Chapter 7 Flashcards

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

Sepsis

A

microbial contamination

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

Asepsis

A

absence of significant contamination

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

biocide/germicide

A

kills microbes

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

bacteriostasis

A

inhibits growth of microbes, but doesn’t kill them

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

After the removal of a bacteriostatic agent, microbial growth _______________.

A

can resume

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

What are three ways that control agents affect microbial cells?

A
  1. Alter membrane permeability 2. Damage proteins 3. Damage nucleic acids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

4 Factors that Influence the Effectiveness of Control Treatment

A
  1. Number of microbes 2. Amount of time exposed to treatment 3. Environment 4. Microbial Characteristics
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Why does the number of microbes affect the effective on control treatment?

A

takes longer to kill them all

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

Examples of Environmental Influences on the effectiveness of control treatments:

A

organic matter, temperature, biofilms

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

What microbial characteristics makes it harder to kill microbes?

A

Being mycobateria, or having endospores

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

Sterilization

A

complete elimination of all living organisms, including endospores

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

Disinfection

A

Killing or removal of pathogens from inanimate objects; typically does not kill spores

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

Antisepsis

A

Killing or removal of pathogens from living tissues; typically does not kill spores

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

Sanitation

A

reduction of microbes on eating and drinking utensils to safe levels

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

4 Types of Physical Control

A

high temperature, low temperature, filtration, radiation

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

_____ heat is more effective than ___ heat

A

Moist; dry

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

Killing spores and thermophiles usually requires _____ heat and _____ temperature.

A

high; high

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

How does an autoclave kill microbes?

A

Denatures proteins

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

Commercial Sterilization

A

enough heat to kill Clostridium botulinum endospores; not completely sterile

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

Botulism

A

Clostridium botulinum; rare but serious paralytic disease caused by a nerve toxin

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

Pasteurization

A

reduces spoilage organisms and pathogens

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

What is a common method of pasteurization in the US?

A

HTST (High Temperature Short Time) 72C for 15 sec

23
Q

What is a common method of pasteurization in Europe?

A

UHT (Ultra High Temperature) 140C for

24
Q

Are these all equivalent treatments?
63C for 30 min
72C for 15 sec
90C for 0.5 sec

A

Yes

25
Q

Ultra-High Pasteurization

A

138 C for at least 2 sec; done before or after packaging; extended shelf life under refrigerated conditions

26
Q

3 Types of Dry Heat Sterilization

A

Flaming, Incineration, Hot-air sterilization

27
Q

Low temperatures ______ _______ and preserve strains -stasis

A

slow down growth

28
Q

Your refrigerator is what temp?

A

4-8C

29
Q

Lyophilization

A

freeze drying

30
Q

membrane filtration

A

physical removal of microbes from solutions

31
Q

2 common pore sizes for filtration:

A

0.22 micrometers and 0.45 micrometers

32
Q

UV light has poor penetration. It is used for _______ sterilization

A

surface

33
Q

Microwaves kill by heat, but _____ antimicrobial

A

aren’t

34
Q

High pressure ___________ __________

A

denatures proteins

35
Q

Dessication

A

prevents metabolism by removing water

36
Q

Osmotic pressure causes _________

A

plasmolysis

37
Q

Phenols and Phenolics cause ________. In other words, they disrupt the _______ _________.

A

leakage; plasma membrane

38
Q

phenols are useful against _______________

A

mycobacteria

39
Q

Iodine

A

alters protein synthesis and membranes

40
Q

Iodine is used for:

A

skin disinfection

41
Q

Chlorine

A

oxidizing agents that inhibit enzyme activity

42
Q

Chlorine is used for:

A

disinfection of water

43
Q

3 main parts to ethanol

A
  1. denatures proteins
  2. dissolves lipids
  3. requires water
44
Q

Heavy metals have oligodynamic properties meaning:

A

They denature proteins

45
Q

Aldehydes ________ proteins by ____-_________ with functional groups. They damage nucleic acids.

A

inactivate; cross-linking

46
Q

2 Uses of Formaldehyde

A
  1. Disinfectant that kills bacteria and fungi

2. Tissue preservative

47
Q

Oxidizing Agents like perozygens:

A

denature proteins and lipids

48
Q

Hydrogen peroxide is good for ______________ of contaminated surfaces but not a good __________ for wounds.

A

disinfection; antiseptic

49
Q

What’s used to preserve meats like hot dogs?

A

Sodium nitrite

50
Q

What are organic acids used for?

A

the control of molds and bacteria in foods and cosmetics

51
Q

What two antibiotics prevent the spoilage of cheese?

A

nisin and natamycin

52
Q

What are the most resistant to chemical biocides?

A

prions

53
Q

What are the least resistant to chemical biocides?

A

viruses with lipid envelopes