Brainscape's Knowledge GenomeTM

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


See full index

Bacte LAB > Activity 8-12 > Flashcards

Activity 8-12 Flashcards

1
Q

-polysaccharide derived from red algae is added to solidify nutrient liquid media

-allowed specimen to be spread across the surface of the medium and grown to produce single colonies, isolating the various microorganisms which are present

-suited as a solidifying agent because it will not melt until the medium is heated to near boiling(95degree C- 100 degree C) but will remain melted untilcooled (42 degree C)- agar solidifies at this temperature

-allow strict control of the growth factors

A

Agar

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

Culture media are sterilized by?

A

Autoclaving

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

Media that contains heat labile components like G, A, U, S, B ARE NOT AUTOCLAVE. What are they?

A

glucose, antibiotics, urea, serum, blood

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

Once the media is prepared, it is held at ________ degrees in the refrigerator for ________ weeks. How many degrees and weeks?

A

4-5°C;1-2weeks

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

For Blood Agar, cool melted agar base to about 45-50°C before adding whole blood (5ml/100ml of blood agar base)

A

Fact

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

Mix blood with agar by rotating media and making figures of 8, w/o producing bubbles

A

Fact

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

For Chocolate Agar, cool agar base to about 50- 60 degreeC before adding whole blood.

A

Fact

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

What will lyse RBC giving the medium a chocolate brown color?

A

High Temperature

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

the lysis releases intracellular nutrients such as ________ and ____________?

A

hemin (X Factor); coenzyme Nicotinamide Adenine Dinucleotide (NAD or V Factor)

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

What will inactivates the enzymes NADases that hydrolyze “V Factor”

A

Heat

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

CONTROL of microorganisms is essential in order to prevent the transmission of diseases and infection, stop decomposition and spoilage, and PREVENT UNWANTED MICROBIAL CONTAMINATION microorganisms are controlled by means of physical and chemical agents

A

Autoclave

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

Physical Agents?

A

High or low temperature, Dessication, Osmotic Pressure, Radiation, Filtration

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

chemical agents?

A

disinfectants, atibiotics, chemoterapeutic antimicrobial chemicals

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

Fact

A

Microorganisms have a minimum, an
optimum, and a maximum temperature for growth

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

Temperatures below the minimum usually have ______ action on microorganisms

A

Static

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

they inhibit microbial growth by slowing down metabolism but do not necessarily kill the organism

A

Static Action

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

Temperatures above the maximum usually have __________ since they denature microbial enzymes and other proteins.

A

Cidal action

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

is a very common and effective way of controlling microorganisms

A

Temperature

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

vegetative microorganisms can generally be killed at _________ with moist heat.

A

50-70°C

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

Fact

A

Bacterial endospores are very resistant to heat and extended exposure to much higher temperature is necessary for their destruction

high temperature may be applied as either moist heat or dry heat

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

is generally more effective than dry heat because of its ability to penetrate microbial cells

kills organism by denaturing their
protein (causes proteins and enzymes to lose their three dimensional functional shape).

it also may help lipids in cytoplasmic membranes

A

Moist Heat

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

Autoclaving employs?

A

Steam under pressure

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

During autoclaving, the materials to be sterilized are placed under ___ pounds per square inch of pressure in a pressure cooker type of apparatus.

A

15; raised to 121°C; 15 minutes

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

temperature to sufficiently kill bacterial endospores

A

121°C

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

is cidal for both vegetative organisms and endospores

is the most common method of sterilization for materials not damaged by heat.

A

Autoclaving

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

(Parts of the pressure cooker)

holds the chamber

A

Body

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

(Parts of the pressure cooker)

where apparatus or media to be sterilized is places

A

Chamber

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

measure the pressure in the chamber

A

Pressure Gauge

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

regulates the pressure inside the chamber

A

Pressure Relief Valve

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

an exhaust for steam when pressure is reduced

A

Air Evacuation Valve

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

gives simultaneous readings for pressure and temperature

A

Pressure Temperature Thermometer

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

fasten the lid orcover to the body

A

Wing nut compression screews

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

the streak plate technique is used to spread

million of cells over the surface of a solid medium so that some individual cells are deposited at distance from all others.

  • these cells grow and reproduce, forming an isolated colony.
A

Isolation Techniques

34
Q

Example of streaking method of isolation:

A
  • Four way streak method
  • Urine culture streak method
  • Three way streak method
  • S- Streak method
35
Q

For incubation, what are the degrees for it and until what time?

A

place the plate in 35-37 degree celcius incubator for 18-24 hrs

36
Q

T Streak Method

A
  • draw T on the bottom of petri dish
  • aseptic technique is observed
  • the loop should be parallel to agar surface to prevent digging into the agar
  • streak about half of agar plate

-make one streak into the inoculated portion of the plate. finish b streaking about 1/4 of uninoculated plate.

37
Q

Pour Plate Technique

A

One in which a small amount of inoculum from broth cultures/liquid specimen is added by pipette into a molten, cooled agar medium (45-50 degree C)

  • pour plates allow microorganisms to grow broth on the surface within the medium.
  • most of the colonies grow within the medium and are small in size; few that grow on the surface are oyn the same size and appearance as those on a streak plate.
38
Q

tube media maybe in form of _______,_____,______ depending on the purpose of the inoculation and the type of medium used, inoculating loop or wire loop may be used.

A

solid agar slants, semi solids or broths,

39
Q

place the loop at the base of the slant surface and draw it up the agar surface while moving it from side to side.

A

Agar slants

40
Q

insert the inoculating needle and stab it in the center of the agar tube to the bottom. draw the needle out carefully, keeping it straight.

A

Agar butts

41
Q

Used to test large volume of liquid samples, including water and filterable beverages

A

Membrane Filtration Method

42
Q

used as enrichments and general cultivation

A

Innoculation of Broth Media

43
Q

contains two or more bacterial species that are known and can be easily separated based on cultural or biochemical characteristics.

A

Mixed Culture

44
Q

provides a means for
maintaining adequate nutrition for the organisms so they can continue to survive

A

Culturing Techniques

45
Q

Culturing procedures

A

Isolation techniques

46
Q

is a colony that is not touching any other colonies and assumed to be a pure culture. these colonies are easily accessible for performing staining identification processes.

A

Isolated Colony

47
Q

is a very homogeneous population formed by the progeny of a single bacterium

A

Bacterial Colony

48
Q

Seven macroscopic characteristics of bacterial colonies

A

Size, Shape(Form), Margin, Surface Texture, Pigmentation, Transmitted light/ optical property, & Elevation

49
Q

whenever possible measure colony diameter and express in mm

A

Size

50
Q

Size

A
  • punctiform- to small to measure
  • moderate- 1mm-5mm
  • large- 5-10mm
51
Q

Shape/Form

A

Circular, Irregular, Filamentous, Rhizoid

52
Q

outer edge/periphery of the coloy

A

Margin

53
Q

Margin

A
  • entire- even
  • Undulate/wavy
  • Filamentous
  • Erose/serrated
  • Lobate/Curled
54
Q

Surface Texture

A
  • Rough/coarse
  • smooth/shiny
  • mucoid
  • wrinkled
55
Q

the color as precisely as possible

A

Pigmentation

56
Q

Transmitted light/ optical property:

A

Transparent, Opaque, Transluscent

57
Q

the light passes to the colony; clear

A

Transparent

58
Q

if the light does not pass through
the colony

A

Opaque

59
Q

if the light can pass in a diffuse manner so that a colony is illuminated but objects at the other side cannot be seen directly

A

Translucent

60
Q

Elevation

A
  • flat raised
  • convex/dome shape
  • umbonate
61
Q

enriched, general supportive and

differential medium used to grow a variety of fastidious microorganism such as Streptococcus.

  • can function as differential media because it can demonstrate different types of hemolysis such as:
    Beta, Gamma(Non), Alpha hemolysis
A

Blood Agar

62
Q

complete lysis of RBC by streptolysin O and streptolysin S enzymes; which produces clear halo around the colonies

A

Beta hemolysis

63
Q

incomplete lysis of rbc resulting in breakdown of hemoglobin, which produces greenish halo around bacterial colonies

A

Alpha Hemolysis

64
Q

no lysis of rbc; no
significant change in color of the agar surrounding the colonies

A

Gamma (Non) Hemolysis

65
Q

provide serum ingredients and
erythrocytes which would allow differentation of microorganisms growing based on their
hemolytic reactions.

A

Blood

66
Q

-selective media

-grows only staphylococcus bacteria

-7.5% salt is inhibitory to most other bacteria

  • it is a nutritive medium due to its contents of peptones and beef extract, which supply essential growth factors such as nitrogen, carbon, sulfur and trace nutrients
  • also a differential media used to distinguish between Staphylococcus aureus and other Staphylococcus spp.
A

Mannitol Salt Agar (MSA)

67
Q

Fact

A

mannitol fermenation with subsequent acid production by S. aureus is indicated by a change in the color of the phenol red indicator to yellow

68
Q

the name of the enzyme found in
most bacteria which initiates the breakdown of hydrogen peroxide (H202) into water (H20) and free oxygen (02)

A

Catalase

69
Q

Fact

A

Most bacteria are catalase (+)

70
Q

Catalase (-)

certain genera that dont carry out aerobic respiration, such as

A

Streptococcus, Lactobacillus, and Clostridium

71
Q

The catalase test differentiates the

A

Staphylococci
Streptococci

72
Q

Streptococci catalase ?

A

-

73
Q

Staphylococci catalase ?

A

+

74
Q

Oxygen bubbling in catalase test?

A

Positive

75
Q

Little to no bubbling in the catalase test?

A

Negative

76
Q

Little to No bubbling in catalase test

A

Negative

77
Q

Little to No bubbling in catalase test

A

Negative

78
Q

Fact

A

Do not pick colonies from BAP for catalase test because RBC contains catalase. This may lead to false positive reaction.

79
Q
  • used to differentiate Staph aureus (coagulase positive) from coagulase negative staphylococci.
  • S. aureus produces two forms of coagulase:
    •bound coagulase
    •free coagulase
A

Coagulase Test

80
Q

is bound to the bacterial cell wall and directly reacts with fibrinogen.

A

Bound coagulase or clumping factor

81
Q

macrocopic clumping in 10-15 secs

A

Positive

82
Q

No clumping

A

Negative

Bacte LAB (1 decks)

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