viruses

Question 1

what are the unique properties of viruses

Answer 1

acellular, it is a nucleic acid surrounded by a protein coat, obligate parasite because they do not carry out metabolism and they lack organelles and ribosomes , 20-300 nm in size.

Question 2

what is the impact of these unique properties

Answer 2

cannot self replicate, hard to filter our because of size visualized only with electron microscope

Question 3

what are the components of a virion

Answer 3

nucleid acid surrounded by a capsid, some have an envolope made of lipids

Question 4

what is the importance of the genome of a virus

Answer 4

segmented or continous very diverse RNA or DNA, single or double stranded and the SS RNA can be positive or negative orientation meaning posistive can be translated into a protein directly or negative is inert and cannot.

Question 5

what is the importance of the capsid

Answer 5

protection of the nucleic acid. When within the lipid membrane of the envelope it is called a necleocapsid. Can have different shapes depending on the proteins. Helical one type of protein subunit, icosahedral capsid are made up of regularly repeating patterns of subunits 20 triangular faces making 12 vertices, complex is midification of the regular icosahedral pattern.

Question 6

what is the importance of the envelope

Answer 6

derived from cellular membrane except in poxviruses, contain specific viral proteins embedded in them that aid in entry into target cell, because of envelope they need cellular condition to survive.

Question 7

what virus families go with ss DNA

Answer 7

parovoviridae

Question 8

what virus families go with ds DNA

Answer 8

herpesviridae, poxviridae, hepadnaviridae, adenoviridae, papovaviridae

Question 9

what virus families go with ds RNA

Answer 9

reoviridae

Question 10

what virus families go with -ssRNA

Answer 10

orthomyxoviridae, paramyxoviridae, rhabdoviridae, bunyaviridae, fileviridae, arenaviridae

Question 11

what virus families go with +ssRNA

Answer 11

togaviridae, flaviviridae, coronaviridae, retroviridae, picornaviridae, caliciviridae, hepeviridae

Question 12

what are the genome properties unique to RNA

Answer 12

because RNA is labile and transcient they replicate quickly in cytoplasm, they cannot replicate RNA so they must encode and carry in the virion a RNA polymerase RNA is more prone o mutation.

Question 13

what are the properties of a capsid enclosed virus

Answer 13

more resistant to temp changes detergents ect released by lysis

Question 14

what are the steps in a virus life cycle

Answer 14

attachment entry mRNA protein and genome synthesis, Virion assembly, egress/leave cell.

Question 15

what are the two modes of entry for a virus

Answer 15

direct fusion in envoloped cells causing multinucleated cells, second it can use cell receptors causing invagination causing two membrans around capsid. This is also the method for non enveloped cells

Question 16

how do -ssRNA and dsRNA produce mRNA

Answer 16

by using also having an RNA dependent RNA polymerase in the virion particle

Question 17

how does the Papovavairses get around making its own genome

Answer 17

stimulate cell growth to th s phase so machinary is ready

Question 18

how does the poviruses get its DNA genome made

Answer 18

it carries everything needed to create its own machinary

Question 19

viral recombination only works for what type of viruses

Answer 19

double stranded DNA viruses

Question 20

what is reassortment

Answer 20

when both infect a cell the varions can mixing up segements of the segmented viruses influenza

Question 21

what is a plaque assay

Answer 21

add virus to cells on plaque look for them to die and be cleared on the plaque

Question 22

what does an elisa assay

Answer 22

antibodies used to look for the virus antigens or the bodies antigens to the virus using western blot