BACTERIOLOGY SIMLAB

Question 1

most commonly used stain in the clinical microbiology laboatory

Answer 1

Gram Stain

Question 2

Procedure of Gram Stain

Answer 2

Crystal Violet - 60 secs
Gram’s Iodine - 60 secs
Acetone Alcohol - 30 secs
Safranin - 60 secs

Question 3

Color of gram-positive bacteria

Answer 3

violet/blue

Question 4

Color of gram-negative bacteria

Answer 4

red/pink

Question 5

What are gram-positive cocci

Answer 5

Staphylococcus
Streptococcus
Lactococcus
Viridans streptococcus
Enterococcus

Question 6

What are gram-negative cocci

Answer 6

Neisseria
Veillonella
Moraxella

Question 7

Gram-positive bacilli

Answer 7

Mycobacterium
Corynebacterium
Clostridium
Bacillus
Erysipelothrix
Lactobacilli
Listeria

Question 8

Gram-negative bacilli

Answer 8

Escherichia
Klebsiella
Enterobacter
Serratia
Hafnia
Yersinia
Pseudomonas
Proteus
Morganella
Shigella
Salmonella

Question 9

used to differentiate acid-fast organisms such as mycobacteria by staining their mycolic acid

Answer 9

Acid Fast Stain

Question 10

Procedure of Acid Fast Stain

Answer 10

Carbolfuchsin - 10-15 mins
Heat
Acid Alcohol - 30 seconds
Methylene Blue - 60 seconds

Question 11

Color of Acid Fast Bacteria (AFB)

Answer 11

Red/Pink

Question 12

Color of Non - Acid Fast Bacteria

Answer 12

Blue/Violet

Question 13

Give an example of Acid Fast Organism

Answer 13

Mycobacterium
Isospora
Cryptosporidium
Nocardia

Question 14

Give an example of Non-Acid Fast Organism

Answer 14

Chlamydia
Rickettsia
Ureaplasma
Mycoplasma
Spirochetes

Question 15

Bartlett’s Criteria

Answer 15

> 25 PMNs and <10 Epithelial Cells

Question 16

Stain for spore-forming bacteria

Answer 16

Schaeffer-Fulton

Question 17

what is the interpretation of +n

Answer 17

1-9 AFB seen in 100 OIF

Question 18

what is the interpretation of +1

Answer 18

10-99 AFB seen in 100 OIF

Question 19

what is the interpretation of +2

Answer 19

1-10 AFB/OIF in at least 50 fields

Question 20

what is the interpretation of +3

Answer 20

> 10 AFB/OIF in at least 20 fields

Question 21

Bacteria that are Rapid Lactose Fermenters (RLF)

Answer 21

Escherichia
Klebsiella
Enterobacter

Question 22

Bacteria that are Late Lactose Fermenters (LLF)

Answer 22

Serratia
Hafnia
Yersinia

Question 23

Bacteria that are Non-Lactose Fermenters (NLF)

Answer 23

Pseudomonas
Proteus
Morganella
Shigella
Salmonella

Question 24

what is the interpretation of O

Answer 24

No AFB seen in 300 oil immersion field (OIF)

Question 25

IMViC Reaction of Escherichia

Answer 25

+ + - -

Question 26

IMViC Reaction of Klebsiella

Answer 26

- - + +

Question 27

IMViC Reaction of Enterobacter

Answer 27

- - + +

Question 28

What does the PYR test detect?

Answer 28

L-pyrrolidonyl arylamidase.

Question 29

What is the function of endospores in bacteria?

Answer 29

Structure resistant to heat, cold, drying, and chemical agents; contains calcium dipicolinic acid.

Question 30

What is the indicator for autoclave sterilization?

Answer 30

Bacillus stearothermophilus

Question 31

What is the indicator for oven sterilization?

Answer 31

Bacillus subtilis var niger

Question 32

Name a group of bacteria that are non-motile.

Answer 32

Shigella Klebsiella Yersinia pestis

Question 33

Which bacteria are routinely screened for in a stool specimen?

Answer 33

Salmonella Shigella Campylobacter

Question 34

What is the purpose of the Acid Fast Stain?

Answer 34

To identify organisms with mycolic acid / hydroxymethoxy acid in their cell walls

Question 35

What is the purpose of enrichment media?

Answer 35

For enhanced growth of organisms.

Question 36

What is the purpose of enriched media?

Answer 36

For fastidious organisms

Question 37

Name an inhibitor for gram-positive organisms.

Answer 37

Crystal violet and sodium desoxycholate.

Question 38

Name an inhibitor for gram-negative organisms.

Answer 38

Sodium azide, potassium tellurite

Question 39

What is the purpose of the optochin test?

Answer 39

Identification of Streptococcus pneumoniae.

Question 40

What is the indicator/reagent used in the coagulase test?

Answer 40

Rabbit plasma.

Question 41

What does the DNAse test detect?

Answer 41

Deoxyribonuclease activity.

Question 42

What does the CAMP test differentiate?

Answer 42

Group B from Group A Streptococcus.

Question 43

Detects Ability to split indole from tryptophan due to the presence of tryptophanase.

Answer 43

Indole Test

Question 44

What is an indole test reagent?

Answer 44

Kovac’s Reagent: P-dimethylamino benzaldehyde

Question 45

Detects acid Ph which indicates glucose fermentation

Answer 45

Methyl Red Test

Question 46

What is Vogues-Proskauer Test Principle

Answer 46

Detects production of acetylmethyl carbinol (acetoin)

Question 47

What is Vogues-Proskauer Test Reagent?

Answer 47

Alpha-naphthol 40% KOH (Barrit’s reagent)

Question 48

What is the Citrate Test Principle?

Answer 48

To determine if an organism can utilized citrate as the sole carbon source

Question 49

What is the Urease Test Principle?

Answer 49

To determine if an organism can hydrolyze of urea

Question 50

What are the Indole-positive bacteria?

Answer 50

PECK ME Pro Pls Providencia Edwardsiella Citrobacter Klebsiella oxytoca Morganella Escherichia Proteus Plesiomonas

Question 51

What are the Vogues-Proskauer-positive bacteria?

Answer 51

KESHa Klebsiella pneumoniae Enterobacter Serratia Hafnia S.aureus

Question 52

What are the Citrate-positive bacteria?

Answer 52

PECKS Pseudomonas Enterobacter Citrobacter Klebsiella Serratia Marcescens

Question 53

Used for presumptive identification of Gram-negative enteric bacteria used to test a microorganism's ability to ferment sugars and produce hydrogen sulfide.

Answer 53

Triple Sugar Iron Agar

Question 54

A/A, H2S -, Gas +

Answer 54

Escherichia Klebsiella Enterobacter

Question 55

K/A, w/ Gas , H2S +

Answer 55

Salmonella Proteus Arizonae Citrobacter Edwardsiella tarda

Question 56

K/A, w/ Gas , H2S -

Answer 56

Providencia Morganella Shigella

Question 57

K/K, H2S -

Answer 57

Pseudomonas Burkholderia

Question 58

ONPG Test Principle

Answer 58

To determine the ability of an organism to produce beta-galactosidase Beta galactosidase converts ONPG to ortho-nitrophenol