Chapter 7-Control of Microbe Growth Flashcards
(91 cards)
1
Q
refers to microbial contamination
A
sepsis
2
Q
the absence of significant contamination
A
asepsis
3
Q
aseptic surgery techniques prevent what?
A
microbial contamination of wounds
4
Q
removing all microbial life
A
sterilization
5
Q
killing C. botulinum endospores
A
commercial sterilization
6
Q
C botulinum endospores
A
deadly toxins
7
Q
removing pathogens (vegetation)
A
disinfection
8
Q
removing pathogens from living tissue
A
antisepsis
9
Q
removing microbes from a limited area
A
degerming
10
Q
lowering microbial counts on eating utensils
A
sanitization
11
Q
killing microbes
A
biocide/germicide
12
Q
inhibiting, not killing, microbes
A
bacteriostasis
13
Q
stopping from dividing
A
bacteriostasis
14
Q
growth is measured by _____ and ______ of the number of cells
A
generations, log10
15
Q
refers to doubling over time (binary fission)
A
genertion
16
Q
a functional representation of generation of generations over time
A
log
17
Q
one log decrease= ____ of population killed
A
90%
18
Q
effectiveness of antimicrobial treatment depends on
A
- number of microbes
- environment
- time of exposure
- microbial
19
Q
Large populations take _____ to kill
A
longer
20
Q
_____ populations are killed more quickly
A
small
21
Q
a population is called a ____
A
load
22
Q
______ environments increase effectiveness
A
warm
23
Q
____ environments decrease effectiveness
A
cool
24
Q
fats and proteins create a _____ to treatments
A
barrier
25
actions of microbial control agents
alteration of membrane permeability
damage to proteins
damage to nucleic acid
26
leaking of cellular content
| interferes with growth
alteration of membrane permeability
27
heat and chemicals can denature protein by breaking bonds
damage to proteins
28
DNA or RNA damage
damage to nucleic acids
29
extended exposure increases effectiveness
time of exposure
30
endospores and capsules resistance to treatment and protecting of the organism
microbial characteristics
31
lowest temperature a which all cells in a culture are killed in 10 minutes
thermal death point
32
time during which all cells in a culture are killed
thermal death time
33
minutes to kill 90% of a population at a given temperature
decimal reduction time
34
moist and heat _____
proteins
35
steam under pressure
autoclave
36
moist, heat, and autoclave can ____ microbe
kill
37
reduces spoilage organisms and pathogens
pasteurization
38
70c for 15 sec
high temperature short time
39
140c for less than 1sec
ultra high temperature
40
63c for ____
30 minutes
41
equivalent treatments for pasteurization
63 for 30min
72c for 15sec
140c for less than 1sec
42
kills by oxidation
dry heat sterilization
43
how to kill by oxidation
dry heat
flaming
incineration
hot air sterilization
44
equivalent to dry heat sterilization
hot air at 170c for 2hrs
| autoclave at 121c for 15min
45
removes microbes > 0.3 nanometer
HEPA
46
removes microbes > .22 nanometer
membrane filtration
47
most common size of microbes
.22 nanometer
48
what size microbe retains viruses
.01 nanometer
49
low temperature
high pressure
desiccation
osmotic pressure
physical methods of microbial control
50
inhibits microbial growth
low temperature- can be refrigeration, deep freezing, lyophilization (drying)
51
denatures proteins
high pressure
52
prevents metabolism
desiccation
53
causes plasmolysis
osmotic pressure
54
xrays, gamma rays, electron beams
ionizing radiation
55
ionizes water to release OH
| damages DNA
ionizing radiation
56
UV, 260nm
| damages DNA
nonionizing radiation
57
kill by heat, not especially antimicrobial
microwaves
58
4 principles of effective disinfection
concentration of disinfectant
organic matter
pH
Time
59
most common disinfectant
bisphenol and phenol
60
disrupt plasma membrane synthesis of staphylococcus and streptococcus species
hexaclorophene bisphenol
61
disrupt plasma membrane synthesis or Gram
hexaclorophene triclosan
62
found in antimicrobial/ antibacterial liquid soap
hexaclorophene triclosan
63
Lysol
hexaclorophene bisphenol/ phenol
64
halogens
iodine and chlorine
65
in aqueous alcohol
iodine-tinctures
66
in organic molecules
iodine-iodophers
67
alter protein synthesis and membrane
iodine
68
hypochlorous acid (HOCl)
Chlorine-Bleach
69
chlorine + ammonia
Chlorine- Chloramine
70
oxidizing agents (removal or loss of electrons
Chlorine
71
Alcohols
Ethanol, Isopropanol
72
denature proteins
dissolve lipids
require water (70% EtOH)
alcohol-ethanol/isopropanol
73
Heavy Metals
Ag, Hg, Cu, Oligodynamic action
74
silver nitrate may be used to prevent gonorrheal ophthalmia neonatorum
Ag, Hg, Cu
75
silver sulfadiazine used as a topical cream on burns
Ag, Hg, Cu
76
Copper sulfate is an algicide
Ag, Hg, Cu
77
denature proteins
oligodynamic action
78
degerming or physically removing microbes
soap
79
sanitizing
acid-anionic detergents (negatively charged)
80
bactericidal
denature proteins
disrupt plasma membrane
common in household cleaners
quaternary ammonium compounds (cationic detergents)
81
organic acids
| nitrites
chemical food preservatives
82
- inhibit metabolism of fungus and bacteria
- sorbic acid, benzoic acid, & calcium propionate
- control molds and bacteria in foods and cosmetics
organic acids
83
- prevents endospore germination
| - Clostridium and Bacillus
Nitrites
84
-inactive proteins by cross linking with functional groups
(-NH2, -OH, -COOH, -SH)
-use medical equipment (glutaraldehyde, formaldehyde, & orthophthalaldehyde)
aldehydes
85
denature proteins
| use liquid, heat sensitive material (ethylene oxide)
gaseous sterilants
86
- oxidizing agents
- use contamination surfaces and skin (antiseptics)
- -- O3, H2O2, peracetic acid
peroxygens
87
metal rings dipped in test bacteria are dried
dilution test
88
dried cultures are placed in disinfectant for 10 minutes at 20c
dilution test
89
rings are transferred to culture media to determine whether bacteria survived treatment
dilution test
90
plate bacteria, place disks dipped in disinfectant and incubate, measure zone of inhibition
disk diffusion method
91
zone on plate where no bacteria can grow
zone of inhibition
