Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

446- ID and transplant > Introduction to Virology > Flashcards

Introduction to Virology Flashcards

1
Q

viruses are a ____ complex that infect cells

A

nucleoprotein

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

viruses are metabolically

A

inert

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

which is false about viruses
1. DNA viruses assemble in cytoplasm
2. mostly highly species specific
3. are metabolically inert
4. virion is the whole spreadable particle

A

1- nucleus

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

what is the nucleocapsid

A

genome + capsid

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

capsomere functions

A

helps define shape of capsid

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

viral envelopes are
1. host
2. virus
3. both host and virus
4. made from capsomeres

A

1

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

Viruses with similar structural, henomic, and replication properties are grouped into __________ (ex- suffix_________)

A

families
-viridae

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

families are sudivided into ____

A

genera

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

virus subtypes are based on

A

nucleotide sequence and antigenic reactivities

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

viral capsid forms include

A

helical
icosahedral
complex

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

basic viral envelope forms include

A

icosahedral nonenveloped
icosahedral enveloped

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

the viral envelope is involved in (4)

A

attachment, entry, assembly, release

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

envelope proteins are ___, lipids are ______

A

viral
host

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

T or F: if membrane envelope is destroyed, the virus infects all cells in its proximity by direct benetration

A

F- virus becomes noninfectious

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

3 forms of adsorption/ attachment

A

direct penetration
fusion
endocytosis

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

describe direct penetration with viral attachment

A

Usually nonenveloped virus penetrating host cell through receptors on side of plasma membrane = release virus directly into host cell
Capsid is left behind

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

describe fusion with viral attachment

A

only with enveloped viruses. Viral glycoproteins bind receptors of host cell = fuse envelope with membrane and releases viral capsid inside host cell

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

describe endocytosis with viral attachment

A

Host cell engulfs virus, capsid, and envelope all together- host cell mem, envelope, and capsid all disintegrate inside host cell

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

describe uncoating

A

removing all or part of viral capsid
viral genome is accessible to host cell’s transcription and translation machinery

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

DNA viruses replicate in

A

host cell nucleus mediated by viral enzymes

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

T or F: viruses come with some of their own enzymes to reproduce within host cell

A

T

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

T or F: all portions of DNA virus are replicated in host cell cytoplasm

A

F- only DNA in nucleus, rest are in cytoplasm

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

which virus is the exception to the DNA virus replication rule

A

poxvirus- DNA but synthesize in cytoplasm

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

____ type RNA acts as mRNA

A

+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

viral proteins with RNA viruses are made in

A

cytoplasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

T or F: naked RNA nucleic acid is infectious

A

T

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

neg sense RNA must first ___________________ before it can replicate

A

make a + sense RNA/ mRNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

viral capsomers _______ assemble into crystal like arrays

A

self

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

describe the 3 points of viral assembly

A

Replication of viral genome and synthesis of proteins are complete
Viral capsomers self assemble into crystal like arrays
Newly formed capsid is filled with viral nucleic acid and buds out

30
Q

enveloped viruses are typically released by

A

budding

31
Q

is budding always lethal to the host cell?

A

not always, sometimes

32
Q

how are nonenveloped virions released

A

when the cell lysis

33
Q

After encountering a host cell, the virus must (3)

A

Enter the cells
Undergo a period of primary replication
Spread to its final target tissue- infect and successfully replicate in a susceptible population of host cells

34
Q

3 types of viral infections

A

lytic
latent
chronic

35
Q

describe a lytic infection

A

Multiple rounds of replication results in death of the host cell (virus factory)
Polio, influenza

36
Q

describe a latent infection

A

No immediate production of progeny virus
Viral nucleic acid carried as extrachromosomal element or an integrated sequence in the host cell DNA

37
Q

in latent infections, the viral nucleic acid is carried as an ___________ or __________

A

extrachromosomal element
integrated sequence in host cell DNA

38
Q

describe a chronic viral infection

A

Virus particles continue to shed after the period of acute illness has passed
slow release of virus particles without death of host cell

39
Q

4 types of virus host cell interaction

A

lytic
cell transformation
latent/ occult
cell fusion to form multinucleated cells

40
Q

respiratory route of transmission involves

A

Aerosol droplets, nasal secretions, or saliva via coughing or sneezing

41
Q

common cold is spread by

A

aerosols and fomites

42
Q

GI route of viral infection is from

A

viral shed in feces- contaminate food or water - ingested by susceptible individual
stool tainted hands, poor hygeine

43
Q

transcutaneous route of infection involves

A

Direct inoculation via insect, animal bites or mech devices like needles

44
Q

west nile is spread

A

transcutaneously

45
Q

why are humans a dead end for west nile

A

do not develop high levels of virus in bloodstream = can’t pass virus on to other biting mosquitos

46
Q

iatrogenic transcutaneous infections are induced by

A

medical or diagnostic procedures- contaminated blood products, infected donor material, purposeful as vaccination, etc

47
Q

sexual transmission of viruses may see the virus spread to

A

to other parts of the body or remain near the site of entry

48
Q

horizontal sexual transmission is between

A

between members of a susceptible host population

49
Q

vertical sexual transmission is

A

infection of fetus in utero through virus carried in germ line or infecting the placenta or in the birth canal

50
Q

T or F: viruses may stay at the same site or spread to other area to produce disease

A

T

51
Q

which has no role in primary response or acute viral infections
1. complement
2. cell mediated immunity
3. antibody response
4. 3+4

A

3

52
Q

antibody response is very important in ______________. neutralizing antibodies reduce effectiveness by _________, _____, _______

A

preventing reinfections
inhibiting attachment, penetration, or uncoating of virus

53
Q

viruses can trigger the activation of the ___ and _______ pathways of complement

A

alternate
classic

54
Q

virus activated complement enhances _________ = _____________

A

phagocytosis of viruses = lysis of enveloped virus or virus infected cells

55
Q

what happens in cell mediated immunity

A

infected cells are susceptible to the action of lymphocytes that recognize viral antigens on their surface = can be lysed

56
Q

CPE applies to

A

virus induced cellular changes that are visible by light microscope

57
Q

the most effective way to visualize viral changes to cells is by

A

staining cells with chromatic dyes

58
Q

what is the basic and acidic dye in CPE

A

basic = hematoxylin
acidic = eosin

59
Q

direct detection fluorescent antigen is used for

A

viruses that create lesions

60
Q

how to prep sample for direct fluorescent antigen observation under UV microscope

A

Vigorous scraping of lesion base is essential- remove scab before sampling

61
Q

dierct detection fluorescent antigen uses _______________________ for detection

A

Uses HSV antigen specific murine MAbs (fluorescein labeled) for detection

62
Q

Direct detection fluorescent antigen is observed under

A

UV microscope

63
Q

pros of viral culture

A

Can differentiate between viable and non-viable viral particles
Able to detect unknown viral etiologies
Inexpensive compared to PCR

64
Q

cons of viral culture

A

Relatively slow
Does not support growth for all types of viruses
Toxins can resemble cytopathic effects = false +
Contamination due to bacteria, fungus and mycoplasma reduce the sensitivity of viral detection
Endogenous virus from cells can be mistaken as the infectious agent

65
Q

_________: fourfold or greater increase in antibody titre to spec viral agent in acute and convalescent sera (3-4wks later)

A

serology

66
Q

IgM antibody is a marker of

A

current/ acute rxn

67
Q

IgG is a marker of

A

past infection in the last 3-4weeks

68
Q

molecular studies are the

A

detection of even single copies of virus genome in tissues or cells from body fluids

69
Q

molecular studies utilize _____ which may be visualized by ____ or _________

A

PCR
gel electrophoresis
real time by computer

70
Q

pros of viral amplification

A

Can detect v low number of viruses
Rapid
High throughput
Multiplexed assays

71
Q

cons of viral replication

A

Contamination due to high conc of amplicons
Detection of dead organisms
False + and false - results
Expensive
Special training

446- ID and transplant (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions