Brainscape's Knowledge GenomeTM

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


See full index

Microbiology > Practical 1 > Flashcards

Practical 1 Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

what does it mean that microorganisms are ubiquitous

A

found in any environmental condition

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

what is a pure culture

A

culture containing a single unadulterated species

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

what does survival and continued growth of microorganisms require

A

nutrients and a favourable growth environment

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

what is a culture medium

A

soluble low molecular weight substances (derived from enzymatic degredation of complex nutrients)

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

what is agar

A

used for solid media, extract of seaweed, is a complex carbohydrate composed mainly of galactose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

why is agar a good solidfying agent

A

liquid at 100c and solid at 40c

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what percent of agar is needed to have a solid media

A

1.5-1.8 percent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the main advantage to using agar slants in test tubes

A

best for maintaining pure cultures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

whats the purpose of agar deep tubes

A

used for the study of gaseous requirements of microorganisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the purpose of agar plates

A

large surface areas for the isolation and study of microorganisms

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

what is sterilization

A

process of rendering a medium or material free of all forms of life

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

what is the main function of aseptic technique

A

maintaining sterile where necessary and avoid external contamination

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

where can you use broth mediums

A

only in test tubes, never in petri dishes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is a way to maintain aseptic technique in mediums

A

plastic lids in petri plates, metal or plastic caps in test tubes (historically cotton plugs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

how must petri dishes be incubated and why

A

incubated inverted (larger cap down) to prevent condensation from dripping

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is subculturing

A

microorganisms being transferred from one vessel to another

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

what are wire loops made of

A

inert metals such as nichrome or platinum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is the function of an incubator

A

maintains a temperature for the microorganisms that is optimal for their growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is the function of a fridge

A

will slow or stop the growth of most microorganisms to be able to use for example as stock cultures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

how do you transfer microorganisms from a tube to a petri plate

A

flame loop, remove cap, flame neck of tube, collect sample, flame neck of tube, cap, open petri plate, spread sample, lid petri plate, flame loop

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is one of the best ways to get a pure culture from a mixed culture

A

streak plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what is a colony

A

individual macroscopically visible masses of microbial growth on solid medium representing replication of single microorganism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is a streak plate

A

essentially a dilution series on solid media

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is colony morphology

A

visible collection of microorganism cells growing on the surface of solidified media

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

for agar slants what are the terms for abundance of growth

A

none, slight, moderate, large

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

for agar slants what are the terms for optical characteristics

A

opaque, translucent, transparent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

for agar slants what are the form types

A

filiform, echinulate, beaded, effuse, arborescent, rhizoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what is filiform growth

A

continuous threadlike growth with smooth edges

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what is echinulate growth

A

continuous threadlike growth with irregular edges

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what is beaded growth

A

nonconfluent to semiconfluent colonies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what is effuse growth

A

thin spreading growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

what is arborescent growth

A

treelike growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what is rhizoid growth

A

root like growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what are the consistencies for agar slants

A

dry, buttery, mucoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

for agar plates what are the form types

A

circular, irregular, rhizoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

what are the margin types for agar plates

A

entire, lobate, undulate, serrate, filamentous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

what is entire for agar plates

A

sharply defined and even

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

what is lobate for agar plates

A

marked indentations

39
Q

what is undulate in agar plates

A

wavy indentations

40
Q

what is filamentous in agar plates

A

threadlike spreading edge

41
Q

what are the elevation types in agar plates

A

flat, raised, convex, umbonate

42
Q

what is umbonate in agar plates

A

raised with an elevated convex central region

43
Q

who pretty well invented the microscope

A

leeuwenhoek

44
Q

what are the present day microscope magnification capabilities

A

greater than 250,000X

45
Q

what are the two basic types of microscopes

A

light or electron

46
Q

what are the types of light microscopes

A

brightfield, darkfield, phase-contrast, fluorescent

47
Q

what kind of microscope uses uv light

A

fluorescence

48
Q

how do electron microscopes work

A

electron beams and magnets to observe submicroscopic particles

49
Q

what are the essential features of a brightfield microscope

A

2 lens system, tungsten light, specimen appears dark against a bright background, no contrast, good for stained slides not for living cells

50
Q

what are the essential features of a darkfield microscope

A

condenser system modified so specimen isnt directly illuminated, specimen appears bright on a dark background, can observe living cells better than brightfield

51
Q

what are the essential features of phase contrast microscope

A

can observe in unstained state, specimen appears dark against a bright background, light refracts to show structures of organism

52
Q

what are the essential features of a fluorescent microscope

A

see organisms tagged with fluorescent dyes, uv light for illumination, used for antigen-antibody interactions, colour on black background

53
Q

what are the essential features of an electron microscope

A

magnification up to 1 million x, illuminated by beam of electrons, focusing is done by electromagnets instead of optics, scanning for surface images, transmission for thin filaments

54
Q

what is the stage of a microscope

A

fixed platform with opening for light passage, typically mechanical and can be moved horizontally and vertically

55
Q

what is the abbe condenser

A

directly under the stage and has two sets of lenses to collect and concentrate light, also contains an iris diaphragm to regulate the amount of light

56
Q

what is the body tube

A

above the stage and attached to arm of microscope, houses lens system to magnify specimen, body tube is lowered and raised by the adjustment knobs

57
Q

how do you manipulate magnification

A

occular lens and objective lens

58
Q

what is numerical aperture

A

function of the diameter of the objective lens in relation to its focal length

59
Q

the ____ the wavelength the ___ the resolving power

A

the shorter the wavelength the greater the resolving power

60
Q

____ wavelengths for ___ resolution

A

short wavelengths for better resolution

61
Q

what is resolving power dependent on

A

refractive index and wavelength

62
Q

what is the refractive index

A

bending power of light passing through air from the glass slide to the objective lens

63
Q

what is the correct setup for koehler illumination

A

eye and specimen focused, specimen and field stop focused

64
Q

what is the function of koehler illumination

A

illuminate specimen on slide, as light passes through specimen it should be parallel and evenly illuminated–its the best image you can get

65
Q

what does it mean that a substage condenser uses a 2 conjugate plane system

A

if one is at focus the other is completely defocused but completely parallel

66
Q

what are the two parts to a conjugate plane system

A

the first is the light source, aperature stop, objective. the second is field stop, specimen, eyepiece/eye

67
Q

what is the formula for resolution

A

wavelength/2*NA (NA is numerical aperature)

68
Q

what is numerical aperture

A

measure of light gathering ability of a lens

69
Q

what is the refractive index of oil

A

1.5

70
Q

what is the refractive index of air

A

1

71
Q

what is numerical aperture of a dry lens

A

1

72
Q

what is numerical aperture of oil lens

A

1+

73
Q

what is the longest wave length

A

red

74
Q

what is the shortest wavelength

A

violet

75
Q

what is a stain

A

an organic compound containing benzene ring plus a chromophore and an auxochrome group

76
Q

what is the function of chromophore

A

brings colour

77
Q

whats the function of auxophore

A

binds the colour of chromophore to fibers or tissues

78
Q

are acidic stains anionic or cationic

A

anionic

79
Q

what are acidic stains used for

A

gram negative bacteria

80
Q

what are basic stains used for

A

gram positive bacteria

81
Q

whats an example of an acidic stain

A

picric acid, nigrosine, congo red

82
Q

whats an example of a basic stain

A

crystal violet, methylene blue, safranin

83
Q

what are the two basic staining techniques

A

simple or differential

84
Q

why is it bad to have too much bacteria on a slide

A

diminishes the amount of light that is able to pass through

85
Q

why is heat fixation required

A

helps anchor bacteria to slide, and kills bacteria

86
Q

what is streptococcus

A

chain of cocci

87
Q

what is staphlococcus

A

unorganized cluster of cocci

88
Q

what is sarcinia

A

cube of cocci

89
Q

how do you do a positive stain

A

put basic stain on slide for 30 seconds, rise excess dye off

90
Q

how do you do a negative stain

A

no heat fixation needed, nigrosin at one end of slide, bacteria in nigrosin drop, spread dot to other end of slide with another slide at a 45 degree angle

91
Q

how many chemical reagents are needed for differential staining

A

4 chemical reagents

92
Q

what is the strength of differential staining

A

you can differentiate gram negative and gram positive bacteria on the same slide

93
Q

how do you do a differential stain

A

start with heat fixed slide, apply basic stain (crystal violet), wash, grams iodine, wash, alcohol, wash, other basic stain, wash

94
Q

what is the function of grams iodine

A

kills bacteria and increases cells affinity for a stain

Microbiology (6 decks)

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