Brainscape's Knowledge GenomeTM

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


See full index

Microbiology- Drover > Exam 1: Ch. 4, 9 Videos on Own > Flashcards

Exam 1: Ch. 4, 9 Videos on Own Flashcards

Ch. 4: Microscopy, Staining, and Classification Ch. 9: Physical Methods of Microbial Control

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

What is the shortest distance between two points on a specimen that can still be distinguished as separate entities?

A

resolution

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

What is the ability of a lens to separate or distinguish small objects that are closer together?

A

resolution

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

What is the differences in intensity b/w two objects, or b/w object and background?

A

contrast

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

What does staining a specimen do?

A

increases contrast and resolution by coloring specimens with strains/dyes

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

What is the importance of heating up a slide before staining?

A

smear slide with specimen–> then heat slide to ADHERE specimen to slide–> then stain

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

What is a simple stain?

A

a single color added to slide and tries to stain every organism on slide to make them standout

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

What are differential stains?

A

used to distinguish one organism from another organism on the same slide

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

What simple stain stains purple?

A

crystal violet

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

What color does the simple stain safranin stain?

A

magenta/red

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

What color does the simple stain methylene blue stain?

A

blue

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

What simple stain stains green?

A

malachite green

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

What color does the simple stain Carbol fuchsin stain?

A

red

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

What are the three Differential Stains we need to know?

A
  1. Gram Stain
  2. Acid-Fast Stain
  3. Endospore Stain
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the steps of the Gram Stain?

A
  1. crystal violet primary stain
  2. Decolorize (alcohol)–> purple is washed from Gram(-) cell b/c walls are thiner
  3. Counterstain = safranin; Gram (-) cells take on magenta/red color
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the results from a Gram Stain?

A
  • Gram (+) cells = purple

- Gram (-) cells = magenta.red

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

What group of bacteria does not have a typical peptidoglycan cell wall, but instead of a high waxy mycolic acid content?

A

Mycobacteria

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

What does a mycobacteria contain in their cell wall that makes them resistant to decolorization by acids during staining procedures, like the Gram stain ?

A

a waxy mycolic acid content

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

What are Mycobacteria referred to as?

A

Acid-Fast Bacteria

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

What are the steps for an Acid-Fast Stain?

A
  1. carbol fuchsin primary stain (red)
  2. Decolorize (alcohol); acid-fast retain red color b/c acid cannot penetrate waxy wall
  3. Counterstain (methylene blue)–stains only bleached, non-acid-fast cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the results of an Acid-Fast Stain?

A
  • Acid-fast cells/mycobacterium = red

- Non-Acid-fast cells = blue (includes human cells and tissue)

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

What are the steps for an Endospore Stain?

A
  1. Malachite green primary stain (need heat)
  2. Decolorize (water)
  3. Counterstain (safranin)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the results of an Endospore Stain?

A
  • Endospores = green

- Vegetative/living cells = magenta/red

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

What do we call a series of paired statements where only one of two “either/or” choices applies to any particular organism?

A

Taxonomic Keys/ Dichotomous Keys

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

What is the removal or destruction of ALL microbes, including viruses and bacterial endospores, in or on an object?

A

sterilization

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

What is an environment or procedure that is free of contamination of pathogens?

A

aseptic

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

What is a use of physical or chemical agents known as disinfectants to inhibit or destroy microorganisms?

A

disinfection

DOES NOT guarantee that ALL pathogens are eliminated

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

What is it called when a chemical is used on skin or other tissue?
What is the chemical called?

A

antisepsis

antiseptic

28
Q

What is the removal of microbes from a surface by scrubbing?

A

degerming

29
Q

What is the process of disinfecting places and utensils used by the public to reduce the number of pathogenic microbes to meet accepted health standards?

A

sanitizaiton

30
Q

What is the use of heat to kill pathogens and reduce the number of spoilage microorganisms in food and beverages?

A

pasteurization

31
Q

What are the suffixes used to indicate that a chemical or physcial agent INHIBITS microbial metabolism and growth?

A

-stasis/ - static

have NOT killed them

32
Q

What suffixes refer to agents that destroy or permanently inactivate a particular type of microbe?

A

-cide/ -cidal

DEATH

33
Q

What is Microbial Death?

A

permanent loss of reproductive ability under ideal env.

34
Q

What is Microbial Death Rate?

A

measurement of efficacy of an antimicrobial agent

“how effective it is”

35
Q

What does a 90% microbial death rate mean?

A

90% efficacy rate means 90% more of the pathogen will die after a given unit of time

36
Q

What are the two main categories for Actions of Antimicrobial Agents?

A
  1. Alteration of cell walls and membranes

2. Damage to proteins and nucleic acids

37
Q

What occurs in the antimicrobial agent strategy of–Alteration of cell walls and membranes?

A
  • Cells burst due to osmotic effects when damaged
  • cellular contents leak out when damaged
  • envelope damage prevents attachment, fatally interrupts viral replication
38
Q

What occurs in the antimicrobial agent strategy of– Damage to proteins and nucleic acids?

A
  • denatured proteins cease to function and cause cellular death
  • can produce fatal mutants or halt protein synthesis
39
Q

What are factors that affect the efficacy of antimicrobial methods?

A
  1. Site to be treated

2. Relative susceptibility of microorganisms

40
Q

Why is “site” to be treated a factor in affecting the efficacy of antimicrobial methods?

A

harsh chemicals and extreme heat cannot be used on humans, animals, and fragile objects

41
Q

Why is relative “susceptibility” of microorganisms a factor in affecting the efficacy of antimicrobial methods?

A

how resistant they are:

  • prions, endospores = most resistant
  • Gram (+) bacteria, enveloped viruses = least resistant
42
Q

Which is more resistant to antimicrobials, Gram (+) or Gram (-) bacteria? Why?

A

Gram (-) bacteria is more resistant b/c they have:

  1. a double phospholipid bilayer
  2. tend to have more R plasmids
43
Q

Which are more resistant, prions/endospores OR Gram (+) bacteria/ enveloped viruses?

A

prions/endospores

44
Q

What are the two kinds of heat related methods for physical methods of microbial control?

A
  1. Moist heat

2. Dry heat

45
Q

T/F. Dry heat is more effective than moist heat.

A

False; moist heat is more effective than dry heat

46
Q

What are the 4 methods of using moist heat for microbial control?

A
  1. boiling
  2. autoclaving
  3. pasteurization
  4. ultrahigh-temperature (UHT) Sterilization
47
Q

What type of cells does boiling kill?

What types of cells can survive boiling?

A

Kills: vegetative cells of bacteria and fungi, protozoan trophozoites, and most viruses

Survives: endospores, prions, protozoan cysts, and some viruses

48
Q

What is critical when it comes to boiling?

A

time

49
Q

What type of microbial control using moist heat, involves pressure being applied, and prevents steam from escaping

A

autoclaving

50
Q

What type of microbial control using moist heat is used for milk, ice cream, yogurt, and fruit juices?

A

pasteurizaiton

51
Q

T/F. Pasteurization is sterilization.

A

FALSE, it is NOT sterilization (not killing everything in the food product, it affects taste of food to)

52
Q

What type of microbial control using most heat passes through superheated steam, then rapid cooling?

A

Ultrahigh-Temperature (UHT) Sterilization

  • treated liquids can be stored at room temp (6-9 months), until opened
53
Q

What is the name of the type of packaging that has been done using Ultrahigh-Temperature (UHT) Sterilization?

A

Aseptic packaging

54
Q

As a microbial control method, what does Dry Heat use and why is it done?

A

hot air and incineration is used for materials that cannot be sterilized with moist heat

55
Q

T/F. Dry heat requires higher temperature for longer time than moist heat

A

true

56
Q

What is the ultimate means of sterilization?

A

incineration (burning/fire)

57
Q

Refrigeration and Freezing–what does it do to microbes?

A

decreases microbial metabolism, growth, and reproduction

58
Q

Refrigeration halts growth of most pathogens, what are the exceptions?

A
  • Listeria

- Yersinia

59
Q

What type of microbial control method involves drying that inhibits growth due to removal of water?

A

dessication (“dehydration”)

60
Q

What type of microbial control method prevents formation of damaging ice crystals and is used for long-term preservation of microbial cultures?

A

Lyophilization (“Freeze drying”)

  • like for MRE’s
61
Q

What type of microbial control method involves passage of fluid through a sieve designed to trap particles and separate them from the fluid?

A

filtration

62
Q

What type of microbial control method involves high concentrations of salt or sugar in food to inhibit growth? How does it work?

A

osmotic pressure

- cells in hypertonic solution of salt or sugar lose water = cell crenates

63
Q

T/F. Bacteria have a greater ability than fungi to survive hypertonic environments?

A

False, fungi have greater ability than bacteria to survive hypertonic environments

64
Q

What type of microbial control method involves electron beams or gamma rays?

A

ionizing radiation (work diff though)

65
Q

Compare what electron beams do vs what gamma rays do in ionizing radiation.

A

Electron beams = effective at killing but do NOT penetrate well

Gamma rays = penetrate well, but require hours to kill microbes; also sterilizes food

66
Q

How is increased shelf life of food achieved? (Ex: strawberries)

A

Ionizing radiation (gamma rays)

67
Q

What type of microbial control method involves UV light? What is it suitable for?

A

non-ionizing radiation;

  • UV light does not penetrate well
  • suitable for disinfecting air, transparent fluids, and surfaces of objects

Microbiology- Drover (17 decks)

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