DNA and RNA Virus Replication Quiz

Questions and Answers

What type of virus is categorized as Type I?

Double stranded RNA

Double stranded DNA genome

Single stranded RNA

Double stranded DNA (correct)

Type II viruses are characterized by having double stranded RNA.

False

What is the replication process for Type III viruses?

dsRNA --> ssRNA --> dsRNA

Which type of virus has a genome that acts directly as mRNA?

Type IV Signup and view all the answers

What type of viruses are characterized by a (-) sense single stranded RNA?

Type V Signup and view all the answers

Which virus type must package reverse transcriptase with its genome?

Type VI Signup and view all the answers

What is an example of a Type VII virus?

Hepatitis B Signup and view all the answers

Study Notes

Type I: Double Stranded DNA

Replication cycle: dsDNA replicates to dsDNA.
mRNA synthesis: dsDNA translated to mRNA.
Utilizes DNA-dependent DNA polymerase.
In eukaryotes, replication occurs in the nucleus; in prokaryotes, it takes place in the cytoplasm.
Example viruses include HPV and herpes.

Type II: Single Stranded DNA

Replication cycle: ssDNA converts to dsDNA before returning to ssDNA.
mRNA synthesis: ssDNA to dsDNA, then to mRNA.
Relies on host DNA polymerase to create complementary DNA.
In eukaryotes, processes occur in the nucleus; in prokaryotes, they occur in the cytoplasm.
Example: Parvovirus, which can cause serious illness in dogs.

Type III: Double Stranded RNA

Replication cycle: dsRNA transforms into ssRNA before reverting to dsRNA.
mRNA synthesis: dsRNA directly gives rise to mRNA.
Requires RNA-dependent RNA polymerase for replication.
In both eukaryotes and prokaryotes, processes unfold in the cytoplasm.
Example virus: Rotavirus, a leading cause of diarrhea in infants.

Type IV: (+) Sense Single Stranded RNA

Replication cycle: +RNA converts to -RNA and back to +RNA.
mRNA synthesis: +RNA functions as mRNA.
Uses RNA-dependent RNA polymerase for replication in the cytoplasm of both eukaryotes and prokaryotes.
The RNA genome directly serves as mRNA for protein synthesis.
Example: Poliovirus.

Type V: (-) Sense Single Stranded RNA

Replication cycle: -RNA converts to +RNA, then back to -RNA.
mRNA synthesis: -RNA transcribes into mRNA.
Requires RNA-dependent RNA polymerase for replication within the cytoplasm of both eukaryotes and prokaryotes.
The genomic RNA does not act as mRNA directly; it is transcribed into a complementary strand.
Example viruses include influenza and Ebola.

Type VI: (+) Sense Single Stranded RNA with Retroviruses

Replication cycle: ssRNA is converted into dsDNA and returns to ssRNA.
mRNA synthesis: ssRNA transcribes to dsRNA and then to mRNA.
Utilizes reverse transcriptase (RNA-dependent DNA polymerase) for replication.
In eukaryotes, procedures happen in the nucleus; in prokaryotes, they occur in the cytoplasm.
Must package reverse transcriptase with the genome for infection.
Associated with oncogenic capabilities in some retroviruses, like FeLV.
Example: HIV.

Type VII: Gapped Double Stranded DNA

Replication cycle: gapped dsDNA converts to dsDNA, then to +RNA and -DNA before reverting to gapped dsDNA.
mRNA synthesis: gapped dsDNA transcribes into dsDNA and then to mRNA.
Relies on multiple polymerases: DNA-dependent DNA polymerase, DNA-dependent RNA polymerase, and RNA-dependent DNA polymerase.
Employs reverse transcriptase during replication.
Example: Hepatitis B virus.

Description

Test your knowledge on the replication cycles of various types of viruses, including double-stranded and single-stranded DNA and RNA viruses. This quiz covers key concepts such as replication, mRNA synthesis, and examples of viral illnesses. Perfect for biology students focusing on virology.