Micro 2 test 2 Flashcards
(124 cards)
1
Q
Acellular
A
they are not a cell
2
Q
Size Range
A
200-300 nanometers (variola)
18-30 nanometers (polio and rhinoviruses)
3
Q
morphology
A
helical (rod); cubic (geometric)
4
Q
No combination
A
RNA and DNA
5
Q
Surrounded by a
A
capsid
6
Q
what are capsids made of
A
capsomeres
7
Q
What do viruses require for replication?
A
a living cell
8
Q
If a virus reproduces without killing a cell it is
A
a persistant infection
9
Q
If a virus kills a cell it is
A
lytic
10
Q
Viruses show specificity how?
A
by species e.g. polio->primates but not chicken
11
Q
What is tropism?
A
affinity for target tissue
12
Q
What are interferons?
A
a family of eukaryotic cell protiens made and released by host cells in response to the presence of viruses
13
Q
What do interferons allow?
A
communication between cells to trigger protective defenses
14
Q
What is the least favored method for cultivating viruses?
A
Animals (because they may have other viruses)
15
Q
infection and replication
5 categories
A
attachment penetration uncoating biochemical replication assembly and maturation
16
Q
attachment happens because of
A
ionic bonds and receptors
17
Q
penetration happens because of
A
membrane fusion
18
Q
uncoating happens where
A
intracellular
19
Q
assembly and maturation happens where?
A
in nucleus and cytoplasm (DNA) cytoplasm only (RNA)
20
Q
How do you harvest viruses?
2 ways
A
- Harvest from liquid growth medium which overlays cell culture
- differential centrifugation (used for purity)
21
Q
What are the assays? (6)
A
- electron microscope
- titration
- plaque assay
- lethal dose 50% (LD-50)
- Hemagglutination (HA)
- ELISA (enzyme-linked immunosorbant assay)
22
Q
What is electron microscope used for?
A
observe/examine the size structure of various viruses
23
Q
what is titration used for?
A
to determine titer of the virus in the sample
24
Q
What is plaque assay used for?
A
to quantitate viable virus particles derived from both bacteria and animals
25
What do plaques on a lawn of a cell represent?
a virus infection
26
Each plaque represents
one virus particle
27
What is plaque assay analogous to?
viable cell count in bacteriology
28
virus induced plaques serve as a tool for _______
enumeration
29
LD-50 assay measures what?
the highest dilution of a virus that is required to kill 50% of the experimental animals
30
What does LD-50 not give?
a specific virus particle number
31
What does LD-50 provide?
an idea of the relative strength of the preparation (when comparing two or more samples)
32
Hemagglutination does what?
provides a means of detecting the viruses prescence and quantitating their numbers by (causing RBC clumping)
33
ELISA uses what to test?
blood serum (antibodies)
34
ELISA is ________ and _______ based.
colored and enzyme
35
ELISA is particularly useful for
HIV testing
36
HIV testing relies on what two assays?
1. ELISA (introductory)
| 2. Western Blot (confirmatory)
37
What assay requires a serial dilution of the virus preparation?
hemagglutination
38
Which assay requires incubation of the virus preparation?
hemagglutination
39
What are the steps of lytic infection?
1. infection
2. infected
3. bacteriophage maturation
4. bacteriophage maturation
5. lysis
40
What step of lysogeny has induction?
3---->4 (e.g. temperature)
41
What step of lysogeny has transduction?
4
42
What step of lysogeny has lysis?
5
43
Are RNA viruses permanent?
no
44
T or F
| RNA viruses integrate into cells.
F
45
T or F
| RNA viruses replicate in the nucleus.
F
46
T or F
| RNA viruses are single stranded.
T
47
What are the 6 common RNA virus families?
1. PICORNAVIRIDAE
2. RETROVIRIDAE
3. TOGAVIRADAE
4. RHABDOVIRIDAE
5. PARAMYXOVIRIDAE
6. ORTHOMYXOVIRIDAE
48
What are some examples of picornaviridae?
polio, ECHO, Coxackie, HAV, Rhino (common cold)
49
What are some examples of retroviridae?
animal tumor and leukemia, HIV, HTLV-1 & HTLV-2
50
What are some examples of Togaviridae?
encephalitis
51
What are some examples of Rhabdoviridae?
rabies
52
What are some examples of Paramyxoviridae?
parainfluenza, mumps, measles, respiratory syncytial
53
What are some examples of orthomyxoviridae?
influenza
54
T or F
| DNA viruses are single stranded.
F
55
T or F
| DNA viruses are permanent.
T
56
T or F
| DNA viruses do not integrate into cells.
F
57
What are 4 common DNA virus families?
1. Adenoviridae
2. Herpetoviridae
3. Poxviridae
4. Papovaviridae
58
What are examples of adenoviridae?
human serotypes of adeno viruses
59
What are examples of Herpetoviradae?
herpes simplex viruses, Varicella-zoster virus, cytomegalo virus, epstein-barr virus
60
What are some examples of poxviridae?
smallpox, vaccina
61
What are examples of papovaviridae?
HPV (human papilloma virus)
62
What RNA virus is not single stranded?
Reviovirus (dsRNA)
63
Where do RNA viruses replicate?
cytoplasm (except retrovirus)
64
SS(-)RNA carry what?
RNA-dependent RNA polymerase
65
A virion-associated polymerase is also carried by what?
Reovirus, Retrovirus (reverse transcriptase)
66
What family does Norwalk virus belong?
Calciviridae
67
T or F
| Calciviridae is a naked virus
T
68
What is the most common cause of viral diarrhea in adults?
Norwalk virus
69
What is the #1 cause of infectious diarrhea and major cause of infant mortality worldwide?
Rotavirus
70
What other virus belongs to the Caliciviridae other than norwalk virus?
Hepatitis E
71
T or F
| The picornaviridae family is enveloped.
F
72
What members of the Picornaviridae family are enteroviruses?
1. Polio
2. ECHO
3. Coxakie A & B
4. Hepatitis A
73
What cells does polio attack?
1. Peyer's patches of intestine
| 2. Motor neurons (encephalic)
74
Is man the only host of polio?
yes
75
Is paralysis a usual occurence in polio
can happen but not usual
76
Where does polio spread?
upper and lower alimentary tract
77
Does polio attack various areas of the brain and spinal cord?
yes
78
What is the dead vaccine for polio?
SALK
79
What is the live vaccine for polio?
SABIN
80
Which vaccine for polio has no risk?
SALK
81
Which vaccine for polio has a oral intake and gives permanent immunity>?
SABIN
82
T or F
| Polio is neurotropic.
T
83
What does ECHO stand for?
Enteric Cytopathic Human Orphan virus
84
What are some examples of ECHO serotypes?
1. Aseptic meningitis
2. paralysis
3. gastroenteritis
4. colds etc.
85
Is man the only host of the ECHO virus?
yes
86
Is the ECHO virus usually serious?
no
87
Where is the Coxackie virus from?
Coxackie, NY
88
What family does Coxackie virus belong?
Picornaviridae
89
Coxackie A & B share what?
1. both can cause aseptic meningitis
| 2. man is the only host
90
Coxackie A is what?
Herpangina (stomatitus)
91
Coxackie A causes what?
rashes
| exanthema of extremities
92
Coxackie B is a ?
severe systemic illness of newborn (acute respiratory dxs----usually in children
93
Hepatitis A belongs to what family?
Picornaviridae
94
What is the non-enterovirus of the picornaviridae family?
Rhino virus
95
The rhino virus is AKA
coryza or cold virus
96
What is the rhino virus most commonly responsible for?
mild upper respiratory infection
97
How many serotypes of rhinovirus are known?
over 135
98
What are serotypes AKA?
immunotypes
99
Is man the only host of rhinovirus
Yes
100
What does retroviridae family include?
1. HIV
| 2. HTLV
101
What is HTLV?
Adult T-cell leukemia
102
What does HIV have an affinity for?
1. T4 cells
2. CD4 receptors
3. microphage (CCR5 chemokin receptor)
103
Can HIV infect the CNS?
yes
104
Is HIV permanent?
yes
105
Is HIV usually the cause of death?
no (secondary infection)
106
What do HIV patients usually die from>?
PNEUMOCYSTIS CARINII
| (innocuous protozoan)
107
What viruses belong to Flaviviridae?
1. Yellow Fever Virus
2. St. Louis encephalitis virus
3. Dengue virus
4. Hepatitis C virus
108
What is an AKA of yellow fever?
black jack
109
What is yellow fever virus?
hepatitis with jaundice, fever, backache, nausea, vomiting
110
Who discovered yellow fever virus?
Walter Reed
111
T or F
| Yellow Fever virus is an Arbovirus.
T
112
T or F
| Rubella is an Arbovirus.
F
113
What is the vector for the St. Louis encephalitis virus?
mosquito
114
IS the St. Louis encephalitis virus an Arbovirus?
yes
115
What kind of virus is the dengue virus?
hemorrhagic
116
T or F
| The Dengue virus only exists in tundra regions.
F (tropical)
117
Does the Dengue virus exist in america?
yes
118
What does Dengue cause?
"breakwater fever", intense backache, muscle and joint pain, rash, mental depression
119
How long does dengue last?
10 days
120
What is the vector for Dengue?
mosquito
121
T or F
| Dengue is an Arbovirus?
T
122
What belongs to the Togaviridae family?
1. WEE
2. EEE
3. VEE
4. Rubella
123
All the members of the Togavirdae share what vector?
mosquito (Arbovirus)
124
What is the reservoir for the Togaviridae?
wild birds
