Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Virology > Lab2 > Flashcards

Lab2 Flashcards

(83 cards)

Start Studying
1
Q

Viruses that have surface proteins (haemagglutinins)?

A

Orthomyxoviridae, Paramyxoviridae, Coronaciridae, Parvoviridae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what makes lattice formation at the bottom of the tube?

A

The sedimentation of the virus-joined red blood cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What can be demonstrated with haemagglutination test?

A

The method is not sensitive, so it is not perfect method to demonstrate the presence of low number of virions, but because of its simplicity it provides a very convenient assay if high concentration of virions are available

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The haemagglutination titre is?

A

The end (highest) dilution of a virus suspension, where the haemagglutination still appears

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the red blood cell suspension used for haemagglutination titre?

A

0.5-1% washed erythrocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is haemagglutinins?

A

Surface proteins able to bind to erythrocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is haemagglutination?

A

lattice-formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is used in haemagglutination inhibition tests?

A

HA unit of viruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

CPEs are alterations in the morphology of cells due to?

A

virus infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

CPE is mainly observed in?

A

cell cultures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

CPE is usually a result of?

A

degenerative processes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

ex of: toxic effect of adsorption?

A

Adenoviruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

ex of: Virus proteins inhibit cellular translation?

A

Herpes-, pox-, togaviruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

example of: Early proteins inhibit cellular nucleic acid transcription and replication?

A

herpes-, adenoviruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

ex of: Viral proteins damage the cytoplasmic membrane permability - osmotic change

A

herpesviruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

ex of: cytoskeleton depolimerization

A

herpes, paramyxoviruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

ex of: expression of fusion proteins

A

herpes, paramyxoviruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Inclusion bodies appear at?

A

the site of assembly of nucleocapsid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Inclusion bodies are?

A

virus depositions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How can inclusion bodies be observed?

A

In stained cells (of cell cultures or organ sections):
- they have homogenous staining, surrounded by a narrow light stripe, the so called “halo” due to shrinkage after fixation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What causes the “halo”?

A

Shrinking after fixation. of stained inclusion bodies.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Intranuclear inclusion bodies is caused by?

A

DNA and sometimes RNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Intranuclear inclusion bodies caused by DNA viruses?

A

Replicating in the nucleus.

Parvo-, papilloma-, polyoma-, adeno-, herpesviruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Intranuclear inclusion bodies caused by RNA viruses?

A

Orthomyxo-, paramyxo-, arteri-, bornaviruses.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Cowdry-A, Cowdry-B types depends on?
the state of the synthesis of macromolecules.
26
How can Intranuclear inclusion bodies be stained?
``` Basophil = parvo Amphophil = adeno Eosinophil = herpes ```
27
When can caryomegalia and/or perichromasia be observed?
in case of high nuber of inclusion bodies or large inclusion bodies in the nucleus
28
Intracytoplasmic inclusion bodies caused by?
RNA viruses, sometimes DNA (if the viruses replicate in the cytoplasm )
29
What can be de DNA viruses replicating in the cytoplasm of Intracytoplasmic inclusion bodies?
Poxviruses, ASFV
30
How can Intracytoplasmic inclusion bodies be stained?
Eosinophil or rarely basophil (poxviruses) particles.
31
What are the Negri bodies and the Guarnieri bodies?
Pathognomic inclusion bodies of Intracytoplasmic inclusion bodies. - Negri bodies: neuron cells, rabies - Guarnieri bodies: epithelial cells, small pox
32
What is the reason for Cell rounding?
Cytoskeleton depolymerisation and a loss of electrolytes.
33
What is observed if the cell rounding is UNstained?
Double refraction, detachment and shrinkage
34
What is Syncytium-formation caused by?
enveloped viruses.
35
What are the enveloped viruses causing Syncytium formation?
Alphaherpes-, paramyxo-, pneumo-, coronaviruses
36
Where are the fusion proteins (of the Syncytium-formation) found?
On the surface of the virus and on the cytoplasmic membrane of the cell
37
What are the fusion proteins on the surface of the virus used for?
Viral penetration.
38
What are the fusion proteins on the cytoplasmic membrane used for?
cause fusion of the neighboruing cell´s membranes, infected and non-infected
39
What happens when membrane tunnels are formed between the cells? (in consequence of the fusion proteins?
makes the intracellular spread of viruses possible
40
What are polykaryocytes and/or syncytia?
Giant cells with many nuclei, which is formed because of the fusion of the cells (syncytium formation)
41
Lumpy cell nucleus is the consequence of?
chromatin conglomeration, rearrangement or changed refraction (caused by parvovirus).
42
The lumpy disintegration of the nucleus is characteristic for?
EHV-1 (horse herpesvirus type1) in the liver of foals and African Swine Fever Virus (ASFV) in lymphatic system
43
Where can the vacuoles appear? | Cell vacuolisation
- in the nucleus (i.e by adenovirus infection) | - in the cytoplasm (i.e by flavi-, herpes- and retrovirus infections)
44
Cytolysis occurs bacause of?
the damage of the cell membrane or caused by lysosomal enzymes.
45
The cell can also explode when? | cytolysis
when the virions are released, in case of certain enteroviruses.
46
The viral protein called haemagglutinin incorporates into the? (haemadsorption)
Cytoplasmic membrane of the infected cell
47
What happens when the viral protein (haemagglutinin) incorporates into the cytoplasmic membrane of the infected cell?
It is able to adsorb erythrocytes on the surface of the monolayer
48
Where does the haemagglutinin adsorb the erythrocytes?
on the surface of the monolayer
49
Haemadsorption has diagnostic value in case of?
- Paramyxoviruses (haemadsorption +, haemagglutniation -) | - ASFV (haemadsorption +, haemagglutination -)
50
The occurance of the CPEs in a cell culture can be?
diffuse, all around the cell culture or in some cases local/focal?
51
What is the CPE called when its Local/focal?
Plaque
52
More plaques are generally formed in?
lower virus concentrations (multiplicity of infection, MOI)
53
Medium used to supplement the plaque formation?
Agar, carboxymethyl cellulose or metrizamide
54
What is the result of using medium with agar, carboxymethyl cellulse or metrizamide?
It results in semisolid maintance fluid that retart the free movement of the virus in the cell culturing dish, therefore the viruses are forced to spread from cells to neighboruing cells.
55
Plaque formation is usefull in case of?
virus purification, when subsequent passages of viruses taken from singular plaques are propagated.
56
When is establishment of virus strains possible?
virus purification, when subsequent passages of viruses taken from singular plaques are propagated.
57
When is plaque counting used to determine the quantity of virus particles or antibody content of the sample?
In virus quantification and plaque reduction neutralisation tests (serological investigation)
58
Does all virus infections result in CPE?
No, and it is not always connected to the pathogenicity.
59
Ex of what can cause CPE?
Spumaviruses, but they are orphan
60
The cytophatic character of a virus strain man change due to?
mutations (i.e Bovine viral diarrhea virus- BVDV)
61
How can you investigte non-cytopathogenic viruses in cell culture?
the propagation of the virus in cell culture should be supplemented by IPA or IF.
62
the viral antigens are expressed on?
the surface of the cell
63
using IF test, the infected cells appear?
with yellowish-green spots indicating the prescence of ciral genes
64
Ex of investigation of non-cytopathic viruses with Electronmicroscopic-investigation?
Rabbit haemorrhagic disease (RHD)
65
Ex of investigation of non-cytopathic viruses with Immuno-electronmicroscopic (IEM) investigation?
rotaviruses, parvoviruses in faeces sample
66
Ex of investigation of non-cytopathic viruses with Complement-fixation test?
Foot and mouth disease
67
Ex of investigation of non-cytopathic viruses with Agar gel-precipitation (AGP) and Agar Gel Immune diffusion (AGID)?
equine infectious anaemia
68
Ex of investigation of non-cytopathic viruses with Counter current immunoelectrophoresis (ccIEF)?
parvo-, rota-, coronaviruses
69
Name the test that can be used for investigation of non-cytopathic viruses:
- artificial infection - electronmicroscopic investigation (EM) - immuno-electroscopic investigation (IEM) - complement-fixation test - Agar-gel-precipitation (AGP) - Agar gel immune diffusion (AGID) - Counter current immunoelectrophoresis (ccIEF) - ELISA (enzyme linked immunosorbent assay) - RIA (radio-immuno assay) - Haemagglutination (HA) - detection of viral nucleic acid by polymerase chain reaction
70
what can be seen by identification of viruses with microscopic investigation:
CPE, tissue specificity, type of pocks, haemadsorption
71
what can be seen by identification of viruses with electronmicroscope EM?
the dimension, size, shape of the virion, its symmetry, surface etc.
72
Identification of viruses by Physico-chemical investigation of vegative viruses:
- enveloped/non-enveloped virus - DNA/RNA virus - Single/double stranded nucleic acids
73
If the virus loses its infectivity after chloroform treatment?
then it is an enveloped virus
74
What is added to the growth media in DNA/RNA viruses? | Physico-chemical investigation of vegative viruses:
halogenated deoxy-uridine
75
What does the halogenated deoxy-uridine do in the DNA?
it incorporated into the DNA in place of deoxy-thymidine and this way inhibits the DNA replication, but does not influence RNA replication
76
How does the halogenated deoxy-uridine inhibit the DNA replication?
it incorporates into the DNA in place of deoxy-thymidine
77
What happens after acridin-orange staining?
the single strand shows reddish-orange flourescense, and the double strand shows greenish-yellow.
78
Hos is the nucleus in the dsNA with acridin-orange stained?
green
79
Hos is the cytoplasm in the ssNA with acridin-orange stained?
orange
80
What can you use to investigate group-specific antigens?
AGP, IPA, IF, IEM, ccIEF, ELISA, RIA, HA
81
How can you determine the serotype?
Virus neutralisation test and/or haemagglutination-inhibition test
82
How can you determine subtype, variant?
- clinical signs - investigation of nucleic acid (heteroduplex techniwues, hybridization, sequencing) - investigation with monoclonal antibodies
83
How can you investigate nucleid acids?
heteroduplex techniques, hybridization, sequencing.

Virology (25 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions