Intro to Medical Microbiology Flashcards
(104 cards)
1
Q
In regards to host response evasion strategies, give an example of the “elicit minimal host response”
A
Herpes simplex virus remains latent in host cells for long periods without causing pathology
2
Q
In regards to host response evasion strategies, give an example of the “evade effects of host response”
A
mycobacteria survive within a granuloma created to localize and destroy infection
3
Q
In regards to host response evasion strategies, give an example of the “depress host response”
A
HIV destroys T cells; Malaria depresses immune response
4
Q
Viruses, spirochetes, and trypanosmones change surface antigens to avoid recognition by host. What is the name of this strategy?
A
antigenic change
5
Q
Viruses, bacteria, and protozoa produce acute infections faster than the immune response can develop. What is the name of this strategy?
A
rapid replication
6
Q
Genetic heterogeneity among hosts always provides some individuals with greater susceptibility or reduced immune status. This allows survival in what type of individuals?
A
weakly responsive individuals
7
Q
These are glycoproteins produced by many cells; especially leukocytes
A
interferons
8
Q
IFN-_ and IFN-_ both inhibit viral protein synthesis and activate leukocytes to kill viruses
A
IFN alpha; IFN beta
9
Q
IFN gamma signals for what?
A
upregulation of MHC I and II expression and antigen presentation; activates NK and Tc cells to kill virus-infected host cells
10
Q
Interferons are cell-specific in their production and effects, but virus non-specific. True or false?
A
True
11
Q
Interferons are induced by the presence of _-__
A
ds-RNA
12
Q
Once initiated, interferon continues for several ___
A
hours
13
Q
Interferon is produced in ___ and then ___, thus it doesn’t affect the producing cells
A
vesicles; excreted
14
Q
Interferon inhibits what?
A
translation of viral mRNA and viral replication
15
Q
Interferon production induces the common features of viral infection. What are these symptoms?
A
flu-like: fever, myalgia, headache
16
Q
Who discovered microorganisms using the microscope?
A
Van Leeuwenhoek (1674)
17
Q
Who used Linnaen method to organize bacteria: Genus species
A
Muller (1774)
18
Q
Who discovered anthrax, rabies, plague, cholera, and TB
A
Koch and Pasteur (1870’s)
19
Q
who created the first antibacterial, Salvarsan (for syphilis)?
A
Ehrlich (1910)
20
Q
Who discovered penicillin?
A
Fleming (1928)
21
Q
Who discovered sulfanilamide?
A
Domagk (1935)
22
Q
Who discovered streptomycin?
A
Waksman (1943)
23
Q
Who was the first to cultivate viruses using cell culture?
A
Enders (1946)
24
Q
What microbes can you visualize under a light microscope?
A
protozoa and bacteria (10^-6)
25
What microbes can you visualize with an electron microscope?
viruses (10^-8)
26
These are deviant and disruptive proteins. Associated with Mad Cow Disease
prions
27
These are obligate intracellular parasites or lack cell well; cause cell and tissue destruction. Ex: chlamydia, mycoplasma, Rickettsia
degenerate bacteria
28
These microbes are free-living, possess and cell wall. The prokaryotic type lacks a nuclear membrane, ER, and mitochondria
bacteria
29
These microbes can be simple or complex. They are eukaryotic, contain an ER, mitochondria, and golgi; can be unicellular or multicellular; and utilize asexual reproduction
fungi
30
These microbes are eukaryotic; complex, unicellular or multicellular.
Ex: cryptosporidium, tapeworm
parasites
31
These microbes are ectoparasites
| ex: mites, fleas, lice, sarcoptes scabiei
arthropods
32
Spores, prions, and mycobacteria are examples of what type of organism?
resistant
33
This type of sterilization utilizes boiling (killing vegetative cells) or the use of an autoclave (killing spores in 15 min or more)
moist heat
34
This type of sterilization utilizes an over for 2-3 hours at 170 degrees celsius to effectively kill spores
dry heat
35
This type of sterilization utilizes HEPA filters and removes microorganisms
filtration
36
This type of sterilization utilizes germicidal UV, ionizing gamma, and produces DNA damage
radiation
37
This type of sterilization utilizes toxic alkylating agent used for heat-sensitive materials, however, toxic or mutagenic by products
ethylene oxide gas
38
In ____ there is total destruction of all microorganisms. In ____ there is destruction of most organisms. In ____ most organisms on skin or in tissue are killed.
sterilization; disinfection; antisepsis
39
With disinfection, spores and mycobacteria might not be killed. True or false?
true
40
Hot water, glutaraldehyde, peracetic acid, hydrogen peroxide, phenolics, alcohols, ammonium are all examples of what?
disinfectants
41
Antisepsis kills most organisms including ____, but not ____
mycobacteria; spores
42
In regards to antisepsis, this is a carrier of iodine, which precipitates/oxidizes proteins, kills most organisms, skin disinfection, residual antiseptic ability.
iodophors
43
In regards to antisepsis, this is slower killing, but has residual action, utilizes chlorine (powerful oxidant)
chlorhexidine
44
In regards to antisepsis, these compounds attack lipid membranes, kill mycobacteria, and their action is improved by halogens
phenolic compounds
45
What is the phenol coefficient?
a ratio of dilution factors used to compare an agent against phenol under constant conditions
46
Quarternary ammonioum compounds are 4 organic groups linked to nitrogen. What do they attack?
membranes
47
___ is the mixing of chromosomal elements from different strains, the mechanism of genetic shift
reassortment
48
___ is the mechanism of genetic drift (small changes)
mutation
49
What does reassortment require?
segmented genomes
50
What type of mechanism do RNA viruses: Bunyaviridae, Orthomyxoviridae, Arenaviridae, and Reoviridae utilize?
mechanism of "genetic shift" where influenza viruses rapidly acquire new hemagglutinin and neuraminidase. This is the initiating factor in many epigenetics.
51
The following functions are of what type of cells?:
Bind DNA
DNA uptake
DNA integration
competent cells
52
S. pneumoniae, S. aureus, and B. subtilis are all Gram ____
positive
53
N. meningitidis, N. gonorrhoeae, H. flu, and E. coli are all Gram _____
negative
54
Name the prokaryotic toxins (ABCDE)
```
shigA-like toxin (E. coli)
Botulinum toxin (Cl. botulinum)
Cholera toxin (V. cholerae)
Diphtheria toxin (C. dip)
Erythrogenic toxin (S. pyogenes)
```
55
Sigella flexneria is an ____
adhesin
56
Episomes, sexual pili, and homology dependent recombination are all aspects of part of prokaryote genetics?
conjugation
57
True or false? There are many Gram Positive species and few Gram negative species that participate in conjugation.
false; many Gram neg, few Gram pos
58
In regards to prokaryote genetics, this is the exchange between two chromosomes, all organisms (except most RNA viruses) utilize this. Follows: chromosomal transformation, transduction, or conjugation
recombination
59
Recombination occurs in most ___ viruses and the ___ at the DNA provirus stage
DNA; Retroviridae
60
Among RNA viruses, only the _____ show recombination
Picornaviridae
61
This can be considered "illegitimate recombination". It is the jumping of genes or transposons.
Transposition
62
Two copies of expressed genes in one cell. A functional gene will cover a deficiency caused by a mutant gene.
complementation
ex: 2 strains of virus in one cell, a plasmid carrying an active gene in a cell carrying an inactive mutant gene
63
Two viruses in one cell. Progeny viruses may combine attributes of both parental viruses.
Phenotypic mixing
ex: progeny may have nucleic acid from one virus in a nucleocapsid containing protein components from a second virus
64
These tests can be used to identify antibiotic resistant bacteria
ex: Mueller-Hinton
diffusion tests
65
These tests can determine the MIC (minimum inhibitory or bacterial concentration) useful for treatment options
Dilution tests
66
Is the following a virus or bacteria?:
filterable agents
obligate intracellular parasites
depend on host
virus
67
Viruses reproduce by ___
assembly
68
Viral genomes can be single or double stranded chromosomes. True or false?
true
69
Viral genomes are only unsegmented. True or false?
false; can be segmented or unsegmented
70
Bacteria reproduce by ____ > ____
duplication > fission
71
Bacteria genomes are only unsegmented. True or false?
true
72
The viral capsid (and envelope) is a protein coat resistant to the environment. It is made up of capsomer subunits called ____ and ____ which make up the 20 faces of the isohedral or icosadeltahedral capsid
pentamers; hexamers
73
Pentamers and hexamers are made of ____
protomers
74
Helical and complex viruses contain only ___, no ___
protomers; capsomers
75
These are glycoprotein projections through the envelope and are the viral attachment site
spikes
76
In regards to the viral propagation in the human host, what are three places of entrance?
respiratory, GI, parenteral
77
```
Give the correct order of the viral propagation cycle at the cellular level:
penetration
adsorption
replication of nucleic acid
uncoating
maturation and release
```
```
Adsorption
Penetration
Uncoating
Replication of nucleic acid
maturation and release
```
78
This is a common/highly specific process for viral cell invasion. It requires interaction between unique viral surface proteins and highly specific host cell surface receptor sites.
adsorption
79
For the following virus, give the viral attachment protein, target cell, and cell surface receptor if it has one:
adenovirus
vap: fiber protein
target cell: epithelial (muco)
80
For the following virus, give the viral attachment protein, target cell, and cell surface receptor if it has one:
EBV
vap: gp350, gp220
Target cell: B
csr: C3d, CR2
81
For the following virus, give the viral attachment protein, target cell, and cell surface receptor if it has one:
HIV
vap: gp120
target cell: helper T
csr: CD4
82
For the following virus, give the viral attachment protein, target cell, and cell surface receptor if it has one:
Influenza A
vap: hemagglutinin gp
target cell: epithelial (respiratory)
csr: sialic acid
83
For the following virus, give the viral attachment protein, target cell, and cell surface receptor if it has one:
measles
vap: heamgglutinin gp
target cell: epithelial respiratory
84
For the following virus, give the viral attachment protein, target cell, and cell surface receptor if it has one:
Rabies
vap: G protein gp
target cell: neuron
csr: Ach receptor, NCAM
85
For the following virus, give the viral attachment protein, target cell, and cell surface receptor if it has one:
Rhinovirus
vap: VP1-2-3 complex
target cell: epithelial respiratory
csr: ICAM-1
86
For the following virus, give the viral attachment protein, target cell, and cell surface receptor if it has one:
Rotavirus
vap: VP7
target cell: epithelial (columnar)
87
these viruses have membranes that fuse, releasing the nucleocapsid into the cell
enveloped viruses
88
these viruses have nucleocapsids that bind to the membrane receptor sites, then either are digested through the membrane or are engulfed and enter as a vesicle
naked viruses
89
Uncoating of the plasmid always occurs in the ___ of the host cell
cytoplasm
90
Coincident with the end of uncoating is the ___ phase (time of viral replication)
eclipse
91
DNA viruses replicate where?
in the nucleus (except poxviruses)
92
symmetrical transcription of dsDNA > dsRNA > induces ___
interferon
93
In late transcription, viral capsid proteins are made in ____ > ____
cytoplasm; nucleus
94
All RNA viruses replicate in the ____
cytoplasm (except orthomyxoviruses and retroviruses)
95
The RNA viral genome must encode what? It is absent in eukaryotic cells
RNA-dependent RNA poly
96
In regards to viral propagation by RNA viruses, the ssRNA that is released by uncoating will act as what?
dsRNA > mRNA > interferon
97
In regards to naked viruses, maturation consists of two main processes:
1. assembly of capsid
2. capsid association with nucleic acid
note: maturation occurs at site of nucleic acid replication
98
RNA viruses are usually released rapidly after maturation. True or false?
true
99
DNA viruses are usually not released rapidly. True or false?
true
note: accumulate large numbers at site of maturation forming inclusion bodies
100
How is an elevated virus released?
nucleocapsid buds out with envelope, antigenic mosaic of viral and host proteins stud the envelope, tends to be slowly/continuously released by budding
101
These viruses have 2 membranes, 1 around the nucleoid and are released by cell lysis
complex
102
Normally when a virus enters a cell, it reproduces at a rapid are and produces large numbers of progeny virus. This is called the ___ cycle
lytic
103
The basis for latency has been attributed to what?
lysogenization
lack of pathogenicity of virus
suppression of immune system
104
A latent infection is usually activated by what?
systemic shock
