Microbiology: Ch 11-Physical And Chemical Agents For Microbial Control

Front 1

Decontamination

Back 1

Decontamination-

procedures that involve the DESTRUCTION or REMOVAL of contaminants.

Front 2

Contaminants

Back 2

Contaminants-

defined as microbes present at a given place and time that are UNDESIRABLE or UNWANTED.

Front 3

Sterilization

Back 3

Sterilization-

Any process that completely removes or destroys all viable microorganisms, including viruses, from an object or habitat. Material so treated is sterile

Front 4

Bactericide

Back 4

Bactericide-

An agent that kills bacteria.

Front 5

Bacteriostatic

Back 5

Any process or agent that inhibits bacterial growth.

Front 6

Germicide

Back 6

Germicide-

An agent lethal to non-endosporeforming pathogens.

Front 7

Disinfection

Back 7

Disinfection-

The destruction of pathogenic nonsporulating microbes or their toxins, usually on inanimate surfaces.

Front 8

Sanitization

Back 8

Sanitization-

To clean inanimate objects using soap and degerming agents so that they are safe and free of high levels or microorganisms

Front 9

Autoclaves

Back 9

Autoclaves-

A sterilization chamber which allows the use of steam under pressure to sterilize materials.

(The most common temp/pressure combination for an autoclave is 121 degrees Celsius and 15 psi)

Front 10

Pasteurization

Back 10

Pasteurization-

(1) subjects liquids to temperatures below 100 degrees Celsius

(2) is used to LOWER the microbial load in liquids.

(3) Boiling water can used to destroy vegetative pathogens in the home.

Front 11

Incineration

Back 11

Incineration-

(1) Destruction of microbes by subjecting them to EXTREMES of DRY HEAT.

(2) Microbes are reduced to ashes and gas by this process.

Front 12

Desiccation-

Back 12

Desiccation (or Drying)-

leads to (often temporary) METABOLIC INHIBITION by reducing water in the cell.

Front 13

Radiation

Back 13

Radiation-

Electromagnetic waves or rays, such as those of light given off from an energy source.

Front 14

Ionizing Radiation

Back 14

Ionizing Radiation-

Radiant energy consisting of short-wave electromagnetic rays (X-rays) or high speed electrons that cause dislogment of electrons on target molecules and create ions.

Front 15

Non-ionizing radiation

Back 15

Non-Ionizing radiation-

Method of microbial control, best exemplified by ULTRAVIOLET LIGHT, that causes the formation of abnormal bonds within the DNA of microbes, increasing the rate of mutation.

LIMITATION: its inability to penetrate beyond the surface of an object.

Front 16

Ultraviolet

Back 16

Ultraviolet-

(1) Radiation with an effective wavelength from 240 nm to 260nm.

(2) UV radiation induces mutations readily, but has VERY POOR PENETRATING POWER.

Front 17

Antiseptics

Back 17

Antiseptics-

(1) A growth-inhibiting agent used on tissues to PREVENT INFECTION.

(2) Use of such an agent is "antisepsis"

Front 18

Sanitize

Back 18

Sanitize-

To CLEAN INANIMATE OBJECTS using soap and degerming agents so that they are safe and free of high levels of microorganisms.

Front 19

Degermers

Back 19

Degermers-

(1) To PHYSICALLY REMOVE surface oils, debris and soil from SKIN

(2) to REDUCE the microbial load.

Front 20

Aqueous

Back 20

Aqueous-

Water based

Front 21

Tinctures

Back 21

Tinctures-

alcohol based

Front 22

Halogens

Back 22

Halogens-

(1) are CHEMICALS based on elements from group VII of the periodic table with ANTIMICROBIAL APPLICATIONS.

(2) The halogens most often used in disinfectants and antiseptics are CHLORINE and IODINE.

Front 23

How does Chlorine work in microbial control?

Back 23

Chlorine-

(1) is used as chlorine gas, hypochlorites, and chloramines.

(2) Works by DISRUPTING disulfide bonds and, given adequate time, are SPORICIDAL.

Front 24

Iodophors

Back 24

Iodophors-

(1) Iodine bound to organic polymers such as soap

MODE OF ACTION: Similar to chlorine---also SPORICIDAL

(2) Is a moderate -level DISINFECTANT and ANTISEPTIC

Front 25

Surfactants

Back 25

Surfactants-

A surface-active agent that forms a water-soluble interface.

Ex: detergents, wetting agents, dispersing agents, and surface tension depressants.

Front 26

Phenolics

Back 26

Phenolics-

are CHEMICALS based on phenols

MODE OF ACTION: work by DISRUPTING cell membranes and precipitating proteins

CLASSIFICATION: bectericidal, fungicidal, and virucidal

***NOT SPORICIDAL

Front 27

Chlorhexidine

Back 27

Chlorhexidine-

is a SURFACTANT and protein denaturant with broad MICROBICIDAL properties.

APPLICATION: used as skin DEGERMING agents for preop scrubs, skin cleaning and burns.

***NOT SPORICIDAL

Front 28

Ethyl & Isopropyl alcohol

Back 28

Ethyl & Isopropyl Alcohol

Alcohols acts DISSOLVING membrane lipids and coagulating proteins of vegetative bacterial cells and fungi.

***NOT SPORICIDAL

Front 29

Hydrogen Peroxide

Back 29

Hydrogen Peroxide-

(1) produces highly reactive hydroxyl free radicals that DAMAGE protein and DNA

(2) also decomposes to O2 gas, which is toxic to ANAEROBES.

Strong solutions of H2O2 ARE SPORICIDAL.

Front 30

Aldehydes

Back 30

Aldehydes- (eg. glutaraldehyde and formaldehyde)

KILL microbes by ALKALIZING protein and DNA molectules

Front 31

Ethylene Oxide (ETO)

Back 31

Ethylene Oxide (ETO) (e.g. propelyene oxide, chlorine oxide)

A potent, highly WATER-SOLUBLE GAS invaluable for gaseous STERILIZATION of heat sensitive objects (e.g. plastics, surgical and diagnostic appliances)

STRONG ALKALIZING agents which ARE SPORICIDAL.

Front 32

QUATS

Back 32

Quats

A byword that pertains to a family of surfactants called quaternary ammonium compounds. These detergents are only WEAKLY MICROBICIDAL and are used a SANITIZERS and preservatives.

Front 33

Oligodynamic action

Back 33

Oligodynamic action

A CHEMICAL having antimicrobial activity in MINUSCULE amounts.

Ex: Solutions of silver and mercury kill vegetative cells (BUT NOT SPORES) in low concentrations.

-oligo = few, little

Front 34

A microbicidal agent has what effect?

a. sterilizes
b. inhibits microorganisms
c. is toxic to human cells
d. destroys microorganisms

Back 34

d. destroys microorganisms


(Textbook)

Front 35

Microbial control methods that kill _____ are able to sterilize.

a. viruses
b.the tubercle bacillus
c. endospores
d. cysts

Back 35

c. endospores


(Textbook)

Front 36

Any process that destroys the non-spore-forming contaminants on inanimate objects is

a. antisepsis
b.disinfection
c. sterilization
d. degeneration

Back 36

b. disinfection


(Textbook)

Front 37

Sanitization is a process by which

a. the microbial load on objects is reduced
b. objects are made sterile with chemicals
c. utensils are scrubbed
d. skins is debrided

Back 37

a. the microbial load on objects is reduced


(Textbook)

Front 38

An example of an agent that lowers the surface tensions of cells is

a. phenol
b. chlorine
c.alcohol
d.formalin

Back 38

c. alcohol


(Textbook)

Front 39

High temperatures_____and low temperatures ________

a. sterilize, disinfect
b. kill cells, inhibit growth
c. denature proteins, burst cells
d. speed up metabolism, slow down metabolism

Back 39

b. kill cells, inhibit growth


(Textbook)

Front 40

The primary action of _______heat is to _______

a. dry, destroy cell wall
b. moist, kill vegetative cells
c. dry, dissolve lipids
d. moist, denature proteins

Back 40

d. moist, denature proteins


****NOT a. dry, destroy cell wall
(Textbook)

Front 41

The temperature-pressure combination for an autoclave is

a. 100 degrees Celsius and 4psi
b. 121 degrees Celsius and 15 psi
c. 131 degrees Celsius and 9 psi
d. 115 degrees Celsius and 3 psi

Back 41

b. 121 degrees Celsius and 15 psi


(Textbook)

Front 42

Microbe(s) that is/are the target(s) of pasteurization include(s)

a. Clostridium Botulinum
b. Mycobacterium species
c. Salmonella species
d. both b and c

Back 42

d. both b and c


(Textbook)

Front 43

Ionizing radiation removes _______ from atoms.

a. protons
b. waves
c. electrons
d. ions

Back 43

c. electrons


(Textbook)

Front 44

The primary mode of action of nonionizing radiation is to

a. produce superoxide ions
b. make pyramidine dimers
c. denature proteins
d. break disulfide bonds

Back 44

b. make pyramidine dimers

***NOT (d) break disulfide bonds

(Textbook)

Front 45

The most versatile method of sterilizing heat-sensitive liquids is

a. UV radiation
b. exposure to ozone
c. beta propiolactone
d. filtration

Back 45

d. filtration

****NOT (a) UV radiation


(Textbook)

Front 46

______is the iodine antiseptic of choice for wound treatment.

a. eight percent tincture
b. five percent aqueous
c. iodophor
d. potassium iodide solution

Back 46

c. iodophor

***NOT (d) Potassium iodide solution

(Textbook)

Front 47

A chemical with sporicial properties is

a. phenol
b. alcohol
c. quaternary ammonium compound
d. glutaraldehyde

Back 47

d. glutaraldehyde


(textbook)

Front 48

Silver sulfadiazine is used

a. in antisepsis of burns
b. as a mouthwash
c. to treat genital gonorrhea
d. to disinfect water

Back 48

a. in antisepsis of burns

***NOT (d) to disinfect water

(Textbook)

Front 49

Detergents are

a. high-level germicides
b. low-level germicides
c. excellent antiseptics
d. used in disinfecting surgical instruments

Back 49

b. low-level germicides

***NOT (c) excellent antiseptics

(Textbook)

Front 50

Which of the following is an approved sterilant?

a. chlorhexidine
b. betadyne
c. ethylene oxide
d. ethyl alcohol

Back 50

c. ethylene oxide


(Textbook)

Front 51

Which of the following is not a method of microbial control used in ancient times?

a. Salting, smoking, pickling, and drying foods
b. Exposing food, clothing, and bedding to sunlight
c. Boiling drinking water
d. Consuming molds to derive antibiotic benefits
e. Burying human wastes

Back 51

d. Consuming molds to derive antibiotic benefits


(Online Quiz)

Front 52

Which of the following terms is defined as the destruction of vegetative pathogens but not bacterial endospores?

a. Disinfection
b. Antisepsis
c. Sterilization
d. Degermation
e. Microbicidal

Back 52

a. Disinfection

(Online Quiz)

Front 53

Of the microbial forms listed below, which exhibits the highest level of resistance to physical and chemical methods of growth control?

a. Protozoan cysts
b. Most vegetative bacterial cells
c. Bacterial endospores
d. Naked viruses
e. Yeasts

Back 53

c. Bacterial endospores


(Online Quiz)

Front 54

What is the goal of sterilization?

a. The destruction to protozoan trophozoites
b. The destruction of bacterial endospores
c. The destruction or inhibition of vegetative pathogens through chemicals applied to body surfaces
d. To temporarily inhibit the reproduction of microbes but not inflict irreversible damage
e. The destruction of fungal sexual spores (zygospores)

Back 54

b. The destruction of bacterial endospores


(Online Quiz)

Front 55

What term is defined as a chemical agent that is applied directly to body surfaces, wounds, and surgical incisions to destroy or inhibit vegetative pathogens?

a. Bacteriostatic agent
b. Fungicide
c. Disinfectant
d. Sanitizer
e. Antiseptic

Back 55

e. Antiseptic


(Online Quiz)

Front 56

Microbial death is defined as which of the following?

a. The permanent termination of an organism's vital processes
b. The permanent loss of reproductive capability, even under optimum growth conditions
c. The loss of movement in a motile microbe
d. Exposure to a chemical or physical agent for a period of time until a cell structure becomes dysfunctional
e Irreversible damage to a cell

Back 56

b. The permanent loss of reproductive capability, even under optimum growth conditions

***not--permanent termination of an organism's vital processes

(Online Quiz)

Front 57

Which of the following does not affect the action of antimicrobial agents?

a.Time
b. Temperature and pH of the environment
c. Presence of water
d. Number of microorganisms present
e. Mode of action of the agent

Back 57

c. Presence of water

**NOT (e) Mode of action of the agent

(Online Quiz)

Front 58

Physical and chemical antimicrobial agents can target all but which of the following?

a. Protein function
b. Cell membrane integrity
c. DNA replication
d. Capsule formation
e. Cell wall synthesis

Back 58

d. Capsule formation


(Online Quiz)

Front 59

Surfactants function as microbicidal agents because they do what to microorganisms?

a. Inhibit peptide bond formation during translation
b. Interfere with the synthesis of peptidoglycan
c. Prevent mRNA transcription
d. Denature proteins
e. Disrupt the integrity and lower the surface tension of cell membranes

Back 59

e. Disrupt the integrity and lower the surface tension of cell membranes

(Online Quiz)

Front 60

Agents that alter protein function may do all but which of the following?

a. Prevent peptide bond formation
b. Denature proteins
c. Coagulate proteins
d. Alter an enzyme's active site
e. Prevent an enzyme from interacting with its substrate

Back 60

a. Prevent peptide bond formation

**NOT
e. Prevent an enzyme from interacting with its substrate

(Online Quiz)

Front 61

Which of the following is not a concern that must be taken into consideration when selecting a method of microbial control?

a. The method must be suitable for the application
b. The method should not leave an undesirable residue behind
c. The method should be effective regardless of cost and labor effectiveness
d. The method should destroy only the microbial forms present
e. If the disinfected item is to be reused, it should be able to withstand the antimicrobial treatment

Back 61

c. The method should be effective regardless of cost and labor effectiveness

**NOT
b. The method should not leave an undesirable residue behind

(Online Quiz)

Front 62

What is the most widely used of the physical methods of microbial control?

a. Filtration
b. Heat
c. Radiation
d. Cold
e. Ultrasonic waves

Back 62

b. Heat


(Online Quiz)

Front 63

Common methods of using moist heat to control microbial growth include all but which of the following?

a. Incineration
b. Steam under pressure
c. Nonpressurized steam
d. Boiling water
e. Pasteurization

Back 63

a. Incineration


(Online Quiz)

Front 64

Pasteurization rids liquids of what microbial form?

a. Endospores
b. Thermoduric organisms
c. Nonpathogenic lactobacilli
d. Most viruses and vegetative stages of 97-99% of bacteria and fungi
e. Nonpathogenic micrococci

Back 64

d. Most viruses and vegetative stages of 97-99% of bacteria and fungi


(Online Quiz)

Front 65

Exposure to cold temperatures has what effect on microorganisms?

a. It removes moisture from the environment and thus prevents growth
b. It oxidizes and coagulates proteins
c.It retards the activities of most microbes
d. It denatures proteins
e. It kills endospores and thermophilic organisms

Back 65

c.It retards the activities of most microbes

NOT
**a. It removes moisture from the environment and thus prevents growth

(Online Quiz)

Front 66

Both ionizing and nonionizing radiation tend to effect what?

a. DNA
b. RNA
c. Cell membrane
d. Cell wall
e. Proteins

Back 66

a. DNA


(Online Quiz)

Front 67

Which of the following is not an effect of food irradiation?

a. It leads to a small decrease in the amount of vitamin B(sub)1(/sub) in food
b. It can kill bacterial pathogens that may exist in the food
c. It can kill insects and worms that live in or on the food
d. It can inhibit white potatoes from sprouting
e. It causes the formation of free-radical oxidants that remain in the food indefinitely

Back 67

e. It causes the formation of free-radical oxidants that remain in the food indefinitely

NOT
**d. It can inhibit white potatoes from sprouting

(Online Quiz)

Front 68

For what method of microbial growth control is the application of UV light useful?

a. Antisepsis
b. Sterilization
c. Bacteriostasis
d. Sanitization
e. Disinfection

Back 68

e. Disinfection


(Online Quiz)

Front 69

Which of the following effectively sterilizes plastic materials and surgical supplies?

a.Autoclave
b. Chlorine
c. Ethylene oxide
d. Dry heat
e. Soaps

Back 69

c. Ethylene oxide


(Online Quiz)

Front 70

Desirable qualities in a microbicidal chemical include all but which of the following?

a. Rapid action
b. Inexpensive
c. Inactivated by organic matter
d. Broad spectrum
e. Soluble in water or alcohol

Back 70

c. Inactivated by organic matter

NOT
** b. Inexpensive

(Online Quiz)

Front 71

Overuse of germicides is leading to all but which of the following problems?

a. Survival and growth advantages of resistant strains
b. Obsessive fear of "germs" among the general public
c. The selection of "supermicrobes"
d. Increased sensitivity of microbes to the phenolic triclosan
e. A reduction in natural contact with microbes required for maintenance of normal flora and for stimulation of immunity

Back 71

d. Increased sensitivity of microbes to the phenolic triclosan

NOT
**b. Obsessive fear of "germs" among the general public

(Online Quiz)

Front 72

Which of the following chemical agents is not sporicidal?

a. Alcohol
b. Hydrogen peroxide, stabilized
c. Glutaraldehyde
d. Ethylene oxide gas
e. Formaldehyde

Back 72

a. Alcohol

(Online Quiz)

Front 73

What germicidal chemical is used to prepare skin and mucous membranes for surgery and injections, is included in surgical handscrubs, is used to treat burns, and is used to disinfect equipment and surfaces?

a. Ethylene oxide gas
b. Formaldehyde
c. Phenolics
d. Glutaraldehyde
e. Iodine/iodophores

Back 73

e. Iodine/iodophores

(Online Quiz)

Front 74

Phenolics used for disinfection include all but which of the following?

a. Phenol
b. Chlorhexidine
c. Lysol
d. pHisoHex
e. Triclosan

Back 74

b. Chlorhexidine

NOT
**d. pHisoHex

(Online Quiz)

Front 75

What microbes were used in the senate's Hart office building to ensure that the fumigation and cleanup of Bacillus anthracis endospores was successful?

a. Escherichia coli
b. Staphylococcus aureus
c. Protozoan cysts
d. Bacillus stearothermophilus
e. Fungal spores

Back 75

d. Bacillus stearothermophilus

(Online Quiz)