Microbiology Flashcards
1
Q
The most useful microbiological staining techniques which separates bacterial organisms into two groups based on their cell wall structures
A
Gram stain
2
Q
Stains blue
A
gram +
3
Q
Stains red
A
Gram -
4
Q
Gram + cell wall structure
A
Thick 2 layers No porin channel No periplasmic space Susceptible to breakdown by penicillins and lysozyme No endotoxin
5
Q
Gram - cell wall structure
A
Thin 3 layers porin channel periplasmic space not susceptible to breakdown by penicillins and lysozyme Endotoxin (outer membrane)
6
Q
Acid fast technique is used for
A
mycobacterium tuberculosis (TB)
7
Q
Syphilis (treponema pallidum) and lyme disease ( Borrelia burgdorferi) are caused by what type of bacteria
A
Spirochetes
8
Q
These spirochetes are associated with NUP and NUG
A
Treponema denticola
9
Q
Spirochetes require this to identify them
A
dark field microscopy
10
Q
Spherical organisms
A
Coccus (cocci)
11
Q
Rod like structures
A
bacillus (bacilli) sometimes referred to as rods
12
Q
lacking distinct shape
A
pleiomorphic
13
Q
spiral shaped bacteria
A
spirochete
14
Q
The most commonly used source of energy and carbon for humans and bacteria is
A
glucose
15
Q
What are the 3 enzymes bacteria posses to break down oxygen products
A
catalase
peroxidase
superoxide dismutase
16
Q
Catalase
A
breaks down hydrogen peroxide
17
Q
Peroxidase
A
breaks down hydrogen peroxide
18
Q
Superoxide dismutase
A
breaks down superoxide radical
19
Q
what are the bacterial categories
A
obligate aerobes
facultative anaerobes
microaerophilic
obligate anaerobes
20
Q
Uses the krebs cycle and glycolysis
Must have oxygen to survive
A
Obligate aerobes
21
Q
Facultative anaerobes
A
Aerobic
Use oxygen
CAN grow in the abscence of oxygen by using fermentation
MOST DISEASE CAUSING ORGANISMS*
22
Q
Microaerophilic bacteria
A
Aerotolerant anaerobes
uses fermentation
can tolerate low amounts of oxygen because they superoxide dismutase
23
Q
Cannot tolerate oxygen
Can live in periodontal pockets and sulcus *
A
obligate anarobes
24
Q
Lag phase
A
Growth is SLOW as first
Cellular metabolic activity was NOT increased `
25
Logarithimic (exponential) phase
Growth occurs very rapidly
| Phase that microorganisms are most prone to breakdown by antimicrobial agents
26
Stationary phase
No net increase or decrease in cell numbers as nutrients are used up and waste products build up
27
After the stationary phase ends, microbes die off
death phase
28
How are gram + streptococcus arranged
chains or pairs
29
Streptococcus
microaerophilic
non-mobile
All organisms are catalase negative
30
What are the 3 groups of streptococcus
Beta hemolytic streptococcus
alpha hemolytic streptococcus
gamma hemolytic streptococcus
31
Completely lyse a RBCs
beta hemolytic streptococcus
32
partially lyse RBCs
alpha hemolytic streptococcus
33
Gamma hemolytic streptococcus
unable to lyse RBCs
34
How are beta hemolytic streptococcus arranged
in groups A-U known as lancefield groups
35
Group A streptococcus (GAS) or Streptococcus pyogenes
facultative, gram + cocci
grows in chains
highly communicable and primarily spread through person-to-person contact
36
Causes pharyngitis (strep throat), tonsillitis, scarlet fever, and cellulitis
Group A streptococcus or streptococcus pyogenes
37
Organism produces greenish tint when cultured
Viridans group of streptococcus
38
Normal inhabitants of the nasopharynx and gingival crevices
Viridans group of streptococcus
39
Viridans group of streptococcus causes 3 main types of infections
```
dental infections (caries)
endocarditis
abscesses
```
40
Causative for the majority of endocarditis cases
Streptococcus mitis
41
Streptococcus mutans
Viridans
Causative for dental caries
Ability to synthesize glucans from sucrose
Aciduric and acid producing
42
Group A streptococcus (GAS)
| Causative for pharyngitis (strep throat) and scarlet and rheumatic fever
Streptococcus pyogenes
43
Streptococcus sobrinus
Viridans
| Associated with dental caries
44
Streptococcus mitis
Viridans
| Implicated in bacterial endocarditis
45
Streptococcus sanguinis
Viridans
early plaque colonizer
implicated in bacterial endocarditis and dental caries
46
Principal commensal bacterium of the oral cavity
one of the first microbes to colonize an infants mouth
associated with the tongue*
Streptococcus salivarius
47
Causative for pneumonia
| Can be encapsulated with a polysaccharide layer makes it very resistant
Streptococcus pneumoniae
48
Generally harmless component of normal flora
| Has powerful arsenal of enzymatic and exotoxin weapons
staphylococcus
49
Important characteristics of staphylococcus
Spherical gram + cocci arranged in grapelike clusters
Facultative anaerobe
Typical lesion of a staphlycoccus is abscess formation
50
Major producer of proteins called leukocidins (destroy phagocytes); destroyed phagocytes make up much of the material of pus
Staphlycoccus aureus
51
What is the most resistant disease causing organism and the treatment
MRSA (staphylococcus aureus)
| TX; vancomycin and bactrim
52
Causative agent of actinomycosis
| Common clinical form is lumpy jaw
Actinomyces
53
Prevotella
Gram - rod
| obligate anaerobe
54
Main pathogenic bacteria in pregnancy related gingivitis
Can also be isolated from pericoronitis
Implicated in NUP/NUG
Prevotella intermedia
55
Porphyromonas gingivalis
MAJOR player in periodontal diseases
Possesses surface fimbrae
Produces collagenase
56
Neisseria
Colonizes the mucosal surfaces
| Only 2 are are pathogens; Neisseria meningitides (meningitis) and Neisseria gonorrhoeae (gonorrhea)
57
```
Causative for lyme disease (Borrelia burgdorferi) and syphilis (treponema palladium)
Treponema denticola (NUP/NUG)
```
Spirochetes
58
Gram +, aerobic, acid fast bacteria occuring as slightly curved or straight rods
mycobacterium
59
Stimulated by the presence of female sex hormones
| Implicated in pregnancy gingivitis
Camphylobacter
60
Systemic infection of candida may involve
Lungs
Kidneys
Heart
Esophagus*
61
Topical treatment of fungal infections
Nystatin and clotrimazole
62
Systemic treatment of fungal infections
Ketoconazole and fluconazole (Diflucan)
63
Unique characteristics of viruses
Must have host cell
Composed of protein core (capsid)
May have outer lipid bilayer (envelope)
Small
64
What is a complete virus called
virion
65
How are viruses shaped
Helical or icosahedral (20 faces)
66
Function of mRNA
Translation
67
What is transcription
DNA to RNA
68
Examples of RNA viruses
```
Hep A,C,D,E*
Influenza virus
Mumps
Measles
HIV*
```
69
Examples of DNA viruses
```
Hep B
HPV
Hepes I and II
Varicella zoster
Epstein barr virus
```
70
What is an intact Hep B virus called
Dane particle
71
Anti-HBsAg=
No active disease, immune
72
HBeAg=
High infectivity and active infection
73
Example of artifical acquired active immunity
hep b vaccine
74
example of passive immunity
gamma globulin
75
Linked to oropharyngeal malignancy
HPV 16 and possibly HPV 18
76
Gardasil
HPV and there is a vaccination available
77
Varicella zoster virus
Epstein barr virus
Kaposi's sarcoma
Herpes viruses
78
Varicella zoster virus
Causes chickenpox and herpes zoster (shingles) upon reactivation of the dormant virus
79
Causative organism for infectious mononucleosis and may also be implicated in malignancies such as nasopharyngeal carcinoma and Burkitts lymphoma
Ebstein Barr virus
80
Implicated in oral hairy leukoplakia
EBV
81
Kaposi sarcoma herpesvirus
Associated with AIDS
82
Coxsackie virus
Causative organism for herpangina (NOT herpes virus)
83
What are the characteristics of antigens
```
Foreigness (non-self)
High molecular weight
Chemical structural complexity
Antigenic determinants (epitopes)
Dosage, route, and timing of exposure
```
84
Cells of the immune system
```
Made up of leukocytes that are produced in the bone marrow
Granulocytes
Lymphocytes
Monocytes
Dendritic cells
```
85
Granulocytes
neutrophils, eosinophils, basophils
86
lymphocytes
t cells, b cells, natural killer cells
87
monocytes
precursor to macrophages
88
dendritic cells
antigen presenting cells; APCs
89
Characteristics of the innate immune system
present from birth
acute inflammation
dominant system of defense in most organisms
no memory
90
Acute inflammation
A vascular response characterized by edema, redness and pain
91
Nonspecific defenses include
Neutrophils
complement system
phagocytosis
fever
92
Most numerous of the white blood cells
Neutrophils (polymorphonucleocyte)
93
Neutrophils
First line defenders
phagocytes
Relaease powerful enzymes and cytokines
94
When something is wrong with neutrophil functions
periodontal diseases results
95
3 main functions of macrophages
phagocytosis
cytokine production
As an antigen presenting cell, macrophages transport, process, and present antigens
96
Group of white blood cells that destroy tumor cells and virally infected cells
Natural killer cells
97
Natural killer cells
non-specific killers
not phagocytes
kill without antibody
active without prior exposure to antigen
98
Common at sites att he body that are exposed to the external environment and are found in close proximity to blood vessels
Mast cells
99
What happens when mast cells release histamine
capillaries dilate and vascular permeability is dramatically increased leading to edema
100
Two antibodies are capable of activating the complement system
IgG
| IgM
101
When a cell becomes infected with a virus the host cell secretes a group of proteins called
interferons
102
Interferons
stimulate healthy cells to produce proteins that interfere with the synthesis of viral proteins
103
What causes a fever
pyrogens
104
Cellular immunity
```
T-cells
defense against infections (especially mycobacterium tuberculosis and fungal)
delayed hypersensitivity
graft and tumor rejection
regulation of antibody response
```
105
Humoral immunity
```
B cells (plasma cells)
defense against infection (opsonizes bacteria)
allergic response
autoimmunity
```
106
remember pathogens for faster antibody production
B memory cells
107
Types of antibodies
```
IgG
IgM
IgM
IgE
IgD
IgA
```
108
Most adundant ig
only AB to cross the placental barrier
enhances phagocytosis (opsonizes)
complement activator
IgG
109
Main immunoglobulin in secretions (saliva)
| Has j chain and secretory component
IgA
110
First AB made
most efficient in agglutination
complement activator
IgM
111
Most active Ab in response to allergens (bind to mast cells and basophils)
prime defense against parasites
IgE
112
Key antigen presenting cell
critical in initiating immune response
help to regulate adaptive immune responses
Dendritic cell
113
Classification used to describe immunoallergic hypersensitivity reactions
Gell coombs
114
Type I hypersensitivity reaction
anaphylactic reaction
115
type II hypersensitivity reaction
cytotoxic reaction
116
type IV hypersensitivity reaction
cell mediated or delayed reaction
117
type III hypersensitivity reaction
immune complex reaction
118
Allergic reaction that appears very quickly after exposure to previously encountered allergen
IgE is the primary antibody involved and causes release of histamine
Type I
119
T cells (not antibodies) are involved in this hypersensitivity reactions
T cells release cytokines which activate phagocytosis leading to tissue inflammation and injury
Ex) Mantoux skin test
Type IV cell mediated reaction
120
Antigens on a cell surface combine with antibody which leads to complement mediated lysis
EX) Rh and transfusion reactions
Type II cytotoxic reaction
121
Most likely antibiotic class to produce anaphylactic reaction
penicillins
122
The immune complexes are not cleared and persist in blood vessels, filtering organs, and synovial membranes (mechanism for autoimmune disorders)
Type III immune complex reaction
123
Scleroderma
autoimmune disorder that is associated with raynauds phenomenon and generalized widening of the PDL
124
Which antibody is the most abundant antibody in the body
IgG
125
Which type of heptatitis is a dental hygienist least likely to get
hep e
126
in plaque biofilm what makes up the bulk of the deposit
exopolysaccharides
127
which is the first antibody to be produced after birth
IgM
128
which antibody is involved in type I hypersensitivity
IgE
129
Which blood type can be given to all individuals
type O negative
130
microscopically, staphylococci present as
grape like clusters
131
These organisms are implicated in pregnancy gingivits
prevotella intermedia
132
which of the following organisms is causative for pharyngitis (strep throat) ad scarlet fever
streptococcus pyogenes
133
which type of bacteria is most often implicated in root caries
actinomyces
134
which microorganism can be encapsulated with a polysaccharide layer
streptococcus pneumoniae
135
the complement system aids in the immune response by
increasing lysis and opsonization
136
which microscopic technique muct be employed to identify mycobacterium tuberculosis
acid fast staining
137
at what stage of bacterial growth are organisms most susceptible to antimicrobial action
log phase
138
which bacteria is an early colonizer that is associated with the tongue
streptococcus salivarius
