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Flashcards in BACTE LAB - AFS Deck (61):
1

Slides must be

new
clean
free from grease
free from fingerprints
unscratched

2

what to write on the frosted end of the slide

laboratory register serial number
order number of the sputum specimen

3

type of pencil to use on unfrosted slides

diamond pencil, left end of the slide

4

what part of the sputum must be taken

yellowish purulent part

5

smear shape

oval

6

smear size

2 cm wide x 3 cm length

7

the smear size corresponds to how many visual fields

150, to be counted in one length

8

if wire loop was used instead of applicator stick, dip it in ___

alcohol washed-sand bottle

9

clean the wire loop in a flask containing ___ before sterilizing in a flame

70% - 90% alcohol with glass beads or sand

10

for accidental contamination with sputum,
hand:

wash with soap and water

11

for accidental contamination with sputum,
cloth:

spray with 5% phenol OR
Soak in disinfectant OR
Autoclave OR
Boil

12

for accidental contamination with sputum,
Surface of container,

wear rubber gloves before handling it

13

for accidental contamination with sputum,
bench of floor

spray with 5% phenol or Lysol

14

How to dry the smears

air dry, not in direct sunlight or over a flame

15

Elements of Quality Smear

Quality of sputum
size of smear
thickness of smear
evenness of smear
staining technique
cleanness of slide

16

What will happen if during fixation the slide was heated for too long or kept stationary

smear will be scorched

17

a good stained smear by ZN method shows ___

strong red AFB, against weak blue background

18

It is not possible to decolorize if _____ are used

cold watery acids

19

To prepare 0.3% Ziehl's carbol fuchsin working solution, mix

10 ml solution A and 90 ml solution B

20

Solution A of Ziehl's carbol fuchsin

Fuchsin Alcoholic Stock Solution

21

Solution A of Ziehl's carbol fuchsin components

3g basic fuchsin
95% alcohol UP to 100 mL

22

Solution A of Ziehl's carbol fuchsin NAME

Aqueous Phenol Solution

23

Solution A of Ziehl's carbol fuchsin components

Phenol crystals 5g
Distilled water up to 90 mL

24

Before adding water, liquefy the phenol crystals by

gentle heating

25

Decolorizing Agent Solutions

Acid-alcohol solution
25% Aqueous Sulfuric Acid Solution

26

Acid-alcohol solution components

95% alcohol --- 970 mL
35% HCl --- 30 mL

27

25% Aqueous Sulfuric Acid Solution components

distilled water 300 ml
conc. sulfuric acid 100 ml

28

0.3% Methylene Blue Counterstaining Solution components

0.3 g methylene blue chloride
distilled water up to 100 mL

29

ZN method requires staining for ___ min

10

30

ZN method requires decolorizing for ___ min

approx 3 min

31

ZN method requires counterstaining for ___ min

not more than 1 min

32

what replaced carbon fuchsin in fluorescence staining

fluorescent dye

33

examples of fluorescent dye

auramine-O
rhodamine
auramine-rhodamine
acridine orange

34

counterstain in fluorescence staining

potassium permanganate

35

describe the decolorize in fluorescence staining

milder

36

with auramine staining, the bacilli appears as (color)

slender bright yellow luminous rods against a dark background

37

identification of mycobacteria with auramine O is due to the

affinity of mycolic acid in the cell walls for fluorochromes

38

light produced by a substance when it is stimulated by another light

fluorescence

39

fluorescence called cold light because

does not come from a hot source like an incandescent light bulb

40

dyes which have the property of absorbing light rays of shorter wavelength and emitting light rays of longer wavelength

fluorescent dye such as auramine O

41

source of light

mercury vapour lamp

42

by meas of ____

only light rays of shorter wave lengths are allowed to emerge

43

rays of ___ wavelengths used for fluorescence microscopy

shorter

44

Heat slides until

Vapor starts to rise and metallic sheen appeara

45

Let the carbol fuchsin staim stand for ---min

10 min

46

Applying time for counterstaining reagent depends on (3)

Quality of specimen
Thickness of smear
Concentration of reagent

47

Poor quality smears can lead to ----

False results

48

If the smear is dark blue, this means that,

The smear is too thick

49

Employed to highlight the stained organisms for easier recognition

Counterstain

50

Examples of fluorescent dye

Auramine-O
Rhodamine
Auramine-rhodamine
Acridine orange

51

Counterstain in fluorescence microscopy

Potassium permanganate

52

Useful to quench background fluorescene

Counterstain (potassium permanganate)

53

Fluorescent dyes are also called

Fluorochromes

54

Principle lf auramine staining

Affinity of mycolic acids for fluorochromes

55

After smearing sputum, let the slide air dry for ---- min

15-20 min

56

T or F
Wet slides can produce aerosols if disturbed

T

57

When is Bsc required

Large volume of positive sputum sx to be handled
In cultures
In drug susceptibility testing

58

Specimens can be discarded by (2)

Burying after chemical disinfection or autoclaving
Safe commercial waste collection services

59

Discard waste in a deep pit of at least --- m depth

1.5

60

Limit the number of slides in each staining batch to a maximum of ---

12

61

Heat slides until

Vapor starts to rise and metallic sheen appears

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