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Microbiology > Chapter 13- Viruses (EXAM 2) > Flashcards

Chapter 13- Viruses (EXAM 2) Flashcards

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1
Q

Where do viruses replicate?

A

only inside host cells

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2
Q

What two phases do viruses exist in?

A

A virus exists in two phases: intracellular (infected cell) where it is ‘alive,’ and extracellular (virion particle) where it is inactive.

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3
Q

How do viruses differ from bacteria?

A

Viruses are tinier than bacteria. All viruses have is a protein coat and a core of genetic material, either RNA or DNA. Unlike bacteria, viruses can’t survive without a host. They can only reproduce by attaching themselves to cells.

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4
Q

Are viruses living?

A

no

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5
Q

multiply inside living cells by using the energy,

metabolites, and biosynthetic machinery of the cell

A

obligatory intracellular parasites

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6
Q

do viruses make energy or ATP?

A

no

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7
Q

viruses are enclosed in a protein coat called a _______

A

capsid

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8
Q

Some viruses have a ______ envelope

A

lipid

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9
Q

Do viruses pass through a bacteriological filter?

A

yes

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10
Q

What are viruses made of?

A

a nucleic acid genome and a protein capsid or coat

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11
Q

virus nucleic acid is one molecule or several (__________ or _________)
much, much smaller than a single human chromosome

A

segmented or unsegmented

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12
Q

the genome plus the capsid

A

nucleocapsid

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13
Q

some viruses contain no __________

A

viral membranes (envelopes)

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14
Q

Some viruses also contain:

A 
envelope or viral membrane
taken from the host cell
membrane proteins
some encoded by the virus
some belonging to the host
polymerase
RNA polymerase or DNA polymerase
other virus-encoded proteins
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15
Q

How small are bacteriophages T4 and M13? and MS2

A

225nm; 800*10 nm; 24 nm

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16
Q

How small are adenovirus?

A

90 nm

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17
Q

how small are rhinovirus?

A

30 nm

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18
Q

How small are prions?

A

20 *20 nm

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19
Q

how small are vaccinia virus?

A

300200 100 nm

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20
Q

how small are viroid?

A

300 * 10 nm

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21
Q

how small is ebola virus?

A

970 nm

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22
Q

how small is an E.coli bacterium?

A

3000*1000 nm

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23
Q

how small is rabies virus?

A

170 * 70 nm

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24
Q

how small is rabies virus?

A

170 * 70 nm

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25
Q

How could the small size of viruses have helped researchers detect viruses before the invention of the electron microscope?

A

Filterable agents

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26
Q

What is the resolution on a light microscope?

A

0.2 microns or 200 nanometers

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27
Q

What is the resolution on a transmission electron microscopy?

A

0.2 nanometers

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28
Q

What is the X-ray crystallography?

A

0.05 nanometers, 0.5 angstrom

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29
Q

Where was the first electron microscope made?

A

In camden nj

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30
Q

What are the different virus shapes?

A

polyhedral w/ spikes or no spikes
helical
complex

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31
Q

A virus can be __________ or ___________

A

enveloped or non-enveloped

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32
Q

Examples of polyhedral viruses

A

mastadenovirus

poliovirus

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33
Q

What are the components of a simple polyhedral virus?

A

capsomere (makes up a capsid), nucleic acid

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34
Q

What is an icosahedron?

A

20 sides

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35
Q

What is a pentakis dodecahedron?

A

60 sides

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36
Q

What is the envelope made up of?

A

lipids, proteins, and carbohydrates

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37
Q

How do viruses multiply

A

by using the host cell’s synthesizing machinery to cause the specialized elements that can transfer the viral nucleic acid to other cells

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38
Q

What is host range?

A

the spectrum of host cells in which a virus can multiply

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39
Q

Most viruses infect only specific types of _______ in one host species

A

cells

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40
Q

What is the host range determined by?

A
  1. the specific attachment site on the host cell’s surface

2. the availability of the host cellular factors

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41
Q

What is viral size ascertained by?

A

electron microscopy

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42
Q

What is the virus range in size?

A

20 to 1000 nm in length

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43
Q

What is a virion?

A

a complete, fully developed viral particle composed of nucleic acid surrounded by a coat

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44
Q

The proportion of nucleic acid in relation to protein in viruses ranges from about ___% to about ____%

A

1; 50

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45
Q

the protein coat surrounding the nucleic acid of a virus

A

capsid

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46
Q

The capsid is composed of subunits, __________, which can be single type of protein or several types

A

capsomeres

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47
Q

The capsid of some viruses is enclosed by an envelope consisting of _______, ________, and ___________.

A

lipids, proteins, and carbohydrates

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48
Q

Some envelopes are covered with carbohydrate-protein complexes called _________

A

spikes

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49
Q

example of helical viruses

A

ebola virus

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50
Q

resemble long rods, and their capsids are hollow cylinders surrounding the nucleic acid

A

helical viruses

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51
Q

example of polyhedral viruses

A

adenovirus

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52
Q

are many sided and the capsid is icosahedron

A

polyhedral viruses

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53
Q

example of an enveloped polyhedral virus

A

herpesvirus simplexvirus

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54
Q

where does the virus envelope come from?

A

the host

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55
Q

Enveloped viruses are covered by an envelope and are roughly spherical but highly _________.

A

pleomorphic

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56
Q

example of an enveloped helical virus

A

influenzavirus

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57
Q

What are the viral surface proteins on influenza viruses?

A 
Hemmaglutinin (HA) 
and Neuraminidase (NA)
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58
Q

complex viruses have complex structures. For example many __________ have a polyhedral capsid with a helical tail attached.

A

bacteriophages

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59
Q

What are the viral surface proteins on HIV? What are their purposes?

A

gp120- docking glycoprotein

gp41- transmembrane glycoprotein

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60
Q

What specific enzyme is important to HIV?

A

reverse transcriptase

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61
Q

HIV has more surface molecules from the _____ ______ than molecules by the _______ ________

A

host cell; virus genome (encoded)

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62
Q

What are some examples of complex viruses?

A

poxvirus, orthopoxvirus, and bacteriophages

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63
Q

a transmembrane fusion protein. Forms trimers on the virion surface and mediates virus attachment and entry into the host cell

A

GP

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64
Q

What human proteins are found on the viral membrane of Ebola? What is the purpose of this?

A

histocompitability (HLA) proteins or other surface receptors, which
in some cases can increase the infectivity of the enveloped viruses.

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65
Q

How do similar viruses differ from each other?

A

variations on surface proteins

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66
Q

How many subtypes (variations of surface proteins) does influenza A have?

A

17 different subtypes of HA, 10 of NA

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67
Q

How many subtypes (variations of surface proteins) does poliovirus have?

A

3 different serotypes

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68
Q

How many subtypes (variations of surface proteins) does rhinovirus have?

A

100 different serotypes

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69
Q

How are viruses classified?

A
  1. nucleic acid
  2. strategy for replication
  3. morphology
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70
Q

What do virus families end with? What do genus names end with?

A

family: -viridae
genus: -virus

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71
Q

What is a viral species?

A

a group of viruses sharing the same genetic information and ecological niche

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72
Q

What is the HIV cell surface receptor and co-receptor?

A

CD4 = receptor, CXCR4 = co-receptor

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73
Q

Where do viruses grow and develop?

A

in living cells

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74
Q

what are the easiest viruses to grow?

A

bacteriophages

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75
Q

What is the plaque method?

A

the plaque method mixes bacteriophages with host bacteria and nutrient agar. After several viral multiplication cycles, the bacteria in the area surrounding the original virus are destroyed: the area of lysis is called a plaque.

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76
Q

How do viruses infect?

A

Viruses have cell surface receptors that recognize human cells and bind to their surface proteins

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77
Q

What is the cell surface molecule for E.coli?

A

maltoporin (lambB) phage lambda

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78
Q

What is the cell surface molecule for Influenza?

A

Influenza HA protein binds sialic acid

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79
Q

Different ___ proteins of Influenza A bind different forms of _______ acid

A

sialic

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80
Q

What does tropism mean?

A

“tropism” means roughly “what the virus is able to infect

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81
Q

the range of different

species a virus can infect

A

Host range (or host tropism):

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82
Q

the types of different tissues in an individual a virus can infect

A

tissue tropism

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83
Q

What determines host range and tissue tropism?

A

specific host attachment sites: due to differences in surface proteins intracellular factors
intracellular factors: host enzymes and antiviral defenses

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84
Q

Measles first infects immune system cells in the lung via the receptor _______. It then travels via these traveling cells to infect a variety of ________ cells via the receptor ________ 4.

A

SLAM; epithelial; Nectin

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85
Q

Each plaque originates with a ________ ______ ________; the concentration of viruses is given a ______-_________ _______

A

single viral particle; plaque-forming units

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86
Q

________ ______ of the immune system deliver ____ to lymph nodes where they infect T cells, which lead to sever decline in immune system function

A

Dendritic cells (DCs); HIV

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87
Q

Which virus has a broad host range?

A

influenza viruses, Ebola viruses

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88
Q

Which virus has a small host range?

A

poliovirus, has a host range of one species

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89
Q

How was Ebola virus introduced to the human population via its natural hosts (fruit bats).

A

close contact with the blood, secretions, organs or other bodily fluids of infected animals such as chimapanzees, gorillas, fruit bats, monkeys, forest antelope, and porcupines found ill or dead or in the rainforest

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90
Q

The virus surface proteins determine what ______ ________ _________ the virus uses.

A

cell surface

receptors

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91
Q

What cells the surface receptors are on determines

______ _______, thus the pathology.

A

tissue tropism

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92
Q

Variation in cell surface receptors determine the _____ _______, that is, what species can be infected.

A

host range

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93
Q

Variation in virus surface proteins determine the

effectiveness of the _____ _______ ______.

A

host immune response

94
Q

Where do intracellular restrictions to viral growth occur?

A

Restrictions to virus tropism are not just at the surface
of the cell, but can occur at virtually any step of virus
replication, maturation, and release from the cell

95
Q

Viruses that belong to the Herpesviridae family (genus and species)

A

Herpesvirus (genus)

Human herpes virus HHV-1, HHV-2, HHV-3

96
Q

Viruses that belong to the Picornaviridae family (genus and species)

A

Enterovirus (genus)

Poliovirus

97
Q

Viruses that belong to Retroviridae (genus and species)

A

Lentivirus (genus)

Human immunodeficiency virus HIV-1, HIV-2

98
Q

SS DNA non enveloped virus family

A

parvovirdae

99
Q

DS DNA non enveloped viruse family

A

adenovirus

papovaviridae

100
Q

DS DNA enveloped virus family

A

poxviridae
herpesviridae
hepadnaviridae

101
Q

SS RNA + strand nonenveloped virus family

A

picornavirdae

caliciviridae

102
Q

SS RNA + strand enveloped virus family

A

togaviridae
flaviviridae
coronaviridae

103
Q

SS RNA - strand virus family

A

rhabdoviridae
filoviridae
paramyxoviridae
deltaviridae

104
Q

RNA - strand (multiple) virus family

A

Orthomyxoviridae
Bunyaviridae
arenaviridae

105
Q

virus family that makes DNA

A

retroviridae

106
Q

DS RNA nonenveloped virus family

A

Reoviridae

107
Q

Group I, give examples

A

I. double-stranded DNA

enveloped poxvirus, herpesvirus

non-enveloped adenovirus, papovavirus

108
Q

Group II, give examples

A

II. single-stranded DNA, all non-enveloped parvovirus

109
Q

Group III, give examples

A

III. double-stranded RNA, all non-enveloped reovirus

110
Q

Group IV, give examples

A

IV. plus or positive (+) stranded RNA

enveloped flavivirus, togavirus, coronavirus

non-enveloped picornavirus, calicivirus

111
Q

Group V, give examples

A

V. minus or negative (–) stranded RNA, all
enveloped

one RNA molecule rhabdovirus, filovirus, paramyxovirus

multiple RNA molecules orthomyxo-, bunya-, arenavirus

112
Q

Group VI, give examples

A

retroviruses (single-stranded RNA to DNA) enveloped

113
Q

Group VII, give examples

A

hepadnaviruses (dsDNA to RNA to dsDNA) enveloped

114
Q

what does reverse transcriptase do?

A

RNA to DNA

115
Q

What is the genome size of: humans (Chr. 1)

A

3x10^9 bp- human

2.5x10^8 bp- Chr. 1

116
Q

What is the genome size of: yeast

A

1x10^7 bp

117
Q

What is the genome size of: E.coli

A

4 x 106 bp

118
Q

What is the genome size of: HIV

A

9700 nt

119
Q

Which viral genomes are circular?

A

a dsDNA virus

120
Q

Which viral genomes are linear?

A

+ strand RNA

121
Q

__________ ______ ______ can’t be translated. It is first copied into ____ strands

A
  • strand viral RNA; +
122
Q

Which viral genomes are segemented?

A
  • strand RNA
123
Q

Which proteins are encoded by segments?

A

flu HA and NA encoded by segments

124
Q

How are viruses grown in a laboratory? (bacteria, fungi, animals, plants etc.)

A

Viruses must be grown in living cells
bacteria for bacteriophages
fungi for fungal viruses
animals, animal tissues, or cultured animal cells
for animal viruses
plants or cultured plant cells for plant viruses

125
Q

Describe the process of growing animal and plant viruses in cell culture

A
  1. tissue is treated with enzymes to separate the cells
  2. cells are suspended in culture medium
  3. normal cells or primary cells grow in a monolayer across the glass or plastic container. Transformed cells or continuous cell cultures do not grow in a monolayer
126
Q

Animal viruses may be grown in _______ _______ or in __________ _______

A

living animals; embryonated eggs

127
Q

What are some laboratory animal hosts for viruses?

A 
mice
rabbits
guinea pigs
cats
rhesus macaque monkeys
chimpanzees
128
Q

How are viruses identified in the lab?

A 
Pathology
Culture conditions
Serological tests
antibodies against viruses in a patient
Use antibodies to identify viruses in neutralization
tests, viral hemagglutination, and Western blot
Nucleic acids
PCR
sequencing
129
Q

Describe the lytic cycle of a T-even bacteriophage

A
  1. attachment: phage attaches to host cell
  2. penetration: phage penetrates host cell and injects its DNA
  3. Biosynthesis: phage DNA directs synthesis of viral components by the host cell
  4. maturation: viral components are assembled into virions
  5. host cell lyses, and new virions are released
130
Q

Phage attaches by tail fibers to host cell

A

attachment

131
Q

Phage lysozyme opens cell wall; tail sheath contracts to force tail core and DNA
into cell

A

penetration

132
Q

Production of phage DNA and proteins

A

biosynthesis

133
Q

Assembly of phage particles

A

maturation

134
Q

Phage lysozyme breaks cell wall

A

release

135
Q

What is generalized transduction?

A

the virus carries a
random gene or genes
from a host
to another host

136
Q

Phage causes lysis and death of host cell

A

lytic cycle

137
Q

Prophage DNA incorporated in host DNA

A

lysogenic cycle

138
Q

Which cycle can give rise to phage conversion and specialized transduction?

A

lysogenic cycle

139
Q

Describe the lysogenic cycle

A
  1. phage attaches to the host cell and injects DNA
  2. The phage DNA circularizes and enters lytic cycle or lysogenic cycle
    3A. New phage DNA and proteins are synthesized and assembled into virions
    4A. The cell lyses, releasing phage virions
    3B. Phage DNA integrates within the bacterial chromosome by recombination, becoming a prophage
    4B. Lysogenic bacterium reproduces normally
  3. Occassionally the prophage may excise from the bacterial chromosome by another recombination event, initiating a lytic cycle
140
Q

The ________ integrates at a specific sequence,

a single spot, in the bacterial chromosome.

A

prophage

141
Q 
the virus carries a
specific gene or set of
neighboring genes
from a host
to another host based
on where the \_\_\_\_\_\_\_\_
integrated
A

prophage

142
Q

describe the process of specialized transduction

A
  1. prophage exists in galactose-using host (containing the gal gene)
  2. phage genome excises, carrying with it the adjacent gal gene from the host.
  3. Phage matures and cell lyses, releasing phage carrying gal gene
  4. Phage infects a cell that cannot ulitize galactose (lacking gal gene)
  5. Along with the prophage the bacterial gal gene becomes integrated into the new host’s DNA
  6. Lysogenic cell can now metabolize galactose
143
Q

does not require lysogeny
as bacterial genome is degraded some is packaged into
phage head
can transduce virtually any gene in chromosome

A

generalized transduction

144
Q

requires lysogeny, integration of phage DNA into bacterial
chromosome
prophage excises imperfectly, taking nearby DNA with it
limited to the few genes surrounding integration site

A

specialized transduction

145
Q

the bacterium has a new

property due to the presence of the prophage

A

phage conversion

146
Q

Provide an example of when a phage conversion by phage infection might be useful for the bacterium?

A

For example, a disease-causing bacterium may produce a
toxin encoded on a gene in the prophage
Another example: the prophage makes the cell “immune”
to infection by similar phages due to the expression of the
phage repressor protein

147
Q

what are some differences between bacteriophage and animal virus multiplication?

A

Bacteriophage: the viral DNA is injected into the host cell. Lyses the cell.

Animal virus: endocytosis or fusion of the virus is how it gets into the cell. Latency is how animal viruses lead to chronic infection.

148
Q

Describe the process of multiplication of animal viruses

A 
Attachment
Penetration 
Uncoating 
Biosynthesis
Maturation
Release by budding
149
Q

Viruses attach to cell membrane

A

attachment

150
Q

by endocytosis or fusion

A

penetration

151
Q

by viral or host enzymes

A

uncoating

152
Q

Production of nucleic acid and proteins

A

biosynthesis

153
Q

Nucleic acid and capsid proteins

assemble

A

maturation

154
Q

by budding (enveloped viruses) or rupture

A

release

155
Q

How does togavirus enter the cell?

A

pinocytosis

156
Q

How does herpes virus enter the cell?

A

fusion

157
Q

normally, mammalian cells have what type of polymerases

A

DNA dependent DNA polymerase

DNA dependent RNA polymerase

158
Q

A mammalian cell lacks what type of polymerase?

A

RNA dependent DNA polymerase

RNA dependent RNA polymerase

159
Q

make DNA from DNA,

A

it uses the host’s DNA-dependent DNA polymerase

unless it is a cytoplasmic virus, then it uses its own

160
Q

make RNA from DNA,

A

it uses the host’s RNA polymerase

unless it’s cytoplasmic

161
Q

make RNA from RNA,

A

if it is a + strand virus, it can encode its own polymerase

if it is a – strand virus, it must bring in its own polymerase

162
Q

make DNA from RNA,

A

it brings in its own reverse transcriptase

163
Q

ssDNA: what/where viral nucleic acid synthesis

A

cellular enzyme, nucleus

164
Q

dsDNA: what/where viral nucleic acid synthesis (include exceptions)

A

cellular enzyme, nucleus
except poxvirus: viral enzyme, cytoplasm
except hepadnavirus: cell enzyme, nucleus, then…
− RT converts DNA to RNA to DNA

165
Q

RNA: what/where viral nucleic acid synthesis (include exceptions)

A

viral enzyme in cytoplasm
except retrovirus: RT converts DNA to RNA to DNA
−DNA goes to nucleus to integrate

166
Q

Describe the process of multiplying DNA viruses

A
  1. virion attaches to host cell
  2. virion enters cell, and its DNA is uncoated
  3. a portion of viral DNA is transcribed, producing mRNA that encodes “early” viral proteins
  4. viral DNA is replicated, and some viral proteins are made
  5. Late translation; capsid proteins are synthesized
  6. virions are mature
  7. virions are released
167
Q

a normal mRNA transcript is made from a ___________ and it is a ____ sense strand

A

dsDNA molecule; + (slide 120)

168
Q

Describe how a virion is made + strand RNA virus

A

PICORNAVIRIDAE

  1. attachment
  2. entry and uncoating
    - strand is transcribed from a viral + genome
    - mRNA is transcribed from the - strand
  3. RNA replication by viral RNA dependent RNA polymerase
  4. translation and synthesis of viral proteins
  5. maturation and release
169
Q

Describe the process of making a virion from an antisense strand (- strand) RNA virus (provide example)

A

RHABDOVIRIDAE
1. attachment
2. entry and uncoating
(The + strand mRNA must first be transcribed from the - viral genome before proteins can be synthesized)
3. RNA replication by viral RNA dependent RNA polymerase
4. 4. translation and synthesis of viral proteins
5. maturation and release

170
Q

Describe the process of making a virion from a dsRNA virus (provide example)

A

REOVIRUS
1. attachment
2. entry and uncoating
mRNA is produced inside the capsid and released into the cytoplasm of the host
RNA polymerase initiates production of - strands. The mRNA and - strands form the dsRNA that is incorporated as new viral genome
3. RNA replication by viral RNA dependent RNA polymerase
4. 4. translation and synthesis of viral proteins
5. maturation and release

171
Q

Describe multiplication of RNA - containing viruses

A

slide 124

172
Q

Describe multiplication of retroviruses

A

slide 125

173
Q

draw the table (13.4) The Biosynthesis of DNA and RNA viruses compared

A

slide 126 and 127

174
Q

has a low error rate

A

dna synthesis

175
Q

can “proofread” and the cell has _____-repair mechanisms

A

dna; dna polymerase

176
Q

has a high error rate

A

rna synthesis

177
Q

cannot proofread

No known _____ repair mechanism is known

A

RNA; rna polymerase

178
Q

_____ viruses produce more variants per

replication cycle than _____ viruses

A

RNA; DNA

179
Q

An enveloped virus that buds

A

alphavirus

180
Q

Describe the steps to budding in an enveloped virus

A
  1. viral glycoproteins are pushed on by the viral capsid
  2. cross section host cytoplasmic membrane starts to come together
  3. The viral capsid is almost completely enveloped
  4. the enveloped virus buds off
  5. an enveloped virion forms
181
Q

What is a latent viral infection? What is an example of a latent viral infection?

A

virus remains in asymptomatic host cell for long periods. Cold sores (HSV-1 and 2), shingles (herpesvirus), leukemia (HTLV-1 and 2)

182
Q 
Disease
processes
occurs over a
long period;
generally is fatal
A

persistent viral infections

183
Q

examples of persistent viral infections

A

subacute sclerosing panencephalitis (measles virus), cervical cancer (HPV), HIV/AIDS (HIV-1 and 2- lentivirus), Liver cancer (Hepatitis B), Persistent enterovirus infection (Echoviruses), Progressive encephalitis (rubella virus)

184
Q

transform normal cells into

cancerous cells

A

activated oncogenes

185
Q

a process like __________ __________ (involving mRNA)
a process like __________ (involving a provirus)
viral activation of oncogenes not common in humans

A

generalized transduction; lysogeny

186
Q

The genetic material of oncogenic viruses becomes

__________ into the host cell’s DNA

A

integrated

187
Q

__________ cells have increased growth, loss of
contact inhibition, _______-________ transplant
antigens, and ___ antigens

A

transformed; tumor-specific; T

188
Q

What type of viruses are oncogenic viruses usually?

A

DNA viruses

189
Q

How are oncogenes activated by provirus?

A

slide 139

190
Q

Examples of oncogenic DNA viruses

A 
herpesviruses
− EBV
papovaviruses
− HPV
hepadnaviruses
− HBV
191
Q

Examples of oncogenic RNA viruses

A

retroviruses
− HTLV-1
− HTLV-2

192
Q

Only about ___% of human cancers are attributable

to viruses.

A

12

193
Q

what are the most common virus-associated cancers?

A 
cervical cancer (HPV) 
liver cancer (hep B and hep C)
194
Q

− HPV types ___ and ___ cause 70% of cervical cancers

A

16 and 18

195
Q

Are virus-associated cancers preventable? How?

A

Yes, HPV and liver cancer are preventable with vaccination.

Girls and boys, age 11-26, should be vaccinated with a vaccine against four HPV serotypes, including HPV16.

196
Q

What are some viral proteins that promote cancer?

A

SV40 a papovavirus

T antigen
causes
transformation of
cells into cancer
cells
197
Q 
not viruses
naked, infectious RNA
require viruses to spread them
encodes no proteins
only in plants
only similar thing in humans is
Hepatitis Delta
A

viriods

198
Q

What is Chrysanthemum chlorotic mottle viroid?

A

slide 145

199
Q

Hep delta encodes one protein, what is it?

A

the delta antigen (slide 146)

200
Q

Proteinaceous Infectious particle
Inherited and transmissible by ingestion,
transplant, and surgical instruments
Spongiform encephalopathies: Sheep scrapie,
Creutzfeldt-Jakob disease, GerstmannSträussler-Scheinker
syndrome, fatal familial
insomnia, mad cow disease
resemble viruses epidemiologically,
but are not viruses molecularly.

A

prions

201
Q

Describe the process by which prions can be infectious

A

slide 148

202
Q

What are the two forms of prion proteins?

A

a) PrPC

b) PrPSc

203
Q

How do refolded prion proteins recruit other prion

proteins to refold?

A

slide 150

204
Q

class I

A

dsDNA (enveloped and nonenveloped)

enveloped poxvirus, herpesvirus
non-enveloped adenovirus, papovavirus

205
Q

class II

A

ssDNA (all non-enveloped)

Parvovirus

206
Q

class III

A

dsRNA, all non-enveloped

Reovirus

207
Q

class IV

A

plus strand RNA (enveloped and nonenveloped)

enveloped flavivirus, togavirus, coronavirus
non-enveloped picornavirus, calicivirus

208
Q

class V

A

minus strand RNA (all enveloped- one RNA molecule or multiple)

one RNA molecule rhabdovirus, filovirus, paramyxovirus
multiple RNA molecules orthomyxo-, bunya-, arenavirus

209
Q

class VI

A

retroviruses (ss RNA to dsDNA)

210
Q

class VII

A

hepadnaviruses (dsDNA to RNA to dsDNA)

211
Q

structure: very large, complex virion
envelope: yes
genome: double-stranded DNA, linear (145-290 kbp)
example: Vaccinia
species: human
tissue: broad, but especially immune system
disease: none, it is a vaccine against Variola (________)

A

poxviruses; smallpox

212
Q

structure: medium size, polyhedral virion
envelope: yes
genome: double-stranded DNA, linear (100-200 kbp)
example: HSV Type 1
species: human
tissue: broad: epithelia, fibroblasts, neurons
disease: ________

A

herpes

213
Q

structure: large, polyhedral virion
envelope: no
genome: double-stranded DNA, linear (26-45 kbp)
example: ________ _________ Serotype 14
species: human
tissue: respiratory epithelia
disease: acute respiratory disease

A

Human adenovirus (adenoviruses)

214
Q

structure: small polyhedral virion
envelope: no
genome: double-stranded DNA, circular (5-8 kbp)
example: ______ _______ ________
species: human
tissue: keratinocytes of skin and mucous membranes
disease: warts, cancers, particularly cervical cancers
(Vaccinate girls and boys!)

A

HPV (Papovaviruses)

215
Q

structure: very small icosahedral virion
envelope: no
genome: single-stranded DNA, linear (5 kb)
example: Canine _________
species: dogs, wolves, foxes, cats
tissue: gut, lymphatic system
disease: vomiting, diarrhea and immunosupression

A

parvovirus

216
Q

structure: polyhedral virion
envelope: yes
genome: double-stranded RNA
example: _________
species: human
tissue: gastrointestinal tract
disease: severe gastroenteritis in children

A

rotavirus

reoviruses

217
Q

structure: polyhedral virion
envelope: yes
genome: plus strand RNA (10-20 kbp)
example: __________
species: human
tissue: broad: respiratory tract, spleen, lymph nodes
disease: “German measles”

A

rubella (togaviruses)

218
Q

structure: polyhedral virion
envelope: yes
genome: plus strand RNA (10-11 kbp)
example: ______
species: humans, mosquitos, monkeys
tissue: skin, epithelia, CNS of fetus
disease: fever, rash, birth defects,
Guillain–Barré syndrome

A

zika; flaviviruses

219
Q

structure: polyhedral virion
envelope: yes
genome: plus strand RNA (26-32 kbp)
example: _____
species: human, mammals
tissue: lungs, gastrointestinal tract
disease: ________

A

SARS; SARS; coronavirus

220
Q

structure: very small, polyhedral virion
envelope: no
genome: plus strand RNA (7.5 kbp)
example: __________
species: human
tissue: intestine, spinal cord
disease: paralysis

A

poliovirus; picornavirus

221
Q

structure: small, polyhedral virion
envelope: no
genome: plus strand RNA (7.3-8.3 kbp)
example: _________
species: human
tissue: intestine
disease: gastroenteritis

A

norovirus (calciviruses)

222
Q

structure: helical virion
envelope: yes
genome: minus strand RNA (11 kbp)
example: _______
species: human, mammals
tissue: CNS
disease: neurological disease

A

rabies; rhabdovirus

223
Q

structure: helical virion
envelope: yes
genome: minus strand RNA (18-19 kbp)
example: ________
species: human, mammals
tissue: broad: fibroblasts, dendritic cells, endothelium,
epithelium
disease: ______________

A

ebola; ebola hemorrhagic fever; filovirus

224
Q

structure: helical virion
envelope: yes
genome: minus strand RNA (15-19 kbp)
example: _________
species: human
tissue: respiratory tract, immune system, skin
disease: rash, respiratory illness

A

measles; paramyxovirus

225
Q

structure: helical virion
envelope: yes
genome: minus strand RNA, 6-8 segments
example: _________ virus
species: human
tissue: respiratory epithelia
disease: __________, respiratory diseaes

A

influenza; influenza; orthomyxoviruses

226
Q

structure: helical virion
envelope: yes
genome: minus strand RNA, segmented
example: __________
species: human, rodents
tissue: broad: blood vessels, kidneys
disease: hemorrhagic fever, renal and pulmonary
syndromes

A

hantavirus; bunyaviruses

227
Q

structure: helical virion
envelope: yes
genome: minus strand RNA, segmented
example: _____________
species: human, rodents
tissue: vascular endothelial cells, dendritic cells
disease: acute viral hemorrhagic fever

A

lassa fever virus; arenaviruses

228
Q

structure: polyhedral virion
envelope: yes
genome: plus strand RNA* (7-12 kb)
example: ______
species: human
tissue: T-cells, immune system cells
disease: _______

A

HIV; AIDS; retroviruses

229
Q

structure: small, polyhedral virion
envelope: yes
genome: double-stranded DNA*, linear (1.7-2 kbp)
example: __________
species: human
tissue: liver
disease: cancer

A

hep B; hepadnaviruses

230
Q

structure: no virion
envelope: —
genome: minus strand RNA, circle
example: __________
host: human
tissue: liver
disease: ?

A

hep delta

231
Q

Zika viruses are spread by what species?

A

mosquitoes

Microbiology (15 decks)

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