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Flashcards in Micro 19 - Viral Basics Deck (28)
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Which types of viruses are part of the non-eveloped RNA virus?

Calicivirus, Picornavirus, Reovirus, Hepevirus.


What structural element does enveloped viruses have that noneveloped (naked) viruses do not have? Which is more resistant to the elements?

The enveloped virus has a lipid bilayer that is usually from the host's cell bilayer. The naked virus does not have that, but is more resistant to the elements.


What are four important non-enveloped RNA virus Family?

Calicivirus, Picornavirus, Reovirus, Hepevirus.


What are four important non-enveloped DNA virus family?

Parvovirus, Adenovirus, Papillomavirus, Polyomavirus.


DNA virus usually replicate in the nucleus. However, where do pox virus family replicate?

In the cytoplasm.


Most of the RNA virus replicate in the cytoplasm, however which two viruses replicate in the nucleus?

Influenza virus and the retrovirus.


What is reassortment?

Non-classical recombination that occurs with virus with segmented genome, which only include RNA virus (That only infect humans); when two viruses are infecting the same cell, they can exchange genetic segments. This happens with the influenza virus.


What is viral recombination?

When two virus infect the same cell; this cohabitation allows genes to be exchange from two different chromosomes, making progeny that is only their parents. This usually occurs with DNA virus or RNA virus with a DNA phase like retrovirus.


What is Viral complementation?

When two viruses infect the same cell, but one of them has a mutation that leads to a non-functioning protein; in some cases the other virus might make the necessary protein so both can replicate. However, the progeny of the defective virus will still have that non-functioning virus therefore it's only hope in the next cell that it infects is to infect it with that other virus.


What is Phenotypic mixing?

When two different virus infect the same cell, but when the progeny are created, they might receive surface protein from both virus that are infecting the same cell. However, the genetic material has not been mixed (not changed at all).


What is the virus ploidy?

Viruses are haploid; 1 copy of DNA or RNA. Except retroviruses that have2 copies of single stranded RNA (ssRNA).


Which virus has single stranded DNA?



Which three viruses have circular DNA?

Papillomavirus and Polymavirus have circular virus. Hepadnavirus has partially circular genome.


How is the genomic structure of most DNA virus?

Most DNA virus are double stranded DNA and have linear DNA.


How is the genomic structure of RNA viruses?

Most RNA viruses are single stranded RNA.


Which two RNA viruses have dsRNA?

Reovirus and Rotavirus have double stranded RNA.


Most of RNA of RNA virus are plus strands. What does that mean?

It means that they are in positive sense, there they can start making proteins right away. They do not need to wait for a complementary strand to make proteins.


Which RNA viruses have positive (plus) strand RNA?

Retrovirus, Togavirus, Flavivirus, Coronavirus, Hepevirus, Calicivirus, Picornavirus.


What is the infectivity for naked virus?

Most dsDNA viruses and positive ssRNA viruses can infect cells just using their naked genome.


What are 7 DNA virus families?

Herpesvirus, Hepadnavirus, Adenovirus, Parvovirus, Papillomavirus, Polymavirus, Poxvirus.


Most DNA virus are icosahedral. Which one isnt?



What are four DNA virus characteristics?

Double stranded, linear genomes, icosahedral, replicate in the nucleus.


Which are the 8 live attenuated vaccines?

Smallpox, Yellow fever, Chicken pox (varicella), MMR, Sabine polio vaccine (oral), Herpes zoster vaccine, Intranasal influenza, rotavirus.


What are the four killed virus vaccines?

Injectable influenza, Rabies, Hepatitis A, Injectable Salk polio.


Which vaccines are grown on chicken eggs? What do we do for each case of egg allergy?

Influenza, yellow fever, MMR vaccines. For influenza, give them if they do not have anaphylactic response to egg. For yellow fever, there must be skin testing and desensitization. For MMR, no contraindication (just give it).


Which of the live virus vaccine be considered in HIV patients?

Rotavirus recommended for all infants with HIV. MMR and varicella for CD4 count more than 200. Live virus influenza and herpes zoster are nor recommended at any CD4 count.


Where does Herpes virus acquire its envelope?

Most virus get it from host plasma membrane but herpes virus gets it from Nuclear membrane.


What are 8 naked viruses?

Adenovirus, Calicivirus, Papilloma, Parvovirus, Picornavirus, Polyomavirus, Reovirus, Hepevirus.