first responders in defense against viral infection.</p> Signup and view all the answers

<p>IFNs degrade viral mRNA, inhibit protein synthesis of the virus, and prompt the synthesis of other proteins in the host cell which inhibit viral replication.</p> Signup and view all the answers

<p>The three general groups of IFNs are IFN-α, IFN-β, and IFN-γ. IFN-γ is mainly produced by lymphocytes, especially T cells and NK cells.</p> Signup and view all the answers

<p>RNA viruses are stronger inducers of IFNs than DNA viruses.</p> Signup and view all the answers

<p>IFNs induce the synthesis of other proteins in the host cell which inhibit viral replication.</p> Signup and view all the answers

<p>IFNs enhance MHC class I, II expression to present viral antigens.</p> Signup and view all the answers

<p>Protease Inhibitors (PI) inhibit the viral proteases, prevent mature virion core formation, and prevent activation of reverse transcriptase (RT), resulting in noninfectious virus particles.</p> Signup and view all the answers

<p>Amantadine and Rimantadine inhibit influenza A viruses by blocking viral uncoating, specifically preventing the release of viral genetic material into host cells.</p> Signup and view all the answers

<p>Fuzeon, a large peptide, blocks the fusion step between the virus and cellular membrane, thereby inhibiting the entry of HIV-1 into cells.</p> Signup and view all the answers

<p>Foscarnet, an organic analog of inorganic pyrophosphate, binds selectively to the pyrophosphate binding site of viral DNA polymerases and reverse transcriptases, inhibiting their activity.</p> Signup and view all the answers

<p>Methisazone was the first antiviral agent described and contributed to the campaign to eradicate smallpox by blocking a late stage in viral replication, resulting in the formation of noninfectious poxvirus particles.</p> Signup and view all the answers

<p>Protease Inhibitors (PI) are designed to fit into the active site of the HIV protease enzyme, inhibiting its function and preventing the cleavage of viral polyproteins into functional proteins.</p> Signup and view all the answers