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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