Lab Finals Flashcards
0
Q
3 intracellular nutrients present in chocolate agar
A
- hemoglobin
- hemin (X factor)
- nicotinamide adenine dinucleotide (NAD or V factor)
1
Q
2 bases of blood agar and chocolate agar
A
- trypticase soy agar
- nutrient agar
2
Q
Bacteria inhibited by phenylethyl alcohol (PEA) agar
A
Gram negative bacteria
3
Q
Level of sodium chloride in mannitol salt agar (MSA)
A
7.5% sodium chloride
4
Q
Bacteria that is able to grow on MSA
A
Staphylococcus sp. (+ salt-tolerant strains of Micrococcus and Enterococcus)
5
Q
Carbohydrate in MSA
A
Mannitol
6
Q
Indicator in MSA
A
Phenol red indicator
7
Q
Color of colonies of mannitol fermenters in MSA
A
Yellow
8
Q
Color of phenol red indicator at pH 8.4
A
Red
9
Q
Color of phenol red indicator at pH 6.8
A
Yellow
10
Q
Organisms that grow on Eosin Methylene Blue (EMB) agar
A
Gram negative bacteria
11
Q
Organisms differentiated by EMB agar
A
Lactose fermenters (purple to green metallic sheen) from non-lactose fermenters (colorless)
12
Q
2 dyes in EMB agar that inhibit gram positive bacteria
A
- eosin
- methylene blue
13
Q
Carbohydrate in EMB agar
A
Lactose
14
Q
Color of E. coli in EMB agar
A
Green metallic sheen
15
Q
Organism with fish-eye appearance on EMB agar
A
Enterobacter aerogenes
16
Q
Color of non-lactose fermenters in EMB agar
A
Colorless
17
Q
Organism with green metallic sheen on EMB agar
A
E. coli
18
Q
Organisms that grown on MacConkey (MAC) agar
A
Gram negative bacteria
19
Q
Organisms differentiated by MAC agar
A
Lactose fermenters (pink to red) from non-lactose fermenters (colorless)
20
Q
2 substances in MAC agar that inhibits gram positive bacteria
A
- Bile salts
- crystal violet
21
Q
Carbohydrate source of MAC agar
A
Lactose
22
Q
Organisms that grow on Hektoen Enteric Agar (HEA)
A
Stool pathogens
23
Q
Organisms inhibited by HEA
A
Normal flora coliforms of the lower GI tract
24
2 inhibitors in HEA
Bile salts & citrate
25
3 carbohydrate sources in HEA
- lactose
- sucrose
- salicin
26
Indicator in HEA
Bromthymol blue indicator
27
pH ranges of bromthymol blue
- pH greater than 7.6: blue
- pH 6.0-7.6: green
- pH less than 6.0: yellow
28
H2S indicator in HEA
ferric ammonium citrate with Sodium thiosulfate
29
Color of colonies in HEA if they ferment 1-3 carbohydrates
Orange
30
Color of colonies in HEA is they are non-fermenters of carbohydrates
Green
31
Color of pathogens in HEA
Green colonies with or without black centers
32
Color of normal flora in HEA
Yellow colonies
33
Pathogen that produces yellow colonies in HEA due to sucrose fermentation
Yersinia enterocolitica
34
Organisms that grow in Xylose-Lysine Desoxycholate (XLD)
Stool pathogens
35
Inhibitor in XLD; inhibits gram positive bacteria, E. coli and inhibits swarming of Proteus
Desoxycholate and citrate
36
Indicator in XLD
Phenol red indicator
37
3 carbohydrates in XLD
- Xylose
- sucrose
- dextrose
38
Color of Salmonella on XLD
Red colonies with black centers
39
Color of Citrobacter and Proteus on XLD
Yellow colonies with black centers
40
Organism in XLD that produce red colonies with black centers
Salmonella
41
2 organisms that produce yellow colonies with black centers in XLD
- Proteus
| - Citrobacter
42
Indicator in MAC
Neutral red indicator
43
Color of neutral red indicator in pH 6.8-8.0
Brown
44
Color of neutral red indicator in pH less than 6.8
Pink-red
45
3 inhibitors in SSA
- brilliant green agar
- bile salts
- citrate
46
Carbohydrate source in SSA
Lactose
47
Indicator in SSA
Neutral red indicator
48
Color of lactose fermenters in SSA
Pink-red
49
Color of non-lactose fermenters in SSA
Colorless
50
H2S indicator in SSA
Ferric ammonium citrate with sodium thiosulfate
51
Appearance of Shigella in SSA
Colorless colonies without black centers
52
Appearance of Salmonella in SSA
Colorless colonies with black centers
53
Appearance of normal flora coliforms in SSA
Pink to red colonies
54
A selective medium fot isolation of Salmonella spp. especially S. typhi
Bismuth Sulfite Agar (BSA)
55
2 inhibitors in BSA; inhibits gram positive bacteria, most lactose fermenting intestinal normal flora and Shigellae
- bismuth sulfite
| - brilliant green
56
Appearance of S. typhi colonies in BSA
Black colonies surrounded by a metallic sheen
57
3 Salmonella spp. with colonies that are light green on BSA
- S. gallinarum
- S. choleraesuis
- S. paratyphi
58
Appearance of S. gallinarum, choleraesuis, and paratyphi colonies on BSA
Light green colonies
59
Selective and differential medium for Vibrio spp.
Thiosulfate Citrate Bile salt Sucrose (TCBS) agar
60
4 inhibitors in TCBS; inhibits gram positive cocci, gram negative rods normally present in stool sample
- thiosulfate
- citrate
- bile salt
- increased pH
61
Carbohydrate in TCBS
Sucrose
62
Indicator in TCBS
Bromthymol blue
63
2 Vibrio spp. that produce yellow colonies in TCBS
- V. cholerae
| - V. alginolyticus
64
2 Vibrio spp. that produce blue-green colonies in TCBS
- V. parahaemolyticus
| - V. vulnificus
65
Appearance of colonies by V. cholerae and V. alginolyticus
Yellow
66
Appearance of colonies by V. parahaemolyticus and V. vulnificus
Blue-green colonies
67
Screenig medium used in the identification of Enterobacteriaceae
Triple Sugar Iron (TSI) agar
68
3 carbohydrates in TSI agar
- glucose
- lactose
- sucrose
69
pH indicator of TSI agar
Phenol red
70
H2S indicator of TSI agar
Ferric ammonium citrate with sodium thiosulfate
71
Used to determine the ability of an organism to deaminate lysine, decarboxylate lysine and produce H2S
Lysine Iron Agar (LIA)
72
4 organisms identified using LIA
- Salmonella
- Proteus
- Providencia
- Morganella
73
3 members of the Enterobacteriaceae that are deaminase positive
- Proteus
- Providencia
- Morganella
74
Carbohydrate in LIA
Glucose
75
Amino acid in LIA
Lysine
76
pH indicator in LIA
Bromcresol purple
77
H2S indicator in LIA
Ferric ammonium citrate
78
Medium used for Indol Production Test
Tryptone broth
79
Reagent used in Indol production test
Ehrlich's or Kovac's (paraaminobenzaldehyde)
80
Positive result in Indol production test
Red ring
81
Negative result in Indol production test
Yellow/brown ring
82
Enzyme that oxidizes tryptophan to indol in Indol Production Test
Tryptophanase
83
Medium in Methyl Red test
MRVP (Methyl Red Voges Proskauer) medium
84
Reagent in Methyl Red Test
Methyl red indicator
85
Positive result in Methyl red test
Red solution
86
Negative result in Methyl Red test
Yellow solution
87
Principle of Methyl Red Test
Fermentation of glucose to pyruvic acid which leads to decreased pH and taking of the color of the indicator
88
Medium used in Voges Proskauer test
MRVP medium
89
2 reagents used in Voges Proskauer test
- VP reagent A (alpha naphthol in absolute methyl alcohol)
| - VP reagent B (KOH with creatine)
90
Positive result of Voges Proskauer test
Pink to red color
91
Negative result of Voges Proskauer test
Yellow color or copper-like
92
Produced in VP test positive results
Acetoin
93
Medium used in Citrate Utilization Test
SCA (Simmons Citrate Agar)
94
Indicator of Citrate Utilization Test
Bromthymol blue
95
Positive result of Citrate Utilization Test
Prussian blue color
96
Negative result of Citrate Utilization Test
Green color
97
Medium used for Urease Test
Urea broth
98
Indicator in Urease test
Phenol red
99
Positive result in Urease test
Pink-red
100
Negatvie result in Urease test
No color change
101
Medium for Sulfide Indol Motility (SIM) medium
SIM (Sulfide Indol Motility) medium
102
Reagent for SIM medium
Ehrlich's or Kovac's
103
Signified by the red ring on the surface of the SIM medium
Indol production
104
Carbohydrate in BSA
Glucose
104
H2S indicator in XLD
Ferric ammonium citrate with sodium thiosulfate
