chapter 10 pt 2

Question 1

physical methods of control

Answer 1

heat, cold, desiccation, radiation, filtration

Question 2

moist heat

Answer 2

lower temp than dry heat and shorter exposure time
-coagulation and denatures proteins

Question 3

dry heat

Answer 3

high temperature, dehydrates so proteins cant fold, incineration

Question 4

thermal death time

Answer 4

shortest length of time needed to kill all test microbes at a specific temperature

Question 5

thermal death point

Answer 5

lowest temp to kill microbes in a sample in ten minutes

Question 6

moist heat methods

Answer 6

-sterilization from steam under pressure
-autoclave 121 celsius for 10-40 min
-steam has to reach the surfaces
-cant be heat sensitive item
-denatures proteins and destroys membranes and DNA

Question 7

nonpressure steam

Answer 7

tyndallization
-disinfectant
-canned foods and lab media

Question 8

tyndallization

Answer 8

intermitten sterilization for things that cant stand autoclave
-free floating steam for 30 - 60 minutes to kill vegetative spores then incubate and steam again

Question 9

why repeat cycle for 3 days of incubating and steaming for tyndallization?

Answer 9

bc vegetative can come back from germination
-this is NOT sterilization bc not killing spores just vegitative state

Question 10

boiling water

Answer 10

100 celsius for 30 minutes for non spore forming pathogens
-disinfection

Question 11

pasteurization

Answer 11

heat without destroying milk
-63-66 degress for 30 min (batch)
-71 for 15 seconds (flash)
-NOT sterilization doesnt kill spore forming pathogens and many nonpathogenic microbes
-just lowers microbe count

Question 12

dry heat is

Answer 12

flame or electric heating coil
-a dry oven will coagulate/ dehydrate proteins

Question 13

is cold good for killing?

Answer 13

no it preserves microbes
-slows growth
-preserves food and mecia and cultures
-when thaw microbe resumes growth

Question 14

dessication

Answer 14

remove water molecules for metabolic inhibition
-preservation technique
-not useful bc many cells can grow w out water

Question 15

lyophilization

Answer 15

freeze drying to preserve
-type of desiccation
-freeze dry yeast

Question 16

ionizing radiation

Answer 16

deep pentrating power that can force electrons out of orbit therefore breaking DNA
-gamma rays, x rays, cathode rays
-sterilize medical supplies and food (rasberries)

Question 17

nonionizing

Answer 17

-uv
-little pentration
-object has to be directly exposed (lab)
-pyrimidine dimers

Question 18

what can nonionizing sterilize?

Answer 18

water, air and surfaces

Question 19

filtration

Answer 19

physical removal of microbes through a filter
-mask that blocks droplets or bacterial and viruses
-good for heat sensitive liquids and hostpial air
-doesnt kill just traps microbesz

Question 20

chemical methods of control

Answer 20

-disinfectant
-antiseptics
-sterilants
-degermers
-preservatives

Question 21

advantages of chemicals

Answer 21

-fast in low concentrtions
-water or alcohol soluble (stable)
-low toxicity
-penetrating
-noncorrosive and nonstaining
-afforable and available

Question 22

chemical levels

Answer 22

-high level germicides
-intermediate level
-low lever

Question 23

high level germicide

Answer 23

-kill endospores
-MIGHT be sterilants
-good if object cant take heat of autoclave
-things going into the body

Question 24

intermediate level

Answer 24

kill fungal spores NOT endospores, tubercle bacillus and viruses
-disinfect devices that contact mucous membranes but are not invasive devices
-kills what will make you sick

Question 25

low level

Answer 25

eliminate only vegitative bacteria
-some viruses and vegitative fungal cells
- to clean surfaces that touch skin but not mucous membranes

Question 26

what affects germicidal activity of chemicals?

Answer 26

-nature of material being treated
-degree of contamination
-time of exposure
-strength and chemical action of the germicide

Question 27

germicidal categories

Answer 27

-halogens
-phenolics
-chlorhexidine
-alcohol
-hydrogen peroxide
-aldehyde
-gases
-detergent and soap
-heavy metals
-dyes
-acids and alkalines

Question 28

chlorine

Answer 28

-chlorine
-hypochlorites (bleach)
-denatures porteins by messing with disulfide bonds
-intermediate level so cant kill spores
-unstable in sun and inactivated by organic material (Pee and poo)

Question 29

chloramines

Answer 29

when chlorine is inactive

Question 30

halogens

Answer 30

chlorines and iodines

Question 31

iodine

Answer 31

-iodophors (betadine)
-messes up disulfide bonds
-intermediate level
-milder medical and dental degerming agents, disinfectants and oinments

Question 32

phenolics

Answer 32

-lysol
-cell wall and proteins
-low to intermediate level
-bactericidal, fungicidal, viricidal NOT sporicidal
-triclosan additive to soap

Question 33

chlorhexidine

Answer 33

-hospitals
-surfactant and protein denaturant
-low to intermediate
-hibiclens and hibitane
-antiseptic for or scrubs, skin clearning, burns. handwashing in hospital, cosmetic creams, toothpaste, eye drops, deodorant, mouthwash
-controls MRSA and acinetobacter in hospitals

Question 34

alcohols

Answer 34

ethyl or isopropyl 50-95%
-acts like surfactant to dissolve me,brane ;lipids and coagulating proteins of vegetative bacterialc ells and funi
-intermediate level
-best is 70% bc u need water to coagulate proteins

Question 35

hydrogen peroxide

Answer 35

makes hydroxyl free radicals that damage protein and DNA while it also decomposes to oxygen
-toxic to anaerobes
-low conceptration is antispetic
-high concentration is sporicidal, bactericidal, viricudal, fungicidal
-sterilizes medical equipment (dental tools and endoscopes)

Question 36

high concentration of hydrogen peroxide

Answer 36

strong and dangerous

Question 37

aldehydes

Answer 37

alkylates proteins and DNA
-glutaraldehyde and formaldehyde
-rapid and effective

Question 38

gluteraldehyse

Answer 38

in 2 % it is used as a sterilant for heat sensitive instruments
-high level

Question 39

formaldehyde

Answer 39

disinfectant, presercative, toxic
-formalin is 37% aqueous
-intermediate to high level

Question 40

gases and aerosols

Answer 40

ethylene oxide and propylene oxide
-strong alkylating agents
-high level
-disinfect and sterilize plasmic and devices and food
-things that cant be autoclaves or exposed to steam/ heat?

Question 41

detergent and soaps

Answer 41

quaternary amonia compounds that are surgactants altering membrane permeability of bacteria and fungi
-cationic detergent
-low level

Question 42

heavy metals

Answer 42

solutions of silver and mercury kill vegitative cells in low concentrations by inactivating proteins
-oligodynamic action
-low level

Question 43

what are the metals

Answer 43

merthiolate, silver nitrate and silver
-toxic if ingested or absorbed

Question 44

what is silver added to?

Answer 44

catheters, IV lines, and prostheses to prevent biofilms and infections

Question 45

dyes

Answer 45

aniline dyes have antimicrobial components
-active against gram positive bacteria and fungus
-antisepsis and wound treatment
-low level

Question 46

acids and alkalis

Answer 46

low level
-organic acids present spore germination, bacterial and fungal growth
-food preservation

Question 47

acetic acid

Answer 47

bacterial growthp

Question 48

propionic acid

Answer 48

retards mold
-retard my mold y te doy una propina

Question 49

lactic acid

Answer 49

anerobic bacterial growth
-lack oxy

Question 50

benzoic and sorbic acid

Answer 50

inhibit yeast

Question 51

sodium hydroxide

Answer 51

destroys prions

Question 52

ceviche

Answer 52

cooked by citrus bc the ph kills microbes