exam 1 lecture 1 and 2 Flashcards
(97 cards)
1
Q
3 great enimies of humanity
A
fever
famine
war
2
Q
what did people realize was bad for cleanliness in 1900s
A
throwing garbage in the street
3
Q
Grandfathers of microbio
A
Pasteur and Koch
4
Q
Pasteur and Koch ushered in
A
the first golden age of microbiology
5
Q
what was done duing the first golden age of mimcrobio
A
bacterial diseases and pathogens that caused them were defined
6
Q
who discovered peniciliam
A
Fleming
7
Q
purified penicilin to be used during wwII
A
Howard Florey and Ernst Brois Chain
8
Q
Each new antibiotic leads to:
A
Resistant strains of bacteria
9
Q
Vital roles of Microbes
A
breakdown/recycling
Bio-remediation
Nitrogen fixing bacteria
Digestion of food
10
Q
what can bacteria metabolize
A
metabolize anything
11
Q
nitrogen fixing bacteria
A
Rhizbia(legumes)
12
Q
bacteria in remen that breakdown cellulose
A
Reminants
13
Q
lead to the field of microbiology
A
discovery of the microscope
14
Q
what do microbes consist of
A
Parasites
Fungi
Bacteria
15
Q
Most diverse of all living microorganisms
A
Parasites
16
Q
LIfe cycle of microbes
A
complex life cycle needing multiple vertebrate and invertebrate hosts.
may depend on combinations of animals, arthropod, crustacean hosts
17
Q
how fungi live
A
free living - ubiquitous in nature
18
Q
description of bacteria
A
smallest independently living cell
Cytoplasmic membrane surrounded by a cell wall
No organelles
19
Q
How bacteria devide
A
Binary Fission
20
Q
Smallest and simplest infectious agent
A
Viruses
21
Q
What do Viruses need
A
obligate intracellular parasites- require host
22
Q
what makes up a virus
A
Protein coat surrounding nucleic acid(RNA or DNA)
23
Q
When a microbe can only infect certain cells
A
Tissue Tropism
24
Q
Established niche at a particular body site
A
Residents
25
Acquired from the environment and establish themselves biefly
Transients
26
What inhibits transients
Resident bacteria or host immune system
27
Potentially pathogenic organism becomes a resident
Carrier state
28
Where babies get their first microbe
Mother's vagina
29
where bacteria colonize
in place best suited to physiology
30
What facters do bacteria consider when determining location to colonize
Available nutrient
pH (acidic, neutral, or basic)
Redox potential
Resistnace to local antibacterial substances (bile, lysozyme)
Adhesion mediated affinity to receptor on host cells
Microbial interactions (who else is already there- competition and inhibition)
31
Environment of Skin
Dry, slightly acidic, aerobic environment
32
where is bacterial flora is highest
on moist skin (armpits, perineum, between toes
33
how can skin flora exist on skin
resist bactericidal effects of skin lipids and fatty acids(kill extraneous bacteria)
34
Microaerophilic or anearobic gram-positive rods that can grow on sebum and break down skin lipids to fatty acid
Proprionibacteria
35
Bacteria of Mouth and pharynx
Many bacteria that are different in different sites. Lots of strptococci, neisseria and Moraxella
36
bacteria of Orthopharyn
Mostly Neisseria and Strptococci
37
Bacteria of Stomach and small bowel
few organisms (Helicobacter pylori), more towards lower ileum
38
Bacteria of Colon
most abudant and diverse microbiota
39
Bacteria of Feces
25% bacteria, 90% anaerobes
40
Bacteria of Anterior nares
Similar to skin flora, Staphylococcus aureus
41
Primary site of carriage for pathogens
Anterior nares
42
Bacteria Nasopharynx
Similar flora as mouth, Pneumococci, menigococci, haemophilus speices
43
Bacteria of Larynx and Respiratory tract
protected in health by epithelial ceilia and by movement of mucocilary blanket
44
Bacteria of Accessory Sinuses
Normally sterile, protected by epithelium and epithelium and Eustachian tubes
45
Urinary tract bacteria
Sterile in health except for 1cm of distal
46
Vaginal tract bacteria is influenced
Flora is influenced by hormonal fluctuations
47
Vaginal tract flora pre-puberty and after menopause
Mixed nonspeific and relative scanty, like skins flora and colon(high pH)
48
Vaginal tract flora during childbearing years
mostly lactoacillus
| some anaerobic gram-neg rods, gram-pos. cocci and yeast (pH is 3.5-4.0)
49
why lactobacilli are found in childbearing years
due to estrogen, glycogen is deposited in vaginal epithelial
50
Occur when microbes invade noramally sterile locations, or host defenses are reduced
Opportunistic infections
51
Competition between normal flora and potential invaders
Exclusionary effect
52
How priming the immune system works
Microbiota important for development of the immune system
53
persistence and invasion lead to disease
no, organism must also cause damage to host
54
how can a pathological organism cause damage to host
- host response to organism(inflammation) can cause damage or symptoms
- Bacteria can produce toxins that act on host cells
- secrete enzymes that degrade host tissues, cause inflammation and facilitate spread
55
ezymes secreted by bacteria that can degrade host tissue
Collagenase, Proteases, Hydrolytic Enzymes
56
how pathogens can evade the immune response
attack immune effector cells
Secrete enzymes that degrade host effector molecules(antibodies
Change surface structure to evade the immune response
Hide inside host cells
57
steps of Diagnosis of infectious Diseases
Specimen collection
| Identification of organisms
58
how to indentify an organism
Direct examination of organism (microscopy)
Isolation of organism ( selective growth conditions)
Identification of organism (growth characteristics and biochem tests)
Imunological techniques
DNA or sequence based techniques
59
specimen localized in an otherwise sterile location (deep abscess or CSF)
Direct specimen
60
Specimen collection that is the highest quality with the highest risk
Direct specimen
61
When specimen collection must pass through a site containing normal flora
Indirect sample
62
Sample where pathogen and nonpathogenic flora are mixed
Sample from site with normal flora
63
how long between collection and isolation
3-4 hours
64
do all organisms live long outiside body
no, poor viability
65
When is bacterial growth after collection a problem
pathogen found in low numbers
66
description of sample transport media
- Buffered fluid or semisolid media
- designed to maintain neutral pH and prevent drying out
- minimal nutrients to minimize growth of bacterial contaminants
67
what is direct ecampination
use of light microscopy to detect bacteria, fungi, and parasites
68
primary bacterial stains
```
crystal violet (purple)
Carbol-Fuchsin (red)
```
69
Counter stains(secondary)
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Safranin (red)
methylene blue (blue)
```
70
what do Gram stains stain
Stain ribonuclear PR inside cells
71
What do acid fast stain stain
stains mycolic acid of acid-fast bacteria
72
Gram-stains examples
```
Safranin(red)
Crystal Violet (purple
```
73
Acid-fast stain examples
carbol-fuchsin (red)
| Safranin (red)
74
how direct immunofluorescenc works
Fluorescein-labeled antibody binds to antigen fixed to slide
75
how indirect Immunofluorescence works
Antibody is fixed to antigen and fluorescein-labeld antiimmunoglobulin bings to fixed antibody to make a antigen-antibody complex
76
media used to isolate specific groups of bacteria
Selective media
77
How selective media works
media contains chem substances that inhibits the growth of one type of bacteria while permitting another
78
Media that distinguishes between closely related species of bacteria based on characteristics on media (color change or colony morphology)
Differential media
79
temp for culturing
35-37 celcius
80
Aerobic conditions for culturing
like normal area (78% N2, 21% O2, 1% Ar, less than 1% for all else
81
When needed CO2 for atmospheric conditions
required by some organisms (2-5% Co2 incubator)
82
Conditions for microaerophilic
5% O2, 10% CO2
83
what needs anaerobic conditions
Anaerobic bacteria that are killed by O2
84
How to create an anaerobic envirnoment
Anaerobe chamber( contains catalyst that reacts with residual O2)
85
What are culture characteristics
Nutritional requirements, pigment productions
86
what are done in biochemical tests
Ability to attack various substrates or produce metabolic by-products
87
the ability to interact with antibodies
Serology
88
Whats to characterize colonies
```
Culture characteristics
biochem
toxin production and pathogenicity
antigenic structure
genomic structure
```
89
Evidence of Cytopathic effects
Viral infections
90
Evidence of Cytopathic effects of viral infections
```
Morpholgical changes to the cells (host tissues, cells lines)
Immunologic tests (antibodies against virus can be detected in blood)
```
91
what antibody and antigen produce when they interact in an immunological test
Precipitate
92
Cross linking of red blood cells
Hemagglutination
93
Viruses can cause
Hemagglutination
94
how to neutralize Hemagglutination from viruses
Antibodies from patient's blood against suspected virus
95
Use of horse/sheep Red Blood cells, which cross-react to antibodies agaist EBV, resulting in agglutination of red blood cells
Mononucleosis test
96
When Target DNA is bound to a membrane and complementary DNA probe attached to a color producing enzyme is reacted with membrane. Signal is produced only if DNA finds it's target(positive test)
DNA Hybridization and Probes
97
DNA specific “primers”
are used to amplify a target DNA molecule. A product signifies
target is present in sample (positive result).
Polymerase Chain Reaction (PCR)
