sterilization and disinfection

Question 1

Destruction and removal of all forms of microbial life, including endospores

Answer 1

sterilization

Question 2

Usually done by steam under pressure or a sterilizing gas such as ethylene oxide.

Answer 2

sterilization

Question 3

Sufficient heat treatment to kill endospores of Clostridium botulinum in canned foods.

More resistant endospores of thermophilic bavteria may survive, but they will not
germinate and grow under normal storage condition.

Answer 3

commercial sterilization

Question 4

endospore of ___ in canned good

Answer 4

clostridium botulinum

Question 5

Destruction of vegetative pathogens.

May make use of physical or chemical methods

Answer 5

disinfection

Question 6

Destruction of vegetative state pathogens on living tissues.

Treatment is always by chemical antimicrobials.

Answer 6

antisepsis

Question 7

Removal of microbes from a limited area such as the skin around the injection site.

Mostly a mechanical removal by an alcohol-soaked swab.

Answer 7

degerming

Question 8

Treatment intended to lower microbial counts on eating and drinking utensils to
safe public health levels.

Maybe done with a high temperature washing or by dipping into a chemical
disinfectant.

Answer 8

sanitation

Question 9

Bacterial population die at a constant rate when heated or treated with
antimicrobial agents.

Answer 9

rate of microbial growth

Question 10

Factors affecting the effectiveness of
antimicrobial treatments:

Answer 10

The number of microbes

Environmental influences

Time of exposure

Microbial characteristics

Question 11

kills microorganism primarily by coagulation of proteins
(denaturation), which caused by breakage of the hydrogen bonds that hold the
protein.

Answer 11

moist heat

Question 12

kills vegetative bacterial and fungal pathogens and
almost all viruses within 10 minutes, less effective on endospores.

Answer 12

Boiling or flowing steam

Question 13

preferred use of Boiling or flowing steam

Answer 13

Dishes, basins, pitchers, various equipments

Question 14

mechanism of action of boiling or flowing steam

Answer 14

Protein denaturation

Question 15

very effective method of sterilization, at about 15 psi
(121 degC), all vegetative cells and their endospores are killed in about 15
mins.

Answer 15

autoclaving

Question 16

autoclaving is used in

Answer 16

Microbiological media, solutions, linens, utensils, dressings,
equipment, and other items that can withstand temperature and pressure.

Question 17

mechanism of action in autoclaving

Answer 17

protein denaturation

Question 18

the use of mild heating which is sufficient to kill the
microorganisms that can cause spoilage problem without really damaging the
taste of the product.

Answer 18

pasteurization

Question 19

at what degree is the heat treatment for milk

Answer 19

Heat treatment for milk (72 degC for about 15 secs) kills all pathogens and
most non-pathogens

Question 20

pasteurization is used in

Answer 20

Milk, cream, and certain alcoholic beverages (beer and wine)

Question 21

MOA of pasteurization

Answer 21

protein denaturation

Question 22

kills by oxidation effect

Answer 22

dry heat

Question 23

Very effective method of sterilization

Answer 23

direct flaming

Question 24

direct flaming is used in

Answer 24

inoculating loops

Question 25

MOA of direct flaming

Answer 25

Burning contaminants to ashes

Question 26

very effective method of sterilization

Answer 26

incineration

Question 27

incineration is used in

Answer 27

Paper cups, contaminated dressings, animal carcasses, bags and wipes.

Question 28

MOA of incineration

Answer 28

burning to ashes

Question 29

very effective method of sterilization but requires temp.at 170 degC for about 2 hours.

Answer 29

Hot-air sterilization

Question 30

Hot-air sterilization is used in

Answer 30

Empty glasswares, instruments, needles and glass syringes.

Question 31

MOA of hot-air sterilization

Answer 31

oxidation

Question 32

the passage of a liquid or gas through a screen like materials with pores small enough to retain microbes.

Answer 32

filtration

Question 33

filtration is used in

Answer 33

Sterilizing liquids (enzymes, vaccines) that are destroyed by heat

Question 34

MOA of filtration

Answer 34

Separation of bacteria from suspending liquid

Question 35

Has a bacteriostatic effect

Answer 35

refrigeration

Question 36

ref.. is used in

Answer 36

Food, drug and culture preservation

Question 37

MOA of ref..

Answer 37

Decreased chemical reactions and possible changes in protein.

Question 38

an effective method for preserving microbial cultures, in which cultures are quick-frozen

Answer 38

deep-freezing

Question 39

cultures are quick-frozen between

Answer 39

-50 degC and 95 degC

Question 40

deep-freezing is used in

Answer 40

Food, drug and culture preservation

Question 41

MOA of deep-freezing

Answer 41

Decreased chemical reactions and possible changes in protein.

Question 42

Most effective method for long term preservation of microbial culture Water removed by high vacuum at low temp.

Answer 42

Lyophilization

Question 43

Lyophilization is used in

Answer 43

Food, drug and culture preservation

Question 44

MOA of Lyophilization

Answer 44

Decreased chemical reactions and possible changes in protein.

Question 45

Preservation of colors, nutrient values

Answer 45

high pressure

Question 46

high pressure is used in

Answer 46

fruit juices

Question 47

high pressure MOA

Answer 47

Alteration of molecular structure of proteins and carbohydrates.

Question 48

Involves removing of water from microbes; primarily bacteriostatic

Answer 48

desiccation

Question 49

desiccation is used

Answer 49

food preservation

Question 50

MOA of dessication

Answer 50

Disruption of metabolism

Question 51

Results in loss of water from microbial cells

Answer 51

osmotic pressure

Question 52

osmotic pressure is used in

Answer 52

food preservation

Question 53

MOA of osmotic pressure

Answer 53

Plasmolysis

Question 54

kills microorganism

Answer 54

radiation

Question 55

2 ways of killing microorganism thru radiation

Answer 55

ionizing and non-ionizing

Question 56

Not widespread in routine sterilization

Answer 56

Ionizing (gamma rays or high enery electron)

Question 57

ionizing use:

Answer 57

Sterilizing pharmaceuticals and medical and dental supplies

Question 58

MOA of ionizing

Answer 58

Destruction of DNA

Question 59

radiation not very penetrating

Answer 59

non-ionizing

Question 60

non-ionizing is used in

Answer 60

Control of closed environment with UV lamp

Question 61

principles of effective disinfection

Answer 61

read the label nature of material being disinfected disinfectant effect

Question 62

chemical substances that applied to non-living objects or surfaces to inhibit the growth of microorganisms.

Answer 62

disinfectant

Question 63

prevent the spreading of germs and bacteria to people by sterilizing the surfaces where they are applied and they are largely used in homes for cleaning bathrooms, kitchens and floor.

Answer 63

disinfectant

Question 64

disinfectant used in healthcares

Answer 64

hydrogen peroxide

Question 65

common disinfectant

Answer 65

alcohols, oxidizing agents and bleaches.

Question 66

chemical agents used to destroy or prevent the growth of microorganisms that could cause infections and diseases.

Answer 66

antiseptic

Question 67

applied on broken skins to kill disease-causing microorganisms that might have infected the area or keep them away from these areas and are applied on living tissues with zero injurious effect on the body surface where it is applied.

Answer 67

antiseptics

Question 68

may also act as sanitizer for cleaning hands to remove bacteria when a person cannot wash hands.

Answer 68

antiseptics

Question 69

Applied on non-living items Inhibit the growth of microorganisms on the surfaces Disinfect areas that can spread germs Very toxic and injurious when used on living tissue

Answer 69

disinfectant

Question 70

Applied on living tissues Kill and destroy microorganisms on living tissue Reduce the risk of infections by germs. Have no injurious effect on living tissue.

Answer 70

antiseptics

Question 71

Used in: Original surgical antiseptic. Mechanism of Action: Denatures proteins and disrupt cell membrane

Answer 71

phenol (carbolic acid)

Question 72

Used in: Disinfectants, antiseptics and solvent in tincture Mechanism of Action: Denatures proteins and disrupt cell membrane

Answer 72

alcohol

Question 73

Used in: Disinfectants, antiseptics and water purification Mechanism of Action: Denatures proteins and disrupt cell membrane

Answer 73

Halogen (iodine, chlorine, bromine)

Question 74

Used in: Disinfectants, antiseptics for deep wound , water purification and sterilization of food processing and medical equipments. Mechanism of Action: Denature protein by oxidation

Answer 74

Oxidizing Agents (peroxides,ozone)

Question 75

Mechanism of Action: Decrease surface tension of water and disrupt cell membranes Used in: Soaps, degerming reagents, antiseptics

Answer 75

surfactants

Question 76

Used in: Fungistat in paints, silver nitrate cream, surgical dressing, burn cream and catheter. Mechanism of Action: Denature protein

Answer 76

Heavy Metals (arsenic, mercury, silver copper)

Question 77

Used in: Disinfectan and embalming fluid Mechanism of Action: Denature protein

Answer 77

Aldehydes (Formaldehyde,glutaraldehyde)

Question 78

Used in: Sterilization of heat and water sensitive objects Mechanism of Action: Denature protein

Answer 78

Gaseous analytes (ethylene oxide)

Question 79

Used in: Disinfectants and treatment of infectious diseases Mechanism of Action: Act against cell wall, cell membranes, protein synthesis and DNA replication.

Answer 79

antimicrobials

Question 80

Actions of microbial control agents

Answer 80

Alteration of membrane permeability Damage to protein and nucleic acids