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Flashcards in Lecture 7 Deck (105)
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1
Q

name a solid culture medium

A

agar plate

2
Q

name a liquid culture medium

A

broth

3
Q

name an alive culture medium

A

host

4
Q

what is a culture medium

A

what the organism is growing on

5
Q

what is culture?

A

the mass of organisms

6
Q

do bacteria form colonies in broth?

A

no, they just make the broth cloudy

7
Q

define inanimate media

A

media that is not alive

8
Q

Give synonym for non-synthetic media

A

complex

9
Q

Define non synthetic media

A

at least one ingredient in the media is not chemically defined

10
Q

what are autotrophs?

A

grow their own food through photosynthesis and/or chemosynthesis

11
Q

what are heterotrophs?

A

organisms which need organic media for food

12
Q

what is another word for hypotrophs?

A

obligate parisites

13
Q

what are hypotrophs?

A

organisms which need something alive on which to grow

14
Q

Give an synonym for complex media

A

non-synthetic media

15
Q

what are facilitative heterotrophs?

A

organisms which can grow on both alive and dead material

16
Q

What is natural media?

A

you take your media directly from the environment

17
Q

is natural media appropriate for laboratory work?

A

no

18
Q

is natural media appropriate for commercial work?

A

yes

19
Q

name 3 examples of natural media

A

Milk
dead branch
soil

20
Q

What are the disadvantages to natural media?

A

not chemically defined
not sterile
not suitable for research

21
Q

what are the advantages to natural media?

A

might be the only media that the organism grows on (such as truffles)

22
Q

Name 2 examples of non synthetic media

A

natural media

infusional hot water extracts (teas)

23
Q

What does BHI stand for?

A

brain heart infusions

24
Q

What type of media is BHI?

A

infusional hot water extract (tea)
non synthetic
inanimate

25
Q

how do you make BHI?

A

boil cow brains and hearts until everything is soluble, then evaporate the liquid, powder the solid that is left behind after evaporation

26
Q

Is BHI sterile?

A

yes once autoclaved

27
Q

is BHI suitable for scientific studies?

A

yes

28
Q

What bacteria can be grown on BHI?

A

Streptococci pneumoniae

29
Q

What are the advantages to BHI?

A

sterile
can be used for clinical isolates
can be used in antibiotics research

30
Q

What are the disadvantages of BHI?

A

some organisms won’t grow on it becuase you cooked it

is not chemically defined

31
Q

What do you use teas for?

A

to isolate clinical pathogens in clinical labs

32
Q

Define synthetic media

A

all chemical components are completely defined and quantified

33
Q

What can you add to media as an organic source of nitrogen?

A

amino acids

34
Q

What can you add to media as an inorganic source of nitrogen?

A

ammonium or potassium nitrate

35
Q

What organism needs nitrogen?

A

staphylococcus aureus

36
Q

What kind of organism needs inorganic nitrogen?

A

autotrophs

37
Q

What are the advantages to synthetic media?

A

chemically defined
sterile
pure culture can be grown

38
Q

What are the disadvantages of synthetic media?

A

not suitable in clinical setting
expensive
not all organisms will grow on it

39
Q

What is the goal of isolation medium?

A

to isolate an organism from its natural environment and grow it on a medium

40
Q

What can you use as an isolation medium for a human pathogen?

A

BHI and sheep’s blood

41
Q

What is the goal of using differentiation media?

A

looking for a specific reaction or a way to tell that a specific organism is present

42
Q

Name examples of differentiation media

A

blood agar plate
mannitol salt agar
macconkey’s agar
eosin methylene blue agar

43
Q

which differentiation media is used to find staphylococcus aureus?

A

blood agar

mannitol salt

44
Q

Which differentiation media is used to find streptococcus pneumoniae?

A

blood agar

45
Q

Which differentiation media is used to find choliforms?

A

macconkey’s agar

eosin methylene blue agar

46
Q

What are the three possible reactions to blood agar called?

A

gamma reaction
beta hemolysis
alpha hemolysis

47
Q

What is a gamma reaction?

A

when there is no change in color of the blood agar media around the colony
no hemolysis
no reaction
nonpathogenic

48
Q

What is beta hemolysis?

A

complete breakdown of the blood in the blood agar medium as shown by a clear area around each colony (where the blood was broken down)
pathogenic

49
Q

What is alpha hemolysis?

A

Partial breakdown of the blood in the blood agar medium as shown by a greenish color around the colony
may or may not be pathogenic

50
Q

What organism shows beta hemolysis?

A

staphylococcus aureus

51
Q

What organism shows alpha hemolysis?

A

streptococcus pneumoniae

52
Q

What organism is used for mannitol salt agar?

A

staphylococcus aureus

53
Q

What is mannitol?

A

a sugar alcohol that staph. aureus can digest

54
Q

What happens when Staph. aureus digests mannitol?

A

produces acid

55
Q

What color does the mannitol salt agar turn for a positive result?

A

yellow

56
Q

What color does mannitol salt agar turn for a negative result?

A

red

57
Q

What is the reactive ingredient in MacConkey’s agar?

A

lactose

58
Q

What does MacConkey’s agar do?

A

isolates choliforms

59
Q

What are choliforms?

A

bacteria in your poop and GI tract

60
Q

What does a positive result on MacConkey’s agar look like?

A

the colony will turn pink

61
Q

What does Eosin methylene blue agar test for?

A

choliforms

62
Q

What does a positive result in eosin methylene blue agar look like?

A

purple colonies

63
Q

Name three selective media

A

Mannitol salt agar
MacConkeys agar
eosin methylene blue agar

64
Q

What is selective media?

A

Favors the growth of a specific organism while inhibiting the growth of others

65
Q

What makes mannitol salt agar selective?

A

high salt concentration

66
Q

What does mannitol salt agar favor and what does it inhibit?

A

favors staphylococcus aureus

inhibits streptococci

67
Q

What makes macconkey’s agar selective?

A

bile which emulsifies lipids

68
Q

What does macconkey’s favor and why?

A

G- bacteria because of their lipo-poly-saccharride outer membrane

69
Q

What makes eosin methylene blue selective?

A

dyes

70
Q

What does EMB favor and what does it inhibit?

A

favors G-

inhibits G+

71
Q

What is enriched media?

A

extra ingredients are added to promote the growth of certain organisms

72
Q

Name some enriched media

A

BHI with sheeps blood
Louenstein jensen
Chocolate agar

73
Q

Enriched BHI is to promote the growth of what?

A

streptococcus pneumoniae

74
Q

louenstein jensen is an enriched media to grow what?

A

Mycobacterium

75
Q

Chocolate agar is an enriched medium to grow what?

A

haemophillus influenzae

neisseria gonorrhea

76
Q

Is BHI with sheeps blood selective? why?

A

no, it doesn’t inhibt the growth of an organism

77
Q

Is BHI with sheeps blood an isolation medium? why?

A

yes, because it isolates strep pneumo from it’s natural environment

78
Q

Is BHI with sheeps blood differential? why?

A

yes because depending on how an organism reacts with the blood you can tell what kind of organism you have

79
Q

Is BHI with sheeps blood enriched? why?

A

yes it is, it is BHI which has been enriched by sheeps blood to better grow strep pneumo

80
Q

Is louenstein jensen an isolation medium?

A

yes

81
Q

Is louenstein jensen a differential medium?

A

no

82
Q

Is louenstein jensen an enriched medium? why?

A

yes, TB won’t grow on BHI alone and it needs the lounestein jensen to grow

83
Q

Is louenstein jensen a selective medium? why?

A

yes, it inhibits G+ firmicutes and favors actinobacteria

84
Q

Is chocolate agar an isolation medium?

A

no

85
Q

Is chocolate agar a differential medium?

A

no

86
Q

Is chocolate agar an enriched medium?

A

yes

87
Q

Is chocolate agar a selective medium?

A

no

88
Q

How do you make chocolate agar?

A

heat up blood agar plate to 100 degrees and the hemoglobin will break down turning the blood brown

89
Q

What should you use thayer martin selective agar to grow?

A

neisseria

90
Q

What is VCA?

A

vancomycin
colistin
nystatin

91
Q

what does vancomycin do?

A

inhibits G+ bacteria

92
Q

What does colistin do?

A

inhibits G- rods

93
Q

What does Nystatin do?

A

inhibits yeast

94
Q

What should you use VCA to grow?

A

neisseria

95
Q

Name a liquid medium

A

BHI broth

96
Q

How do you make BHI broth?

A

BHI powder and water

97
Q

What temperature does BHI agar melt at?

A

100 degrees

98
Q

What temperature do you autoclave at?

A

121.5 degrees

99
Q

What temperature is molten agar?

A

45 to 50 degrees

100
Q

At what temperature does BHI agar solidify?

A

40 degrees

101
Q

What is BHI agar?

A

BHI and 1.5% agar

102
Q

What is the difference between a solid medium and a liquifyable solid medium?

A

you cannot remelt a solid medium

103
Q

Name some solid mediums

A

blood agar plate

Silica

104
Q

At what temperature does a blood agar plate become a chocolate agar plate?

A

100 degrees

105
Q

What is hemolysis?

A

the breaking open of red blood cells and the release of hemoglobin into the surrounding fluid