Viral Replication Processes

Reverse transcriptase converts positive sense ss RNA into negative sense ss DNA.

Early proteins are enzymes required for genome replication, while late proteins are structural proteins for progeny viruses.

Viral nucleic acid is incorporated into a capsid to form a mature virion.

<p>The final step is the release of completed viruses from the host cell.</p> Signup and view all the answers

<p>Enveloped viruses release through budding, whereas nonenveloped viruses often cause cell lysis.</p> Signup and view all the answers

<p>Herpes virus buds from the nuclear membrane instead of the outer cell membrane.</p> Signup and view all the answers

<p>The negative sense ss DNA produced is transcribed into viral mRNA by host cell RNA polymerase.</p> Signup and view all the answers

<p>Late viral proteins are mainly structural proteins that assemble the new virions after the genome has been replicated.</p> Signup and view all the answers

<p>Lysosomal enzymes degrade the protein of the viral capsid, facilitating uncoating.</p> Signup and view all the answers

<p>Poxvirus relies on a specific enzyme encoded by the viral DNA for uncoating, while other viruses may utilize host cell enzymes.</p> Signup and view all the answers

<p>Transcribing specific mRNAs is essential for the successful expression and duplication of the viral genetic information.</p> Signup and view all the answers

<p>DNA viruses use the host's RNA polymerase to transcribe mRNA directly from their viral DNA.</p> Signup and view all the answers

<p>Double-stranded RNA viruses transcribe one strand into mRNA using their own viral polymerase.</p> Signup and view all the answers

<p>The CD4 receptor is crucial for HIV's attachment to target cells, determining the virus's ability to infect those cells.</p> Signup and view all the answers

<p>Positive-sense ss RNA viruses can directly use their RNA genome as mRNA without further transcription.</p> Signup and view all the answers

<p>Nonenveloped viruses enter host cells through endocytosis, specifically a process known as viropexis.</p> Signup and view all the answers

<p>Negative-sense ss RNA viruses must transcribe their RNA into a positive-sense strand, which can then act as mRNA.</p> Signup and view all the answers

<p>RNA viruses require their own viral polymerase for transcribing mRNA from their RNA templates.</p> Signup and view all the answers

<p>Uncoating is the process where the viral nucleic acid is separated from its protein core, allowing for replication.</p> Signup and view all the answers

<p>Most DNA virus genome replication occurs in the nucleus, except for Poxviruses, which replicate in the cytoplasm.</p> Signup and view all the answers

<p>RNA viruses generally replicate in the cytoplasm, while retroviruses replicate in the nucleus.</p> Signup and view all the answers

<p>Viral envelope proteins facilitate the fusion of the virus with the host's plasma membrane, allowing the capsid to enter the cell.</p> Signup and view all the answers

<p>RNA viruses have a higher mutation rate due to their error-prone RNA polymerase during replication.</p> Signup and view all the answers

<p>The specific surface receptors on a cell determine the host range, as viruses can only infect cells with compatible receptors.</p> Signup and view all the answers

<p>The Eclipse period is the time during which no virus is found inside the host cell, starting from the penetration stage until mature daughter virions appear.</p> Signup and view all the answers

<p>A single cycle of viral replication typically takes about 15–30 hours.</p> Signup and view all the answers

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

<p>Cytopathic effect (CPE) refers to the alterations in cell morphology and function resulting from viral infection, culminating in cell lysis and death.</p> Signup and view all the answers

<p>The first three steps in the viral replication cycle are recognition of the target cell, attachment of the virus particle to the cell surface, and penetration into the host cell.</p> Signup and view all the answers

<p>During the uncoating stage, the virus sheds its outer layers and capsid to release its genetic material into the host cell.</p> Signup and view all the answers

<p>Viruses are considered obligatory intracellular parasites because they lack the machinery to synthesize their nucleic acids or proteins independently and rely on the host cell's metabolic processes.</p> Signup and view all the answers

<p>The host cell's metabolic machinery is utilized by viruses to synthesize their nucleic acids and proteins necessary for replication.</p> Signup and view all the answers