Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Microbioloy > Lab Quiz 3 > Flashcards

Lab Quiz 3 Flashcards

1
Q

purpose of oxidation requirement test

A

determine oxidation requirement of organism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

OR: purpose of sodium throglycollate

A

combine with oxygen to reduce concentration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

OR test: purpose of agar

A

Increase thickness of media to prevent diffusion of oxygen in media

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

OR test: purpose of resazurin

A

indicate presence of oxygen in tube. pink with oxygen, clear without oxygen present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

define and describe obligate aerobe

A
  • organism requires oxygen
  • grown on top of media
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

define and describe microaerophile

A
  • organism requires reduced concentration of oxygen
  • grown above middle of agar
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

define and describe aerotolerant anaerobe

A
  • grows equally well with or without oxygen
  • grown all throughout media
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

define and describe facultative anaerobe

A
  • can grow with or without oxygen but prefers aerobic conditions
  • grow all throughout media but more at the top
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

obligate anaerobe

A
  • can not grow in the presence of oxygen
  • grows at the bottom of media
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

purpose of anaerobic bag test

A

determine if organism can grow in complete anaerobic conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

indicator for bag test

A

methylene blue indicator strip. blue with oxygen and colorless without oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

reaction of anaerobic bag test

A

2H2 + O2 = 2H2O

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Gelatin Hydrolysis test

A
  • substrate: gelatin
  • enzyme: gelatinase
  • product: amino acids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

+ gelatin hydrolysis test

A
  • liquified agar deep after cooling
  • gelatinase produced which broke down gelatin into amino acids and automatically liquified media
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

(-) gelatin hydrolysis test

A
  • solid agar deep after cooling
  • gelatinase not produced and no amino acids form. media remains solid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

why is it necessary to refrigerate gelatin hydrolysis after incubation

A

to prevent gelatin from spontaneously liquifying after incubation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

urease test

A
  • substrate: H2O and Urea
  • enzyme: Urease
  • products: ammonia and CO2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

(+) Urease test

A
  • hot pink broth
  • urease produced and breaks down urea into ammonia and CO2 which increases pH and phenol red changes from yellow to pink
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

(-) urease test

A
  • yellow broth
  • urease not produced. pH remains at 6.8 and phenol red does not change
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

urease indicator

A
  • phenol red pH indicator
  • yellow at 6.8, hot pink >8.4
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

SIM Test: 3 test done

A
  • H2S
  • Indole
  • Motility
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

H2S test

A
  • substrate: cysteine
  • enzyme: cysteine desulfurase
  • products: H2S and pyruvic acid
  • H2S + ferrous sulfate = black ferric sulfide
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

indicator H2S test

A

ferrous sulfate

24
Q

(+) H2S test

A
  • black agar deep
  • cysteine desulfurase produced which creates H2S that combines with ferrous sulfate in media to produce black ferric sulfide
25
Q

(-) test

A
  • yellow agar deep
  • enzyme not produced, no H2S to combine with ferrous sulfate
26
Q

Indole Test

A
  • substrate: tryptophan
  • enzyme: tryotophanase
  • products: indole + Pyruvic acid
27
Q

(+) indole test

A
  • pink layer on top of agar deep
  • organism produces tryptophanase and indole and purivic acid produced. indole detected using Kovacs reagent
28
Q

(-) indole test

A
  • yellow layer on top of agar deep
  • enzyme not produced. tryptophan not hydrolysis to indole. indole reagent remains yellow
29
Q

indole reagent

A
  • kovacs reagent
30
Q

Motility Test

A
  • (+) test: growth diffusion away from stab line of inoculation
  • (-) test: growth restricted to stab line of inoculation
31
Q

Litmus Milk Test Substrates

A

lactose sugar and milk proteins

32
Q

LM test: Acids

A
  • pink opaque media
  • organism uses lactose and acids are produced. pH decreases and litmus turns pink. Opaque since large milk proteins still present
33
Q

LM test: Acids with reduction

A
  • pink opaque media with white band at the bottom of tube
  • organism uses lactose which produces acids. pH decreases and litmus turns pink. excess acid production reduced litmus and turns white. opaque media since milk proteins still present
34
Q

LM test: Alkaline reaction

A
  • purple opaque media
  • organism uses milk proteins which are partially broken down. slight change in consistency and media
35
Q

LM test: Peptonization

A
  • deep purple/blue clear media
  • organism uses milk proteins which are completely hydrolyzed to amino acids. ammonia produced from amino acids which increases pH. litmus turns deep purple/blue. clear media because proteins completely broken down.
36
Q

Litmus Milk Test indicators

A
  • litmus pH and oxidation-reduction indicator
37
Q

(+) Motility Test

A
  • growth dispersion from stab line, cloudy appearance
  • organism is motile and was able to move away from line
38
Q

(-) Motility Test

A
  • broth restricted to stab line
  • organism not motile, growth only seen along stab line
39
Q

indicator used to determine results easier

A
  • tetrazolium red indicator
40
Q

Microbes in food: method used

A
  • standard plate count
41
Q

what is involved in a standard plate count and what does it determine

A
  • serial dilutions of food/liquid sample in sterile water banks
  • determine number of viable bacteria per mL of food sample
42
Q

why is the standard plate count important for food, water, and milk industries

A

it is part of their quality control

43
Q

calculation for organisms per ml or gram

A

number of colonies x final dilution factor

44
Q

why is a plate with 25-250 colonies needed

A

greater than 250 is too many to count. less than 25 will cause unreliable and inaccurate results

45
Q

Define Abstract

A

brief summary of experimentation. provides an over view of your work and the results obtained

46
Q

components of abstract

A
  • background info
  • hypothesis/prediction
  • testing method used
  • results
47
Q

advantage of abstract

A

not having to explain methods used in detail

48
Q

Throat culture: media used

A

5% sheeps blood agar

49
Q

5% sheeps blood agar

A
  • NOT selective media
  • differential media: 3 types of colonies based on hemolysis
50
Q

TC: tests used

A

gram stain and catalase test

51
Q

what test differentiates staphylococcus from streptococcus

A

catalase test

52
Q

define hemolysis

A

destruction of RBCs

53
Q

Aloha hemolysis

A
  • partially lyse RBCs
  • green zone surrounding colonies
54
Q

Beta Hemolysis

A
  • complete lysis of RBCs
  • clear zone surrounding colony
55
Q

Gamma Hemolysis

A
  • do not produce hemolysins
  • red agar surrounding colonies

Microbioloy (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions