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Flashcards in Lab Final Deck (150):
1

Define erythroblastosis fetalis.

Fetal RBC destruction

2

Eosin Methylene Blue Agar meaning?

Poor/no growth, inhibited by eosin and methylene blue, Gr +

Good growth, not inhibited by eosin and methylene blue, Gr -

Green metalic growth, ferments lactose with acid, coliform

3

What does the GasPak Anaerobic System do?

Creates anaerobic, microaerophilic, or CO2 enriched conditions

4

What is EMB used for?

Fecal coliform

5

How is a motility test done?

Stabbing the broth with a straight needle.

6

When is blood agar used?

Isolation and cultivation of bacteria; Differentiate bacteria based upon hemolytic characteristics

7

With wet mount and hanging mount looking for motility, what could cause a false negative?

Water dries up.

Too many microbes on slide - no room to move.

If a culture is too old or cold.

8

What is the Acid-Fast Stain Technique?

C A M

Heat fix, carbolfuchsin, water, alcohol, water, MB, water, blot

9

What is in the GasPak?

sodium borohydride and sodium bicarbonate

10

The incubation of nitrate broth after the addition of reagents and zinc, what is the positive result?

No color change

11

How is this broth described?

Flocculence (clumping)

12

What is the name of the bacteria that grows between 20 degrees and 45 degrees C.?

Mesophiles

13

What is EMB used for?

Fecal coliform

14

Can antimicrobial disk diffusion be determined by the clearning method alone?

No. A dimetral intrepretertive chart is needed.

15

What kind of broth is phenol red?

Differential

16

Decarboxylation test tubes.  What is the meaning?

No color change, no decarboxylation, -

Yellow, fermentation; no decaroboxylation, -

Purple, decarboxylation w decarboxylase, +

17

What is EMB used for?

Fecal coliform

18

In Ex. 1-1, what was the purpose of the hand cleaning agents exercise?

Evaluate the effectiveness of a variety of hand-washing agents

19

What is the Endospore Stain Technique?

20

Phenol Red Broths meaning?

Seletive or differential?

Yellow broth, bubble in tube, fermentation with acid gas, A/G

Yellow broth, no buble in tube, fermentation w acid and no gas A/-

Red broth, no bubble in tube, no fermentation, -/-

Pink broth, no bubble, degragation on peptone, K

Differentiate Enterobacteriaceae

21

How is a wet mount made?

By placing a drop of water on a slide and covering it with a cover slip

22

If you get good growth in eosin methylene blue, EMB, what is the presumptive ID?

Gram negative

23

Sketch the Quadrant Streak Pattern

24

How is a hanging drop slide prepared?

Depression slide with a petroleum jelly ring.

Droplet is hanging on cover slip and not toughing the slide.

25

At what pH does Neural red indicate?

Indicates red at pH less than 6.8 - acidic conditions

26

What does eosin methylene blue, EMB, contain?

Gelatin, lactose eosin Y and methylene blue

27

What microbe does MacConkey agar detect?

Enterobacteriacease to ferment lactose

28

Sketch the Simple Streak Pattern

Note: no cross streak as seen in photo

29

What is the formulas for Dilution and Origional Cell Density

V1D= V2D2

OCD = CFU / (D x v)

30

MacConkey Agar meaning?

Is it selective and/or differential?

Poor/ no growth, inhibited by CV, Gr +

Good growth, not inhibited by CV, Gr -

Red, produces acid from lactose fermentation, coliform

Selective and differential for Enterbacteriaceae

31

What is the negative stain technique?

SOSD

Negrosin, add organism, slide, dry

32

In Ex. 1-1, hand cleaing agent, what is a positive result look like?

Any finger contamination that grows on nutirent agar is a positive result

33

Blood agar meaning?

34

List the five types of oxygen tolernace and draw each

35

Define decontamiantion

The reduction of the number of pathogens to a level to handle without PPE

36

What does the fermintation of glucose begin with?

Pyruvate

37

How do you test for an environment favorable for streptolysins?

Streak-stab technique.

38

Catalase Test meaning?

What is catalase?

Bubbles, catalase is present, +

No bubbles, catalase is absent, -

Catalase converts hydrogen peroxide H2O2 to H2O and O2

39

Nitrate Reduciton Test tubes with zinc meaning?

Red, nitrate reduction to nitrite, +

After adding zinc, no color change, nitrite to nitrogen, +

After adding zinc, red color, no nitrate reduction, - 

40

What is in the GasPak?

sodium borohydride and sodium bicarbonate

41

What is the heat fixing technique?

Loopful of water, bacteria, air dry, flame

42

What causes hemolysis?

Streptolysin O - oxygen labile, anaerobic conditions

Streptolysin S - oxygen stable, anaerobic conditions too.

43

What is tested in blood agar? Which type has the most, middle, and no hemolysis?

Hemolysins to break RBC. beta-, alpha-, gamma-hemolysis has no media change.

44

How can motility be best observed?

using low or high-dry lenses

45

MacConkey agar uses neural red dye. At what pH does it indicate?

0-6.8 pH. Organisms that ferment lower the pH.

46

Citrate Utilization Test meaning?

Selective or differential?

Blue, citrate is utilized, +

No color change, citrate is not utilized, -

Differentiates Enterobacteriaceae

47

What is phenol red used for?

To differentiate enterobacteriacase from other Gram-negative rods.

48

Tripple Sugar Iron Agar meaning?

49

What is the name of the bacteria that grows between 0 degrees and 20 degrees C.?

Psychrophiles

50

 Starch Hydrolysis (Amylase Test) meaning?

Clearing around growth, alpha-amylase present, +

No clearing, no alpha-amylase present, -

alpha-amalyase hydrolyze starch

51

Which microbe is motility an important characteristic?

Enterobacteriaceae

52

Gelatine Hydrolysis (Gelatinase Test)?

Geletin is solid, no gelatinase is present, -

Gelatin is liquid, gelatinase is present, liquidfaction, +

53

What is a disinfectant?

A germicide for use on surfaces.

54

Taken from an anaerobic jar, how are these cultures described?

55

What is the chemistry for the motility test?

Reduction of 2,3,5 TTC by metabolizing bacteria changes from colorless to red insoluble formazan. The formazan is reduced (gains electrons)

56

What is Brownian motion?

Microbe collisions with water molecules.

Microbes vibrate in place, not swim

57

Sketch the three domains of life, include supergroups, and prokaryotes and eukaryotes

58

What is the name of the bacteria that grows between 50 degrees and 60 degrees C?

Thermophiles

59

What is the Capsule Stain Technique?

Sheep serum, congo red, slide, Maneval stain, water dry

60

What is phenylethyl alcohol agar, PEA, used for?

To isolate staphylocci and streptococci

61

If you get purple metallic growth in eosin methylene blue, EMB, what is the presumptive ID?

Coliform

62

If you get good growth in eosin methylene blue, EMB, what is the presumptive ID?

Gram negative

63

What is the Gram Stain Technique?

Heat fix

Crystal Violet

Water

Iodine

Water

Alcohol

Safranin

Water

Blot

64

Methyl Red MR meaning and purpose?

Detects acid fermentation

65

What is the pH range does phenol red indicate?

Yellow below pH 6.8 Pink above pH 7.4 Red between pH 6.8-7.4

66

What is a antiseptic?

A germicide for use on living tissue.

67

Which bacteria is examined for motility?

Enterobacteriacease

68

Mannitol Salt Agar meaning?

Poor growth or No growth, inhibited by NaCl, not Staph

Good growth, not inhibited by NaCl, Staph

Yellow growth, ferments acid from mannitol, Staph aureus

Red groth, does not ferment mannitol, Staph other than S. aureus

69

What is the dimetral field of view size for a microscope with a 10X occular lens and 4X, 10X, 40X, and 100X objective lenses?

70

What is a denitrifier? Think Nitrate Reduction Test chemistry.

Something that reduces NO3 all the way to N2.

71

Define disinfection

Killing pathogens but not endospores

72

MacConkey agar uses neural red dye. At what pH does it indicate?

0-6.8 pH. Organisms that ferment lower the pH.

73

If you get purple metallic growth in eosin methylene blue, EMB, what is the presumptive ID?

Coliform

74

What does MacConkey agar contain?

Lactose, bile salts, neural red, and crystal violet.

75

What does MacConkey agar contain?

Lactose, bile salts, neural red, and crystal violet.

76

Colagulase and clumping factor test meaning?

Sheilds bacteria from phagocytosis.

77

What does the GasPak Anaerobic System do?

Creates anaerobic, microaerophilic, or CO2 enriched conditions

78

What is a positive result for the Use-Dilution Test?

A positive result will be the surviving bacteria will make the broth turbid, indicating the germicide did not kill the bacteria.

79

Which have turbidity, sediment, and pellicle shown?

the first two turbidity, second two sediment, and the last pellicles 

80

Immunodetective BioKit

81

Blood typing meaning

82

Define sterilization

the complete elimination of bacteria

83

Voges-Proskauer meaning?

84

What is the application for wet mounts and hanging drop technique?

To observe cellular motility

85

 Casein Hydrolysis (Casease Test)?

Clearing around organism, casease is present, +

No clearning, casease is absent, -

Casease is an enzyme to hydrolyze milk protein casein

86

SIM, Sulphur reduction, Indole production, Motility, meaning?

Used to identify bacteria producing indol and differentiate enterbacteriaceae.

Sulphur Reduction test: black, H2S present, +

No black, no H2S, -

Indole Production test: red layer, tryptophanase present, +

color unchanged, no tryptophanase, -

Motility test: growth radiating, +

No growth radiating, -

87

What does eosin methylene blue, EMB, contain?

Gelatin, lactose eosin Y and methylene blue

88

What is the name of the bacteria that grows between 50 degrees and 60 degrees C?

Thermophiles

89

Phenylethyl Alcohol Agar PEA meaning?

Selective for Gram +, not differential

Poor growth, inhibited by phenylethyl alcohol, Gr -

Good growth, not inhibited by phenylethyl alcohol, probable, Staph, Strep, Enterococcus, or Lactococcus

90

Phenylalanine Deaminase Test meaning?

Removal of amino group from phenylalanine.

No color change, phenylalanine deaminase is absent, -

Green, phenylalanine deaminase is present, +

91

What does enterobacteriacease do to nitrate?

A one step reduction from nitrate to nitrite.

92

What test looks for hemolysins?

Blood agar

93

What is a positive motility test result?

Red diffuse growth radiating outward from the stab line.

94

What is the name of the chemical germicide lab?

The Use-Dilution Test

95

Name the parts of the microscope

96

Calculate dilutions

10-1, 10-2, 10-3

97

What is the simple stain technique?

Heat fix

Methylene Blue

Water

Blot

98

What is the name of the bacteria that grows between 20 degrees and 45 degrees C.?

Mesophiles

99

What organisms does the Use-Dilution Test used on?

In class, Staph epidermidis and E. coli

100

What is incomplete lysis?

Alpha-hemolysis, greenish-black zone around colonies.

101

In the Streak Plate Methods of Isolation, what is the purpose of the expereiment?

Isolating individual organisms from a mixed culture

102

What is the purpose of the Use-Dilution Test?

Test the effectiveness of germicides against bacteria.

103

What does deaminization mean?

Breaks amino acids becomes more basic, raises pH, making the broth pink.

104

What is hemolysis?

Lysis of RBC, turns blood agar clear around beta-hemolysis microbes.

105

What does anaerobic respiration do?

Transfer of electrons to an inorganic molecule other than oxygen.

106

What is the end product of fermentation?

Lactic acid, ETOH, CO2

107

What is the name of the nitrate test?

Nitrate reduction

108

What is mannitol salt agar, MSA, used for?

To differentiate staphylococcus aureus from other staphylococcus species. Selective.

109

What is the catalyst in the GasPak?

Palladium

110

What is the name of the tube used to collect gas?

Durham tube

111

Why should Petri dishes be labled on the bottom?

Lids may get seperated

Lid may get rotated to wrong orientation

112

What does MacConkey agar contain?

Lactose, bile salts, neural red, and crystal violet.

A differential medium.

113

Define:

TSIA

EMB

MR-VP

PR

ELISA

PAA

SIM

TSIA - Tripple Sugar Iron Agar

EMB - Eosin Methylene Blue

MR-VP - Methyl Red and Voges-Proskauer

PR - Phenyl red

ELISA - Enzyme-Linked Immunosorbent Assay

PAA - Phenylethyl Alcohol Agar

SIM - Sulphur reduciton Indole production Motility

114

What kind of broth is nitrate broth?

Undefined beef extract, peptone, and potassium nitrate.

115

If you get good growth in MacConkey agar, what is the presumptive ID?

Gram negative

116

Urease test meaning?

Urea is the primary nitrogenous waste in urine and identify H. plyori

117

Oxidase Test meaning?

Identify bacterial containing cytochrome c oxidase.

Purple = + oxidase present

Yellow = - oxidase not present

 

118

If you get good growth in MacConkey agar, what is the presumptive ID? 

If you get red growth, with is the presumptive ID?

Gram negative

Coliform

119

What is tetrazolium salt, TTC, used for?

Looking for red formazan motility positive

120

What microbe does MacConkey agar detect?

Enterobacteriacease to ferment lactose

121

What is the pH range for fermentation?

< pH 6.8 - lactose fermentation

122

What microbe does MacConkey agar detect?

Enterobacteriaceae to ferment lactose

123

Define the temperature ranges for psychrophiles, mesophiles and thermophiles

Psychrophiles 0° - 20° C.

Mesophiles 20° - 45° C.

Thermophiles 50° - 60° C.

124

Motility test meaning?

What are the two chemicals

Red diffues growth radiating from stab, motile, +

No growth away from stabline, nonmotile, -

Tetraxolium salt, TTC and red formazan

125

What does eosin methylene blue, EMB, contain?

Gelatin, lactose, eosin Y and methylene blue

126

In Ex. 1-3, Aseptic Transfer, wht is the purpose of the exercise?

Practice moving growths from a broth culture, an agar slant culture, and a plated culture.

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Draw a 1:1,000 serial dilution