METHODS OF BACTERIAL IDENTIFICATION

Question 1

Hanging drop technique is a test for:

Answer 1

Motility

Question 2

Used to detect Treponema pallidum in material from primary or secondary syphilitic lesions or other spirochetes such as Leptospira:

Answer 2

Darkfield microscope

Question 3

microscope that is useful in unstained specimens:

Answer 3

Phase-contrast microscopy

Question 4

The primary stain of gram stain:

Answer 4

Crystal violet

Question 5

Duration of primary stain:

Answer 5

1 minute

Question 6

Mordant of gram stain:

Answer 6

Gram’s iodine

Question 7

Duration of the mordant:

Answer 7

1 minute

Question 8

Decolorizer of gram stain:

Answer 8

Alcohol-acetone

Question 9

Duration of decolorizer in gram stain:

Answer 9

Quick on and rinse

Question 10

Secondary stain of gram stain:

Answer 10

Safranin

Question 11

Duration o the secondary stain in gram stain:

Answer 11

30 seconds

Question 12

Most critical step in gram staining:

Answer 12

Decolorizing

Question 13

What is the purpose of mordant in gram staining?

Answer 13

Fixes the stain

Question 14

A unique component in bacteria where Acid-fast stain binds to.

Answer 14

Mycolic acid in the cell wall

Question 15

Hot method of acid-fast staining:

Answer 15

Ziehl-Neelsen

Question 16

Cold method of acid-fast staining:

Answer 16

Kinyoun

Question 17

Primary stain of AFP:

Answer 17

Carbol fuchsin

Question 18

Mordant used in cold method AFP:

Answer 18

Phenol

Question 19

Mordant used in Hot method AFP:

Answer 19

Heat

Question 20

Decolorizer of AFP:

Answer 20

Acid-alcohol

Question 21

Secondary stain of AFP:

Answer 21

Methylene blue or Malachite green

Question 22

AFP smear size should be at-least like a thumb size or _____.

Answer 22

2 cm X 3 cm

Question 23

Used to stain mycobacteria; binds to mycolic acid in the organism’s cell wall, staining the bacteria yellow to orange:

Answer 23

Rhodamine-auramine

Question 24

Fluorochrome dye that stains both gram-positive and gram-negative bacteria, living or dead; Binds to the nucleic acid of the cell and fluoresces as a bright orange when a fluorescent microscope is used.

Answer 24

Acridine orange

Question 25

Fluorochrome dye that binds to chitin in fungal cell walls. Fluoresces as a bright apple-green or blue-white, allowing visualization of fungal structures with a fluorescent microscope.

Answer 25

Calcofluor White

Question 26

Traditionally has been used to stain C. diphtheria for observation of metachromatic granules; Also used as a counterstain in acid-fast staining procedures.

Answer 26

Methylene blue

Question 27

Metachromatic granules observed in C. diphtheria when stain when stained with methylene blue:

Answer 27

Babes Ernst Granules

Question 28

Negative stain used to visualize capsules surrounding certain yeasts such as Cryptococcus spp.

Answer 28

India ink

Question 29

The primary stain of Endospore stain:

Answer 29

Malachite green (heated to steaming for about 5 minutes|)

Question 30

Counter stain of Endospore stain:

Answer 30

Safranin

Question 31

Endospores appear _______ within pink-appearing or red-appearing bacterial cells:

Answer 31

Endospores appear GREEN within pink-appearing or red-appearing bacterial cells

Question 32

Endospore stain is also known as:

Answer 32

Schaeffer-Fulton stain/ Wirtz-Conklin stain

Question 33

Use fluorescein-labeled antibodies from antisera produced by injecting animals with whole organisms or complex antigen mixtures.

Answer 33

Immunofluorescent antibody (IF) staining

Question 34

IF staining is most useful in confirming the presence of specific organisms such as _______ or _______ in colonies isolated on culture media.

Answer 34

Bordetella pertussis or Legionella pneumophilia

Question 35

Contains no solidifying agent (Broth, Infusion, Milk)

Answer 35

Liquid culture media

Question 36

Semi-solid culture media contains ____% Agar; Red algae/Gelidium

Answer 36

Semi-solid agar: 0.5-1% Agar

Question 37

Solid Liquefiable culture media contains _____% Agar

Answer 37

2-3% Agar

Question 38

Non-liquifiable culture media:

Answer 38

Chopped meat (Anaerobe) Rice grain (Fungi)

Question 39

__________ is recommended for organisms that cannot grow in cell-free media.

Answer 39

Tissue cell culture

Question 40

Mccoy cell culture comes from:

Answer 40

Mouse cell line

Question 41

Mccoy cell culture is used to isolate:

Answer 41

Chlamydia

Question 42

Vero cell culture comes from:

Answer 42

African green monkey

Question 43

A549 cell culture comes from:

Answer 43

Lung carcinoma

Question 44

Hela cell culture comes from:

Answer 44

Cervical carcinoma

Question 45

Hep-2 cell culture comes from:

Answer 45

Laryngeal carcinoma

Question 46

Supports the growth of non-fastidious organisms. ex: Nutrient agar or broth; trypticase soy agar or broth

Answer 46

Simple/General

Question 47

Select the growth of a particular organism and prevent other organisms through inhibitors.

Answer 47

Selective media

Question 48

Lowenstein Jensen media is a selective medium used to isolate:

Answer 48

Mycobacterium tuberculosis

Question 49

Phenylethyl alcohol media is a selective medium used to isolate:

Answer 49

Gram-positive microorganism

Question 50

Selective media used to isolate Neisseria gonorrhea

Answer 50

Thayer Martin Martin Lewis New york city

Question 51

Culture media that contains nutrient supplements.

Answer 51

Enriched

Question 52

Blood agar plate is an enriched culture media that contains:

Answer 52

5% defibrinated Sheep blood (Horse/Rabbit) Sheep blood is the most preferred!

Question 53

If human blood is used to make blood agar, what type of blood must be used?

Answer 53

Type O blood

Question 54

Can enhance the growth of microorganisms

Answer 54

Enrichment media

Question 55

Alkaline peptone water is an example of an enrichment media that used for:

Answer 55

Vibrio

Question 56

Allow certain types of organisms to grow and differentiate, and inhibit the growth of other organisms.

Answer 56

Selective-Differential

Question 57

Mannitol salt agar is a type of selective-differential media that is used for:

Answer 57

S. aureus and S. epidermidis/saprophyticus - S. aureus forms a yellow halo (red--->yellow) around the colony which indicates mannitol fermentation - Other Staph spp. can grow but remains red

Question 58

Thiosulfate Citrate Bile Salt is a type of selective-differential media that is used for:

Answer 58

Vibrio spp.

Question 59

Provides distinct colonial appearance of microorganisms to know their identification:

Answer 59

Differential media

Question 60

TSI (Triple Sugar Iron) contains 3 sugars. What are these 3 sugars?

Answer 60

Lactose Glucose Sucrose

Question 61

Green zone around colony. May be narrow or wide; Partial lysis of RBCs.

Answer 61

Alpha hemolysis

Question 62

Examples of alpha-hemolytic organisms:

Answer 62

- Streptococcus pneumoniae - Viridans strep - Some enterococci

Question 63

Clear zone around colony. May be narrow or wide; Complete lysis of RBCs

Answer 63

Beta-hemolysis

Question 64

Examples of Beta-hemolytic organisms:

Answer 64

- Group A strep (S. pyogenes) - Group B strep (S. agalactiae) - Listeria monocytogenes

Question 65

No zone of hemolysis; No lysis of RBCs:

Answer 65

Gamma (nonhemolytic)

Question 65

An organism characterized by its "double zone" hemolysis also known as target hemolysis:

Answer 65

Clostridium perfringens - C. perfringens causes Gas gangrene

Question 66

Alpha-prime (a') or wide zone hemolysis is demonstrated by:

Answer 66

Viridans strep

Question 67

To read the hemolytic reaction on a blood agar plate, the plate must be held up to a light source and observed with the lighting ______________.

Answer 67

lighting coming from behind (transmitted light)