Brainscape's Knowledge GenomeTM

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


See full index

MOD > Intro to Bacteria Part 1 > Flashcards

Intro to Bacteria Part 1 Flashcards

1
Q

Prokaryote vs. Eukaryote (generally)

A

eukaryotes contain membrane bound nuclei, while prokaryotes do not

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

Archaeon

A

microorganisms found in extreme environments; possibly the earliest forms of cellular life on earth

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

Gram positive stain color

A

Blue

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

Gram negative stain color

A

Red

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

Gram positive cell wall

A

very thick cell wall with extensive amino acid cross-linking; made of peptidoglycan, teichoic acid, polysaccharides and other proteins

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

Gram negative cell wall

A

simple cross linking pattern; cytoplasmic membrane, peptidoglycan layer, THIN peptidoglycan layer (no teichoic acid), LPS layer, porins in outer membrane

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

LPS constituents

A

O-specific side chain/O-antigen, core polysaccharide, Lipid A

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

Gram negative endotoxin

A

Lipid A; causes fever, diarrhea, endotoxic shock

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

What can pass through a G+ cell wall?

A

antibiotics, dyes, detergents

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

What substances cannot pass through G- cell wall?

A

negatively charged, antibiotics that attack peptidoglycan

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

Key differences between G+ and G- cell wall?

A

G+: 2 layers, low lipid content, no endotoxin, no porin, vulnerable to lysozyme and penicillin
G-: 3 layers, high lipid content, Lipid A toxin, porin channels, resistant to lysozyme and penicillin

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

6 Classic most medically relevant G+ pathogens

A

Streptococcus, Staphylcoccus, Bacillus and Clostridium (spores), and Corynebacterium and Listeria (non spores)

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

G- cocci

A

Neisseria, Moraxella

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

G- spiral shaped

A

Spirochetes (Treponema pallidum)

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

Mycobacteria unique features

A

weakly G+ but stain better with acid-fast stain

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

Spirochetes unique features

A

G- wall but must be seen with dark field microscope (size); contain additional outer membrane with very few proteins and periplasmic flagella

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

Mycoplasma unique features

A

no cell wall, not G+ or G-

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

G+ obligate aerobes

A

Nocardia, Bacillus cereus

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

G+ Facultative anaerobes

A

Staphylococcus, Bacillus anthracis, Cornyebacterium, Listeria, Actinomyces

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

G+ Microaerophilic

A

Enterococcus, Sterptococcus

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

G+ Obligate anaerobes

A

Clostridium

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

G- obligate aerobes

A

Neisseria, Pseudomonas, Bordetella, Legionella, Brucella

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

G- facultative anaerobes

A

most G- rods

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

G- Microaerophilic

A

Spirochetes (Treponema, Borrelia, Leptospira), Campylobacter

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

G- Obligate anaerobes

A

Bacteroides

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

Acid-fast obligate aerobes

A

Mycobacterium, Nocardia

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

Oxygen spectrum of Mycoplasma

A

Facultative anaerobe

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

Obligate aerobes

A

glycolysis, Krebs, and ETC

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

Facultative anaerobes

A

aerobic bacteria that contain catalase and superoxide dismutase; CAN grow in absence of oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Microaerophilic bacteria

A

no electron transport system, tolerate low amounts of oxygen and have superoxide dismutase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Obligate anaerobes

A

No enzymes to defend against oxygen, does not like oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Virulence definition

A

degree of organism pathogenicity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

pili

A

straight filaments arising from bacterial cell wall, serve as adherence factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

organisms with pili and cells they attach to

A

N. gonorrhea: cervical and bucal cells
E. coli and C. jejuni: intestinal epithelium
B. pertussis: ciliated respiratory cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Capsules

A

Protective walls around cell membranes of bacteria composed of simple sugars

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Capsule of Bacillus anthracis

A

capsule made up of amino acid residues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Why do capsules contribute to the virulence of an organism?

A

Neutrophils and macrophages are unable to phagocytize encapsulated bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Stains that enable doctors to visualize capsules

A

India Ink stain, Quellung reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

India ink stain

A

stain not taken up by capsule, appears as a transparent halo around cell; Cryptococcus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Quellung reaction

A

bacteria mixed with abs, capsule can swell with water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Endospores

A

formed by G+ bacillus and clostridium; metabolically dormant forms resistant to heat, cold, drying and chemical agents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Endospore protective coat consists of

A

cell membrane, peptiodglycan, cell membrane, keratin-like protein, exosporium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

When do spores form?

A

shortage of needed nutrition, will become active again when appropriate nutrition is available

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Exotoxins

A

proteins released by G+ and G- bacteria that may cause disease manifestations (anthrax, botulism, tetanus, cholera)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Neurotoxin

A

tetanus toxin and botulinum toxin; act on nerves or motor endplates to cause paralysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Enterotoxins

A

exotoxins that act on GI; inhibit NaCl resorption, activate NaCl secretion or kill epithelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Two disease manifestations of enterotoxins

A

Infectious diarrhea (E. coli, V. cholera, C. jejuni, S. dysenteriae), Food poisoning (toxin from food, B. cereus, S. aureus)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Pyrogenic exotoxins

A

cause rash, fever, toxic shock; S. aureus, S. pyogenes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Tissue Invasive exotoxins

A

allow bacteria to destroy and tunnel through tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Endotoxins

A

Lipid A, released when bacteria undergoes lysis, but can be shed from living bacteria; normal part of membrane that sheds off

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Septic shock

A

sepsis that results in low BP and organ dysfunction

52
Q

TNF

A

tumor necrosis factor/cachexin; triggers release of IL-1

53
Q

IL-1

A

triggers release of other cytokines and PGs, vasodilation, hypotension and organ system dysfunction

54
Q

Methods of genetic exchange between bacteria

A

transformation, transduction, conjugation, transposons

55
Q

Transformation

A

uptake of DNA fragments from one bacterium released during lysis

56
Q

Transduction

A

bacteriophage carries piece of bacterial DNA from one bacterium to another

57
Q

Virulent phage

A

infects, reproduces, then lyses bacteria; generalized transduction

58
Q

Temperate phage

A

infect bacteria, but DNA will become incorporated into the bacteria DNA (time bomb); specialized transduction

59
Q

Lysogenic immunity

A

term used to describe ability of an integrated bacteriophage to block a subsequent infection by a similar phage

60
Q

Generalized transduction

A

bacterial DNA mispackaged into phage, which can then go and infect another bacteria without causing it’s death

61
Q

Conjugation

A

sex pilus forms and allows for efficient exchange of plasmid/genetic material between bacteria

62
Q

Transposons

A

pieces of DNA that insert themselves into chromosome without having homology, often responsible for drug resistance

63
Q

Agents and methods used to identify pathogens?

A

smears, gram staining, cultures, molecular techniques, serology, survey for ab positivity

64
Q

Potential pathogens

A

bacteria, viruses, fungi, parasites, prions, mites, etc.

65
Q

Pros of bacterial cultures

A

high specificity, isolates can be tested for ab sensitivity, enables biochem characterization of phenotype, less expensive, does not require special workflow, does not require specialized instrumentation

66
Q

Cons of bacterial cultures

A

low sensitivity, cannot detect nonviable bacteria, biochem phenotype may not agree with genotype, longer time to result for slow-growing bacteria, biosafety concern

67
Q

Pros of NAT methods

A

high sensitivity, rapid turnaround time, detection of nonviable bacteria, reduced biosafety concern, detection of ab-resistant bacteria without an initial culture

68
Q

Cons of NAT methods

A

false positives due to cross reaction, false-negatives, genotype may not agree with biochem results, requires special instrumentation and training, few tests for ab sensitivity are available

69
Q

Differentiating Staph and Strep

A

Staph: cocci cluster together, catalase positive (Staff has a Cat)
Strep: cocci form a strip, catalase negative

70
Q

Hemolytic reactions of strep

A

Beta-hemolytic: completely lyse RBCs on blood agar
Alpha-hemolytic: partially lyse RBC
Gamma-hemolytic: unable to hemolyze (“non-hemolytic” streptococci)

71
Q

C carbohydrate

A

Carb found on cell wall of Strep

72
Q

Group A B-hemolytic Streptococci aka

A

Streptococcus pyogenes

73
Q

Diseases associated with S. pyogenes

A

strep throat, scarlet fever, rheumatic fever, post-strep glomerulonephritis

74
Q

C carb Lancefield group of S. pyogenes

A

Lancefield group A

75
Q

M protein

A

Major virulence factor in S. pyogenes, inhibits complement and protects from phagocytosis

76
Q

Streptolysin O

A

enzyme in beta-hemolytic group A strep, inactivated by oxygen, destroys RBC and WBC, ANTIGENIC (may order ASO on pt)

77
Q

Streptolysin S

A

oxygen stable enzyme beta-hemolytic group A strep, not antigenic

78
Q

Pyrogenic exotoxin

A

exotoxin produced by only a few strains of beta hemolytic group A strep, superstimulates T cells to pour out inflammatory cytokines

79
Q

streptokinase

A

activates proteolytic enzyme plasmin, breaks up fibrin clot

80
Q

Beta-hemolytic Grp A strep causes what diseases by local invasion or exotoxin release

A

Strep pharyngitis, Strep skin infection, scarlet fever, Strep TSS

81
Q

Beta hemolytic Grp A strep causes what diseases by delayed antibody mediated diseases

A

Rheumatic fever and glomerulonephritis

82
Q

Sxs and tests for Strep pharyngitis

A

red swollen tonsils and pharynx, purulent exudate on tonsils, high temp, swollen LNs
RADT test: group A carb

83
Q

Sxs of Strep skin infections

A

folliculitis, pyoderma, erysipelas, cellulitis, impetigo

84
Q

Erysipelas

A

strep infection of superficial skin, raised, bright red rash with a sharp border that advances from the initial site of infection

85
Q

Pyoderma

A

pustule on face or extremity that breaks down after 4-6 days and forms a thick crust, leaving a depigmented area

86
Q

Necrotizing fascitis

A

certain strains of grp A b-hemolytic strep have M proteins that block phagocytosis; swelling, heat, redness at site of infection, large blisters form and skin and muscle may die

87
Q

Fournier’s gangrene

A

form of necrotizing fascitis in male genital area and perineum

88
Q

Scarlet fever

A

sore throat and pyrogenic or erythrogenic toxin and fever/rash; spares the face!

89
Q

Strep TSS

A

pyrogenic toxin

90
Q

Erythema marginatum

A

nonpruritic rash typically occurring on trunk and extremities, not face; occurs in patients with rheumatic fever

91
Q

Tinea corporis

A

rounded lesion that typically has a fine scale and may cause alopecia; central clearing and raised borders; pruritic

92
Q

Erythema migrans

A

bull’s eye appearance, Lyme disease; central erythema and necrosis

93
Q

Erythema multiforme

A

maculopapular rash located on palms and feet that generally spreads; can result from drug rxn or viral and bacterial infections; bull’s eye appearance, pruritic, blanches away slowly

94
Q

Erythema nodosum

A

erythematous macules that are painful; usually occurs on shins

95
Q

Rheumatic fever presentation

A

children 5-15 yrs of age, typically follows strep pharyngitis; fever, myocarditis, joint swelling, chorea, subcutaneous nodules, erythema marginatum

96
Q

Acute post-strep glomerulonephritis

A

ab-mediated inflammatory disease of glomeruli; antigen-antibody complexes deposit in BM of glomeruli

97
Q

Presentation of acute post-strep glomerulonephritis

A

child in office complaining of puffy face, dark urine; may have hypervolemia/high BP; recent history of throat or skin infection

98
Q

Grp B Streptococci genus/species

A

Streptococcus agalactiae

99
Q

Age-group most commonly affected by Grp B Strep

A

neonates; most common cause of neonatal meningitis, pneumonia, and sepsis

100
Q

Grp B Strep presentation

A

fever, vomiting, poor feeding, irritability

101
Q

3 most common pathogens associated with meningitis in neonates and infants <3mo?

A

E. coli, L. monocyotogenes, grp B Strep

102
Q

Most common bacterial cause of meningitis later in life

A

Neisseria meningitides, Haemophilus influenzae

103
Q

Viridans Grp Streptococci hemolytic rxn

A

alpha-hemolytic

104
Q

Where are Viridans Grp Streptococci normally found?

A

GI tract, nasopharynx, gingiva

105
Q

Associated infections of Viridans Grp Strep

A

dental infections, endocarditis, abscesses

106
Q

Presentation of Subacute Bacterial Endocarditis

A

low-grade fever, fatigue, anemia, heart murmur secondary to valve destruction

107
Q

Presentation of acute infective endocarditis

A

shaking chills, high spiking fevers, rapid valve destruction

108
Q

Bacteria commonly found in brain or abd organ abscesses

A

Anginosus species (Strep. intermedius), microaerophilic

109
Q

Grp D Strep sub groups

A

Enterococcus and non-enterococci

110
Q

Hemolytic pattern of Grp D Strep

A

alpha- or gamma-hemolytic

111
Q

Normal residence of enteroccoci

A

human intestines/normal bowel

112
Q

Unique growth characteristics of enteroccus

A

ability to grow in 40% bile or 6.5% NaCl

113
Q

Common diseases associated with Enterococcus

A

UTI, biliary tract infection, bacteremia, subacute bacterial endocarditis

114
Q

Enterococcus in nosocomial infections

A

second to third most common cause of hospital acquired infections

115
Q

Drug resistance of Enterococci

A

resistant to nost G+ bacteria; vancomycin and ampicillin, esp

116
Q

Non-enterococci common genus/species

A

Strep bovis and equinis

117
Q

Growth conditions of Strep bovis

A

40% bile acid (but not 6.5% salt!)

118
Q

S. bovis in colon cancer

A

remarkable association, not sure if it’s a cause or marker?

119
Q

Strep pneumoniae disease manifestations

A

bacterial pneumonia and meningitis in adults, otitis media in kids

120
Q

Quellung reaction for Strep pneumoniae

A

capsule swells

121
Q

Optochin sensitivity for Strep pneumoniae

A

growth inhibited by optochin (unlike S. viridans)

122
Q

Most common cause of pneumonia in adults

A

S. pneumoniae

123
Q

Presentation of pneumococcal pneumonia

A

rigors, high fevers, chest pain with respirations, SOB, yellow-green sputum

124
Q

Three organisms associated with otitis media

A

S. pneumoniae, H. influenzae, M. catarrhalis

125
Q

Who is given the pneumococcal vaccine

A

immunocompromised, elderly, asplenic or HIV positive individuals

126
Q

Emerging abx resistance of S pneumoniae

A

penicillin ,erythromycin, sulfamethoxazole, chloramphenicol

MOD (34 decks)

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