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Flashcards in Lab exam 2 Deck (40)
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1
Q

Antiseptic

A

Chemicals used on living tissues to decrease the number of microorganisms

2
Q

Disinfectant

A

Chemical agents used on inanimate objects to reduce the number of microorganisms on the surface

3
Q

Antibiotic

A

A substance produced by a microorganism that is inhibitory for other microorganisms

4
Q

Plaque

A

After several rounds of infection and release, all the bacteria in the area of the original virus are lysed and clear areas (plaque) form

5
Q

Viruses that infect bacteria are known as

A

Bacteriophage

6
Q

What agar medium is used for antibiotic sensitivity testing?

A

Mueller-Hinton agar plate

7
Q

What does the starch agar plate test for?

A

Presence of enzymes to break down starch into glucose molecules

8
Q

What does the casein (skim milk) agar plate test for?

A

Presence of enzyme to break down casein protein into individual amino acids

9
Q

What does the lipid (spirit blue) agar plate test for?

A

Presence of lipase enzymes to break down lipids into fatty acids

10
Q

What does the phenol red glucose broth test for?

A

Acid and gas production from glucose fermentation

11
Q

What does the phenol red lactose/and phenol red Mannitol broth test for?

A

Acid production from lactose or mannitol fermentation

12
Q

What does the methyl red VP broth test for?

A

Mixed acids from glucose fermentation that lower the pH below 4.5

13
Q

What does the Voges-Proskauer MR-VP broth test for?

A

tests for butanediol production from glucose fermentation

14
Q

What does the oxidase TSA slant test for?

A

Presence of cytochrome c oxidase in some aerobic bacteria

15
Q

What does the catalase TSA slant test for?

A

Presence of catalase enzyme used to break down H2O2

16
Q

What does the citrate slant test for?

A

Use of citrate as the only carbon source for ATP generation

17
Q

What does the nitrate broth test for?

A

Presence of enzyme nitrate reductase for use of nitrate as an alternative electron acceptor in the ETC

18
Q

What does the indole tryptone broth test for?

A

Presence of enzyme tryptophanase which breaks down tryptophan in medium to pyruvate, ammonium, and indole

19
Q

What does the urea broth test for?

A

Presence of enzyme urease which breaks down urea in medium to ammonia

20
Q

What does the TSI agar slant test for?

A

Enzymes to convert sodium thiosulfate to H2S and fermentation of glucose and lactose and sucrose

21
Q

What are the positive and negative results of the phenol red glucose broth?

A
Positive = yellow
Negative = red/pink
22
Q

What are the positive and negative results of the phenol red lactose/mannitol broth?

A
Positive = yellow and cloudy
Negative = red/pink and cloudy
23
Q

What are the positive and negative results of the MR-VP methyl red test?

A
Positive = red
Negative = yellow or orange
24
Q

What are the positive and negative results of the MR-VP Voges-Proskauer test?

A
Positive = red
Negative = yellow
25
Q

What are the positive and negative results of the TSA slant oxidase test?

A
Positive = purple
Negative = clear or yellow
26
Q

What are the positive and negative results of the TSA slant catalase test?

A
Positive = bubbling 
Negative = no bubbles
27
Q

What are the positive and negative results of the citrate slant?

A
Positive = deep blue
Negative = dark green
28
Q

What are the positive and negative results of the nitrate broth?

A
Positive = bright orange
Negative = cloudy or no change
29
Q

What are the positive and negative results of the tryptone broth indole test?

A
Positive = bright pink top layer
Negative = yellow or greenish layer
30
Q

What are the positive and negative results of the urea broth?

A
Positive = bright pink 
Negative = light orange
31
Q

What are the positive and negative results of the triple sugar iron (TSI) agar slant?

A
Positive = blackening for H2S production
Negative = no blackening for H2S
32
Q

What are the positive and negative results of the starch hydrolysis agar plate?

A
Positive = clear zone around area of growth
Negative = no zone around area of growth
33
Q

What are the positive and negative results of the casein hydrolysis agar plate?

A
Positive = clear zone around area of growth 
Negative = no zone around area of growth
34
Q

What are the positive and negative results of the lipid hydrolysis spirit blue agar plate?

A
Positive = deep blue zone around area of growth 
Negative = clear or light blue zone around area of growth
35
Q

What are the positive and negative results of the lipid hydrolysis (spirit blue) agar plate test?

A
positive = deep blue zone around area of growth
negative = clear or light blue zone around area of growth
36
Q

What are the positive and negative results of the starch hydrolysis agar plate?

A
positive = clear zone around area of growth
negative = no zone around area of growth
37
Q

What are the positive and negative results of the casein hydrolysis agar plate?

A
positive = clear zone around area of growth
negative = no zone around area of growth
38
Q

A greater or bigger diameter of zone of inhibition corresponds to what?

A

increasing sensitivity of bacteria to antibiotics

39
Q

Bacteria that are resistant to antibiotics correspond to what?

A

a lower or smaller diameter of zone of inhibition; which compared to intermediate or sensitive bacteria that have large diameters

40
Q

Viruses are what? Incapable of what?

A

Obligate intracellular parasites,

Incapable of independent replication