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Flashcards in Chapter 9 Deck (172)
1

_____ destroys all viable microbes, endospores.

Sterilization

2

_____ is not for living tissue.

sterilization

3

_____ destroys vegetative pathogens, not endospores.

disinfection

4

_____ is not 100% (not sterilization)

disinfection

5

_____ is mechanical removal of microbes to safe levels.

sanitization

6

Dishwashing is an example of ___.

sanitization

7

_______ is the reduction of microbe numbers on skin.

antisepsis

8

Hand sanitizer and soap are examples of _____.

antisepsis

9

Antisepsis is used for _____.

living tissue

10

Microbial Resistance from the highest resistance to the least resistance.

prions
bacterial endospores
mycobacterium
staphylococcus & pseudomonas
protozoan cysts
protozoan trophozoites
most gram negative bacteria
fung and fungi spores
nonenveloped viruses
most gram positive bacteria
enveloped viruses

11

_____ are the target of sterilization

bacterial endospores

12

Term ending in -cidal means to ____.

kill

13

Bleach, iodine, or heat are forms of ______.

disinfection

14

_____ are chemical agents capable of destroying endospores.

sterilization

15

Alcohol and surgical hand scrubs are agents for ______.

antisepsis/degermation

16

A _____ is a chemical agent that destroys bacteria except for those in the endospore stage.

bactericide

17

A ____ is a chemical that can kill fungal spores, hyphae, and years.

fungicide

18

A ___ is any chemical known to inactive viruses, especially on living tissues.

virucide

19

A term ending in -static means the ability to prevent _______.

multiplication/growth

20

A ____ is an agent capable of destroying bacterial endospores.

sporicide

21

A sporicidal agent can also be a sterilant because it can destroy the most resistant of all ____.

microbes

22

______ and microbicide are additional terms for chemical agents that kill microorganisms.

germicide

23

_____ agents prevent the growth of bacteria on tissues or on objects in the environment.

bacteristatic

24

____ agents chemically inhibit fungal growth.

fungistatic

25

Materials used to control microorganisms in the body (antiseptics and drugs) often have ___ effects because many microbicidal compounds can be highly toxic to human cells.

microbistatic

26

_____ is defined as the growth of microorganisms in the blood/tissues.

sepsis

27

_____ prevents the entry of infectious agents into sterile tissues (prevent infection).

asepsis

28

______ are the range of methods depending on task.

aseptic techniques

29

Chemical agents called antiseptics are applied directly to _____, wounds, and surgical incisions to destroy or inhibit vegetative pathogens.

exposed body surfaces

30

Factors affecting Death Rate

1. Number of microbes present
2. The nature of the microbe population
3. Temperature and pH of the environment
4. The concentration (dose, intensity) of the agent
5. The mode of action of the agent
6. The presence of interfering organic matter

31

The four targets of antimicrobials.

1. The cell wall
2. The cell membrane
3. Cellular synthetic processes
4. Protein Function

32

____ is a phenomenon that involves the permanent termination of an organsims's vital processes

death

33

A chemical agent can damage the cell wall by blocking its synthesis or _____ the cell wall.

digesting

34

Effects of Impacting cell wall

?

35

By disrupting cell membranes there is a loss of ______ which causes ____.

selective permeability
cell lysis
i.e. detergents

36

Some antimicrobial processes can affect ______.

cellular synthetic processes

37

Some antimicrobials affect cellular synthetic processes by interrupting of protein synthesis impacts _____ and ____.

metabolism and multiplicationSome antimicrob

38

Some antimicrobials affect cellular synthetic processes which cause ________.

damage to genetic material (causing mutations)

39

Most _____ need to be folded to function.

proteins

40

Protein _____ inactivates protein function.

denaturation

41

Heat, alcohol, acids, and other compounds can also disrupt ______ leading to a loss in function.

active sites

42

_____ is a method of physical control.

heat

43

_____ temperatures are microbicidal.

elevated

44

_____ temperatures are microbistatic.

lower

45

Methods of controlling microorganisms into two broad categories: ____ and ____.

chemical and physical

46

Moist heat and dry heat differ in their modes of ____ as well as in their ____.

action
efficiency

47

____ heat operates at lower temperatures and faster working than ____ heat.

moist
dry

48

Although many cellular structures are damaged by moist heat, its most microbicidal effect is the _____ and _____ of proteins, which quickly and permanently halts cellular metabolism.

coagulation and denaturation

49

____ heat dehydrates cell and denatures proteins. The lack of water actually increases the stability of some protein conformations, necessitating the use of higher temperatures when ____ heat is employed as a method of microbial control.

dry
dry

50

_____ heat at very high temperatures, oxidizes cells, burning them to ash.

dry
i.e.. when an inoculating loop in incinerated

51

There sterilization by moist and dry heat takes place at ____ temperature.

121C

52

With moist heat it takes ____ minutes to sterilize.

15 minutes

53

With dry heat it takes ____ minutes to sterilize.

600 minutes

54

_______ exhibit the greatest heat resistance.

bacterial endospores

55

The destruction of spores usually requires temperatures above ____.

boiling

56

Vegetative cells and fungi are the ____ heat resistant to both moist and dry heat.

least

57

Vegetative cells vary in their heat sensitivity. Death times with moist heat range from 50C for 3 minutes (Neisseria gonorrhoea) to ___C for ___ minutes for Staphylococcus aureus.

60C
60 minutes

58

____ are surprisingly resistant to heat, with a tolerance range extending from 55C for 2-5 minutes (_____) to 60C for 600 minutes (_______).

viruses
adenoviruses
hepatitis A virus

59

Heat treatment of perishable substances must render the product free of agents of spoilage or disease without affecting the ____ and ____ of processing.

speed and cost

60

______ is the shortest length of time required to kill all microbes at a specified temperature.

Thermal death time (TDT)

61

______ is the lowest temperature required to kill all microbes in a sample in 10 minutes.

Thermal death point (TDP)

62

The three common methods of moist heat.

1. Steam under pressure
2. Pasteurization
3. Boiling water

63

_____ is a technique in which heat is applied to liquids to kill potential agents of infection and spoilage, while at the same time retaining the liquids flavor and food value.

pasteurization

64

Autoclaves are used for ____.

sterilization

65

Autoclaves cannot sterilize just with steam so it must be steamed ______. An _____ in pressure = higher temperatures than possible without increased pressure.

under pressure
increase

66

Autoclaves sterilize at ___ psi's, at 121C, for ___ minutes.

15 psi
15 minutes

67

______ kill all endospores.

autoclaves

68

Home pressure cookers function on the same basic principle as _____.

autoclaves

69

Heat resistant materials such as glassware, cloth (surgical dressings), metallic instruments, liquids, paper, some media, and some heat resistant plastics are sterilized by _____.

autoclaves

70

Autoclaves are ineffective for sterilizing substances that repel moisture (______) and for those that are harmed by it (______).

oils and waxes
powders

71

_____ disinfects liquids.

pasteruization

72

Pasteurization may not kill ____.

all organisms

73

Pasteurization does not kill _____.

endospores

74

Boiling water is for disinfection, not ____.

sterilization

75

To disinfect materials, they must be exposed to boiling water for _____.

30 minutes

76

Boiling water causes ____.

protein denaturation

77

Hot air sterilization is a method of _____ heat that takes place in an oven.

dry heat

78

Hot air sterilization is used for _____ items and it takes hours.

heat resistant

79

Hot air sterilization destroys ____.

endospores

80

_____ is a form of dry heat with a flame.

Incineration

81

_____ turns microbes to ashes and gas.

incineration

82

In micro labs ____ is a common practice because it destroys everything.

incineration

83

The principal benefit of _____ is to slow growth of cultures and microbes in food during processing and storage. I merely slows the activities of most microbes, not killed (rare).

cold treatment

84

Freezing temps from ____ to ____ are often used in research labs to preserve cultures of bacteria, viruses, and fungi for long periods.

-70C to -135C

85

______ grow slowly at freezing temperatures and can secrete toxic products.

psychrophiles

86

Vegetative cells directly exposed to normal room air gradually become dehydrated or ____.

desiccated

87

Spirochete of _____ and Neisseria gonorrhoeae die after a few hours of air drying or ______.

syphilis
desiccation

88

Endospores of Bacillus and _____ are viable for thousands of years under extremely arid conditions.

Clostridium

89

Freeze drying is called _______, which is a common method of preserving microorgansims and other cells in a viable state for many years.

lyophilization

90

Chilling, freezing and desiccation should not be construed as method of ____ or ____.

disinfection or sterilization

91

_____ is defined as energy emitted from atomic activities and dispersed at high velocity through matter of space.

radiation

92

The forms of radiation suitable for microbial control gamma rays, ____, and _____.

x rays
ultraviolet radiation

93

Ionizing radiation includes _____ and ____.

gamma rays and x rays

94

Nonionizing radiation includes _____.

ultraviolet radiation

95

Radiation is used to destroy microbes or _____ that might be present in or on food.

insects

96

_____ ability of radiation is related to wavelength of the radiation.

penetrating

97

Radiation is mot useful for surfaces such as ____, ____, and tables.

food
surgical tools

98

Ionizing radiation is _____ energy and _____ penetrating.

high
very

99

______ radiation breaks the DNA backbone causing structural damage.

Ionizing

100

______ radiation is used for foods, poultry, drugs/medical supplies, mail.

ionizing radiation

101

_____ radiation damages DNA (thymine dimers)

nonionizing

102

_____ radiation is not as penetrating as _____ radiation.

nonionizing
ionizing

103

_____ radiation is used for disinfection not sterilization.

nonionizing

104

_____ radiation works on endospores with long exposure.

nonionizing

105

_____ radiation is used for hospital rooms, schools, food prep areas, and dental offices.

nonionizing

106

______ pass liquid or gas through a filter with small pore size.

filtration

107

Filtration is a method of ____ removal.

mechanical

108

No heat is involved with ____.

filtration

109

Filtration is an efficient method of removal of _______.

airborne contaminants

110

High efficiency particulate air (HEPA) filters are used in hospital rooms and sterile rooms which are a form of _____.

filtration

111

Microbiological ____ are thin membranes of cellulose acetate, polycarbonate, and a variety of plaster materials (teflon, nylon) whose pore size can me carefully controlled and standardized.

filters

112

Adding large amounts of slat or sugar to foods creates a hypertonic environment for bacteria in the foods causing ______ and making it impossible for the bacteria to ____.

plasmolysis
multiply

113

Picking, smoking and drying foods have been used for centuries to _____.

preserve foods

114

Osmotic pressure is never a _____ technique.

sterilizing technique

115

Antimicrobial chemicals occur in liquids, gaseous, or even solid state, and they range from disinfectants and ______ to sterilants and preservatives.

antiseptics

116

Approximately ____ different antimicrobial chemical agents are manufactured. Approximately ____ are used routinely in health care and the home.

10,000
1,000

117

_____ solutions are when chemicals are dissolved in pure water as the solvent.

aqueous solutions

118

____ are chemicals dissolved in pure alcohol or water-alcohol mixtures.

tinctures

119

Germicides are evaluated in terms of their ______ in destroying microbes in medical and dental settings.

effectiveness

120

Factors that affect the germicidal activity of chemicals.

1. Nature of microorgansims being treated
2. Nature of the material being teated
3. Degree of contamination
4. Time of exposure
5. Strength and chemical action of the germicide

121

Mycobacterium tuberculosis requires a concentration of ____ and ____ for chemical destruction.

50 ppm and 50 seconds

122

Entamoeba cysts (protozoa) requires a concentration of ____ and _____ for chemical destruction.

0.1 ppm and 150 minutes

123

Hepatitis A virus requires a concentration of ____ and ____ for chemical destruction.

3 ppm and 30 minutes

124

The agent ______ is used on Mycobacterium tuberculosis, Entamoeba cysts, and Hepatitis A virus.

chlorine

125

The agent _____ is used on Staphylococcus aureus, Escherichia coli, and Poliovirus.

Ethyl Alcohol

126

Staphylocoocus aureus requires a concentration of ______ and ____ for chemical destruction.

70% and 10 minutes

127

Escherichia coli requires a concentration of ______ and ____ for chemical destruction.

70% and 2 minutes

128

Poliovirus requires a concentration of ______ and ____ for chemical destruction.

70% and 10 minutes

129

Halogens affect _____.

protein function

130

Two types of halogens are ______ and _____.

iodine and chlorine

131

____ is a topical antiseptic which is not very soluble, usually combined with soluble agents in a "tincture"

Iodine

132

_____ is a disinfectant that kills bacteria, endospores, fungi, and viruses.

chlorine

133

_______ mode of action is highly toxic oxygen free-radicals.

hydrogen peroxide

134

When hydrogen peroxide is used as an antiseptic, ____ wound cleansing, skin antiseptid.

3%

135

Higher concentrations of ____ work better on endospores. Use on surfaces only, not skin.

hydorgen peroxide

136

______ disrupt cell walls and membranes and coagulate proteins.

phenolics

137

____ is a phenolic, as well as the triclosan found in some antibacterial soaps.

lysol

138

_____ is in products such as clothing, kitchenware, furniture as well as antibacterial soaps/body washes, toothpastes, and some cosmetics.

triclosan

139

Animal studies have shown that ___ alters hormone regulation.

triclosan

140

Triclosan is not known to have effect on ____.

humans

141

Triclosan may contribute to _____ resistance.

antibiotic

142

FDA is engaged in an ongoing scientific and regulatory review of _____.

triclosan

143

____ targets cell membranes and protein structure.

chlorhexidine

144

Chlorhexidine is a bactericidal for ______, but not endospores.

both gram positive and gram negative bacteria

145

Alcohols are most effective at concentrations of _____ in water.

50% -95%

146

_____ kill by dissolving cell membranes.

kill

147

____ coagulate proteins.

alcohols

148

Only ______ and _____ have the activity suitable for microbial control.

ethanol and isopropanol

149

Alcohols ____ endospores.

do not kill

150

____ contain quaternary ammonia compounds (QUATS)

detergents

151

Detergents provide ____ disinfection.

low level

152

Detergents disrupt _____.

membrane integreity

153

Plain soap is a method of ____ removal.

mechanical

154

Heavy metal compounds antimicrobial effects are in ______.

very small amounts

155

Heavy metal compounds ____ proteins.

inactivates

156

Drawbacks to using metals in microbial control are that it is very ____ to humans and often causes allergic reactions. Large quantities of biological fluids and wastes ____ their actions.

toxic
neutralize

157

Microbes can develop ____ to heavy metal compounds.

resistance

158

Aldehydes ____ proteins.

inactivate

159

Types of disinfectants include aldehydes and ____.

gaseous chemosterilants

160

Two types of aldehydes are ____ and ____.

formaldehyde (gas)
glutaraldehyede (hospital instruments)

161

Glutaraldehyde is somewhat ___, especially with increased pH and temperature.

unstable

162

Formaldehyde is extremely ____ and is irritating to skin and mucous membranes.

toxic

163

Ethylene oxide is ____ and must be combined with high percentage of carbon dioxide or fluorocarbon.

explosive

164

Gaseous chemosterilants ___ proteins, and alter DNA replication.

denature

165

Gaseous chemosterilants are chemicals that ____ in a closed chamber without heat.

sterilize

166

Ethylene oxide kills ____ .

all microbes and endospores

167

Hospitals use _____ to sterilize large heat sensitive items.

ethylene oxide

168

Ethylene oxide is a _____.

gaseous chemosterilant

169

Bacterial endospores and prions are in the ____ category.

high resistance

170

____ are proteinaceous infectious particles . (BSE, CJD)

Prions

171

What is the best way to ensure endospore killing?

use hydrogen peroxide
aldehydes
ethyne oxide
bleach idoine

172

Prions are not removed by most methods...so, how do
we get rid of them

Prions are the most difficult infectious particles to destroy. Currently, a combination of very high temperature and sodium hydroxide is used