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Flashcards in Lab Practical 2 Deck (205)
1

What type of gram stain is this?  Positive or Negative

Gram negative (pink)

2

What type of gram stain is this?  positive or negative

Gram positive (purple)

3

What shape is this cell?

coccus

4

What shape is this cell?

dipolococci

5

What arrangement are these cells in?

streptococci

6

What is this arrangement?

tetrad

7

What is this arrangement?

Staphylococci

8

What shape is this cell?

Bacillus

9

What shape is this cell?

Spirochette (Corkscrew)

10

What is the cell arrangement?

dipolobacillus

11

What is this arrangement?

streptobacilli

12

Staphylococci are gram _____ cocci.

positive

13

Staphylococci are typically arranged in _____.

grape like clusters

14

Staphylococci are facultative ______.

anaerobes

15

Staphylococci are members of the _____ family

Micrococcaceae

16

Staphylococcal species can be found normally on the skin and in the _______, including the nasopharyngeal cavity.

upper respiratory tract

17

Staphylococcus aureus colonizes ____% of healthy adults.  In our lab class we see levels that average 30-50%.

15-30%

18

Staphylococcal species are harmless and occasionally result in minor skin infections.  When they are introduced below the skin barrier, they can cause _______.

systemic infections

19

The most relevant coagulase negative staphylococci are _______ and _________.

Staphylococci epidermidis

Staphylococci saprophyticus

20

The most relevant coagulase positive staphylococci is _______.

Staphylococcus aureus

21

_____ is an enzyme produced most notably by Staphylococcus aureus.

Coagulase

22

In the presence of fibrinogen in blood (plasma), it forms fibrin clots, resulting in clotting of the blood.

Coagulase

23

______ is a frequen inhabitant of human surface tissues, inlcuding mucous membranes, considred to be part of the normal human microflora. 

Staphylococci epidermidis

24

______ is not usually pathogenic, but it may cause serious infections if it has an unusual opportunity for entry; cardiac surgery, patients with implanted devices or artificial oints and indwelling intravenous catheters.

Staphylococci epidermidis

25

_______ is the leading cause of cystitis in women and is a common pathogen associated with UTIs

Staphylococci saprophyticus

26

______ causes 10-20% of all urinary tract infectiosn in young sexually active women. 

Staphylococci saprophyticus

27

Staphylococci saprophyticus is considered _____.

not to be normal flora

28

_________ is often found among the normal flora of a healthy person.  Colonization typically occurs in the nasal cavity, thorat, or on the skin.

Staphylococcus aureus

29

Staphylococcus aureus can also cause a variety of diseases and is often referred to as the _____ of all species of Staphylococci.

most virulent

30

The two distinct categories of diseases causesd by Saphylococcus aureus are _______ and ______.

pyogenic infections

exotoxin mediated disease

31

________ is a pus producing infection typically of the skin and wounds.

pyogenic infections

32

Examples of _____ infections include boils, infected hair follicles (folliculitis), carbuncles, and impetigo.

pyogenic infections

33

_______ occur when Staphylococcus aureus produces exotoxin(s) that result in disease.

exotoxin mediated diseases

34

Three examples of exotoxin mediated diseases.

scaleded skin syndrome

toxic shock syndrome

staphylococcal food poisoning

35

________ is caused by production of the exotoxin exfoliatin.

scalded skin syndrome

36

_______ is caused by production of the exotoxin toxic shock syndrome toxin (TSST) which acts as a "superantigen" resulting in shock and even death.

toxic shock syndrome

37

______ is caused by the production of enterotoxins by some Staphylococcus aureus.

staphylococcal food poisoning

38

______ results in rapid onset food illness = nausea, vomiting, retching, and abdominal cramping developing just a few hours post ingestion of contaminated food.  (last 1-2 days)

Staphylococcal food poisoning

39

Two types of Methicillin resistant Staphylococcus aureus (MRSA)

Noscomial (Hospital Acquired Infection or HAI) MRSA

and

Community-Acquired (CA) MRSA

40

________ is acquired in hospitals and nursing homes where patients often have open wounds, indwelling devices and are immunocompromised.  This group is more susceptible than the general public.

Nosocomial (Hospital Acquired Infection or HAI) MRSA

41

________ this is acquired by healthy people outside of a hospital setting.  Most often this occurs as a skin boil.  Direct contact is high risk and can often be seen spread in locker rooms, on gym equipment, dorms.

Community-Acquired (CA) MRSA

42

MRSA strains are resistant to ____ antibiotics which include the -cillins.

beta-lactam

43

MSA is also known as _____.

Mannitol Salt Agar

44

Mannitol Salt Agar selects for ______ species because of the high salt concentration.

Staphylococcus species

45

Mannitol Salt Agar (MSA) is both differntial and _____.

selective

46

Mannitol fermentation in MSA detects pH change by _____.

phenol red

47

Phenol red in MSA changes to _____ for a positive acid fermentation of mannitol.

yellow

48

SBA is known as ______.

sheep's blood agar

49

Sheeps blood agar is a _____ medium.

non-selective

50

Sheep's blood agar (SBA) is differential for ______.

RBC hemolysis

51

______ produces a toxin that lyses RBCs resulting in beta hemolysis.

Staphylococcus aureus

52

_______ does not have the ability to lyse RBCs and results in Gamma hemolysis.

Staphylococcus epidermidis

53

On the mannitol (MSA) media a result of positive growth (yellow) indicates a strong likelihood that _____ is present.

Staphylococcus aureus

54

If mannitol fermentation (yellow) indicates Staphylococcus aureus is likely a _______ test would be needed to be done for confirmation.

coagulase testing

55

Coagulase testing differentiates Staphlyococcus aureus from ________.

other Staphylococcus species.

56

Coagulase differentiates coagulase _____ and ____.

positive

and

negative

57

Coagulase testing consists of using a slide with two wax penciled circles.  One circle contains ______ and the other contains water.

rabbit plasma

58

The water is a control to verify that the strain does not display ________.

auto-agglutination (a false positive)

59

In coagulase testing once the water and rabbit plasma are on the slide.  The stick end of a ______ is used to collect cells and emulsify in the water.

sterile swab

60

In a coagulase test you watch for clumping within _____.  The clumping will become more visible if each sample is rocked gently.

15-20 seconds of adding the bacterial cells to the plasma

61

In coagulase testing a positive result is ________.

clumping, white flecks in the plasma

62

63

If the coagulase specimen shows clumping only when emulsified in the plasma and ther is no auto aggultination the test is _____.

positive

64

If there is no clumping in either the water or rabit plasma, it is a _____.

negative coagulase

65

If a coagulase testing shows clumping in the water, this auto agglutination indicates _______.

inconclusive test results

66

An inconclusive coagulase test usually occus if the sample is ____.

old

67

All ______ species show positive growth on MSA.

Staphylococci

68

S. aureus shows _____ hemolysis on SBA.

beta

69

Gamma hemolysis on SBA is seen in ________ and _______.

s. epidermidis

and

s. saprophyticus

70

Mannitol fermentation in S. aureus is _______.

positive (yellow)

71

Mannitol fermentation is negative for _________ and ____________.

S. epidermidis

and

S. saprphyticus

72

S. epidermidis and S. saprophyticus test _____ for coagulase.

negative

73

What species of stphylococci is negative for mannitol fermentation, coagulase, and hemolysis (gamma)?

S. epidermidis

and

S. saprophyticus

74

In order to differentiate s. epidermidis and s saprophyticus a ______ test needs to be done.

novobiocin sensitivty test (antibitoic assay)

75

S. epidermidis is _____ to the novobiocin test.

sensitive (killed white circle forms)

76

S. saprophyticus is _____ to the novobiocin test.

resistant (no clearing of agar)

77

S. aureus is _____ to novobiocin test.

resistant (no clear circle)

78

What tests are done to confirm S. epidermidis?

MSA = positive growth

MSA = no fermentation = red/pink

Coagulase = negative = no clumping

Hemolysis = negative = gamma

Novobiocin = sensitive = clear circle in agar

79

80

Streptococcal species are gram _____.

positive

81

Streptococcal species are facultative _______.

anaerobes

82

Streptococcal grow in _____ or _____.

pairs or chains

83

Streptococcal species are commonly found in the mouth, respiratory tract and _______.

skin

84

Isolation of Streptococcus is typically done using _____.  SBA is not selective for streptococcus.

blood agar

85

Streptococcus pneumoniae is a _____ inhabitant of the human upper respiratory tract. 

normal

86

The most common diseases include bacterial pneumonia, otitis media, and _____ for streptococcus pneumonia.

meningitis

87

Streptococcus pneumonia often forms ______ shape.

diplococci

88

_______ is a frequen pathogen of humans and is associated with Strep throat, Scarlet fever, and necrotizing fasciitis.

Streptococcal pyogenes

89

Streptococcoal pyogenes is not normal flora, although a small % of people will carry this in their ______ without disease symptoms.

respiratory tract

90

_______ was formerly known as Streptococcus faecalis.

Enterococcus faecalis

91

_______ is normal flora of the human GI tract.  It is also associated with opportunistic urinary, wound and skin infections.

Enterococcus faecalis

92

Streptococcus agalactiae is a group _____ strep.

B

 

93

Streptococcus agalactiae is a normal inhabitant of GI tract and _____ for some and can be nosocomial/opportunistic as well.

genituourinary tract

94

______ can cause sepsis, pneumonia, and even meningitis in newborns when transferred during passing through the birth canal.

Streptococcus agalactiae

95

_____ infections of the blood, tissue and joint infections has been reported in adults.

GBS

96

Two members of the viridans group are _______ and _______.

Streptococcua mutans

Streptococcus salivarius

97

Viridians (S. mutans and S. salivarius) are common ____ microflora which may enter the blood steam.

oral

98

Viridians (S. mutans and S. salivarius) are oral microflora that may enter the blood steam during dental work or when brushing/flossing leading to opportunisitc disease and _____.

endocarditis

99

Streptococci are classified based on their _________ on blood agar and thier ______.

hemolytic properties

serologic groups (lancefield)

100

_____ hemolysis (partial) results in a greenish color on blood agar.

alpha

101

_____ hemolysis (complete) results clear areas around bacterial colonies on blood agar.

Beta

102

______ hemolysis refers to no hemolysis.

gamma

103

______ grouping is a method of grouping Streptococcal bacteria based on composition of bacterial antigens found on their cell wall. (carbohydrate antigens)

lancefield

104

There are several Lancefield serogroups, group ____, _____.  Not all groups are human pathogens.

A-H, K-V

105

Streptococcus pyogenes is a group ____.

A streptococci

106

Steptococcus agalactiae is group ____ streptococci.

B

107

Enterococcus species and some viridian strains are Group ___ streptococci.

D

108

______ has no group specific antigen.

Streptococcus pneumoniae

109

Group A and B streptococci demonstrate ____ hemolysis.

beta

110

Group D streptococci demonstrates ______ hemolysis.

alpha (parital)

111

S. penumoniae and viridans demonstrate _____ hemolysis.

alpha (partial)

112

______ is useful for differentiating beta hemolytic streptococcus. (GAS and GAB)

Bacitracin

113

_________ is useful for differentiating alpha hemolytic streptococcus (S. pneumonia/Viridians)

Optochin

114

S. pyogenes is _____ to bacitracin (antibiotics).

sensitive

115

S. agalactiae is _____ to bacitracin (antibiotic)

resistant

116

117

S. pneumoniae is ____ to optochin (antibiotic)

sensitive

118

S. salivarius is ____ to optochin (antibiotic)

resistant

119

Streptococcal identification is done by ______ determination on SBA.

hemolysis

120

Streptococcus specieses with alpha hemolysis

S. pneumoniae

S. salivarius

121

Streptococcus species beta hemolysis

S. pyogenes

and

S. agalactiae

122

Streptococcus gamma hemolysis

E. faecalis

123

________ is an ezyme that breaks down toxic hydrogen peroxide (H2O2) into H2O and O2.

catalase

124

125

____ is often used as a disinfectant in wounds, and the bubling that is sen is due to the production of O2 gas.

hydrogen peroxide

126

Any cell that uses O2 or can live in the presence of O2 must have a way to get rid of the ____.

peroxide

127

One way to remove peroxide is to make the enzyme _____.

catalase

128

Many living cells produce catalase, including several ___ and even human RBCs.

GNR

129

All _________ species produce the enzyme catalse and are positive for catalase.

staphylococcus

130

All ____ species (with the possible exception of some Enterococci) do not produce catalse and are catase negative.

stretptococcus

131

A catalase test will differeniate between ______ and _____.

staphylococcus and streptococcus

132

In a catalase test you take a two samples of your bacteria and place with a swab on opposite ends of a microscope slide.  To determine which is catalse positive and negative you must add ____ to each sample on the slide and observe.

hydrogen peroxide

bubbles = positive

no bubbles = negative

133

In a negative catalase specimen there is no catalase enzyme to hydrolyse the ______.

hydrogen peroxide

134

A _____ is used by clinicians to test patients for Group A Streptococcus.

rapid strep test

135

____ can cause a variety of illnesses including Strep throat, scarlet fever, and rheumantic fever.

GAS

(group A strep)

136

The rapid strep test can be done in ____, sending off a throat culture takes days.

minutes

137

The rapid strep test allows ____ to begin immediately, instead of having to wait for a culture.

treatment

138

____ are possible with rapid strep tests, so cultures are still send out even after a negative rapid strep test.

False negatives

139

__________ are proteins made by the immune system that bind specifically to a specific antigen.

Antibodies (Ab)

140

The rapid strep test is able to recognize the presences of GAS antigens becuse there is a series of _____ imbedded in the test strip.

antibodies

141

The GAS strep antibodies on the rapid strep test are located at the bottom, but they move up the strip via ______ (as test liquid moves up). This will occur is GAS antigen bound ____.

capillary action

to it or not

142

Between the two blue markers on a rapid strep test if a line appears parallel to both blue areas the test for GAS is _____.  The top line indicates the test was done correctly (GAS moved up the strip).  The bottom line detects antigens for GAS.

positive

143

During a rapid strep test if only one line appears between the two blue lines (closer to the top) the test is considered _____.

negative

144

Reagent A and B are mixed together in a small test tube.  A throat swab is inserted into the tube.  The reagents kill any bacteria present and cause any GAS antigens present to be _____ during a rapid strep test.

released into the solution

145

Is SBA selective for Streptococcus?

no

146

S. pyogenes is ____ in a rapid strep test.

positive

147

S. algalactiae is ____ in a rapid strep test.

negative

148

____ hemolysis is when there is no change in red blood cells.

gamma

149

_____ hemolysis is when there is complete lysis of red blood cells.  (agar becomes clear or tinted yellow)

beta

150

______ hemolysis is partial destruction of RBCs.  (greenish color)

alpha

151

S. epidermidis is ____ for catalase.

positive

152

S. salivarius is ____ for catalse.

negative

153

_____ is only useful to identify streptococcus vs stphylococcus after gram staining.

catalase

154

ENTEROBACTERIACEAE IS THE FAMILY NAME FOR ______.

ENTERICS

155

All enterics gram ____ _____.

negative rods

156

All enterics are _____.

facultative anaerobes

157

All enterics are _____ for catalase.

positive

158

All enterics ______ lactose.

ferment

159

All enterics are oxidase _____.

negative

160

The two types of strains of Escherichia coli are ____ and ____.

commensal and pathogenic

161

Pathogenic strains of E. coli cause UTIs, gastintestinal and _____.

meningitis

162

Pathogenic strains of E. coli cause ____, gastintestinal and meningitis.

UTIs

163

Citrobacter freundii is ____ in the GI and enviornment

commensal

164

Citrobacter freundii is an _____ pathogen that causes greater than _____ of nosocomial infections.

opportunisitic pathogen

> 20%

165

Enterobacter aerogenes is a _______ _______ pathogen

nosocomial opportunistic

166

The most common sites of infection of Enterobacter aerogenes is teh _____ and _______.

urinary and respiratory tract

167

Enterobacter aerogenes is a _____.

fecal coliform

168

Klebsiella pneumoniae is _____ in the mouth, skin and intestines.

normal flora

169

Klebsiella pneumoniae is ______ and not usually a problem for healthy people.

nosocomial

170

171

Klebsiella pneumoniae causes hemorrhage resulting in sputum called ____.

currant jelly sputum

172

_____ pneumoniae can cause pneumonia, necrosis, and inflammation.

klebsiella

173

Klebsilla pneumoniae can cause pneumonia, ____, and inflammation.

necrosis

174

Salmonella typhimurium is not ____ in humans.

normal

175

Salmonella typhimurium is usually found in the GI of infected _____ and ____, as wellas on their skin (reptiles)

domestica animals and wild animals

176

Salmonella typhirmurium causes _______ in humans/other mammals.

gastoenteritis

177

Salmonella typhimurium can cause more sever symptoms resembling ______.

typhoid fever (fever, rash, splenomegaly)

178

Salmonella typhimurium is a ____ pathogen.

strict

179

Proteus vulgaris can be found in the GI of _____ and _____.

humans and animals

180

Proteus vulgaris demonstrates urease ____.

activity

181

Proteus vulgaris increases crystal formation causing _____.

kidney stones

182

Proteus vulgaris has swarming motility because of the ____ flagella.

peritrichous

183

Serratia marcescens is an _____ pathogen.

opportunistic

184

Serratia marcescens is commonly found in soil, water, plants, and on ____.

animals

185

Serratia marcescens is an oppotunistic pathogen of ___.

many areas

186

Alcaligenaceae is the family for ______.

Alcaligenes faecalis

187

Alcaligenes faecalis is normal flora for ____.

birds.

188

Alcaligenes faecalis is generally not ____.

pathogenic

189

Alcaligenes faecalis can cause ______.

opportunistic UTI

190

Pseudomonas aeroginosa is a nonsocomial opportunistic pathofen of ____.

almost every tissue.

191

Pseudomonas aeroginosa can grow in minimal _____ and form biofilms on surfaces.

nutrient conditions (water)

192

Pseudomonas aeroginosa is commonly found in soil and water, surfaces of plants and on the surfaces of _____.

animals

193

194

195

______ test is helpful in differentiating between Staphylococcus and Streptococcus.

catalase

196

Once you confirm a GPC, you should then perform a ______ test.

catalase

197

A ____ test is helpful in differentiating S. aureus from other coagulase negative sepceis.

coagulase

198

Only do coagulase tests on ________ species.

staphylococcus

199

A catalase test with bubbles is ______

staphylococcus

200

A catalase test without bubbles is _____.

streptococcus

201

The gastointestinal tract of humans is the normal habitat for many different ______.

GNRs

202

E. coli is important to digestion and ____ production as a normal inhabitant of the intestinal tract.

vitamin

203

E. coli species are also a common cause of _____ and intestinal diseases.

utis

204

Citrobacter freundii is found is an oppotunisitic pathogen that causes nonsocomial infections in the _____.

blood

205