CHAPTER 9

Question 1

the eradication of microorganisms and viruses; the term is not usually applied to the destruction of prions.

Answer 1

sterilization

Question 2

environment or procedure is free of contamination by pathogens

Answer 2

aseptic

Question 3

the inhibition/killing of microorganisms (particularly pathogens) on skin or tissue by the use of a chemical antiseptic

Answer 3

Antisepsis

Question 4

refers to the use of agents (called disinfectants) to inhibit microbes on inanimate objects.

Answer 4

Disinfection

Question 5

refers to the removal of microbes from a surface by scrubbing.

Answer 5

degerming

Question 6

the reduction of a prescribed number of pathogens from surfaces and utensils in public settings.

Answer 6

Sanitization

Question 7

process using heat to kill pathogens and con- trol microbes that cause spoilage of food and beverages.

Answer 7

Pasteurization

Question 8

This suffix indicates that an antimicrobial agent inhibits microbes

Answer 8

Stasis and static

Question 9

This suffix indicates that the agent kills or permanently inactivates a particular type of microbe.

Answer 9

Cide and tidal

Question 10

permanent loss of reproductive capacity.

Answer 10

Microbial death

Question 11

measures the efficacy of an antimicrobial agent.

Answer 11

Microbial death rate

Question 12

Antimicrobial agents destroy microbes either by

Answer 12

Altering their cell walls and membranes or by interrupting their metabolism and reproduction

Question 13

Factors affecting the efficacy of antimicrobial methods include

Answer 13

site to be treated, the relative susceptibility of microorganisms, and environmental conditions.

Question 14

lowest temperature that kills all cells in a broth in 10 minutes

Answer 14

Thermal death point

Question 15

the time it takes to completely sterilize a particular volume of liquid at a set temperature

Answer 15

Thermal death time

Question 16

the time required to destroy 90% of the microbes in a sample.

Answer 16

Decimal reduction time

Question 17

uses steam heat under pressure to sterilize chemicals and objects that can tolerate moist heat.

Answer 17

Autoclave

Question 18

Methods of pasteurization

Answer 18

the historical (batch) method, flash pasteurization, and
ultra-high-temperature pasteurization.

Question 19

Under certain circumstances, microbes can be controlled using

Answer 19

ultra-high-temperature sterilization, dry-heat sterilization, incin- eration, refrigeration, or freezing.

Question 20

Antimicrobial methods involving drying are _, used to preserve food

Answer 20

Desiccation

Question 21

used for the long-term preservation of cells or microbes.

Answer 21

Lyophilization( freeze- drying)

Question 22

the passage of air or a liquid through a material that traps and removes microbes.

Answer 22

Filtration

Question 23

have pores small enough to trap the smallest viruses.

Answer 23

Membrane filters

Question 24

What is the meaning of HEPA

Answer 24

High-efficiency particulate air

Question 25

exerted by hypertonic solutions of salt or sugar can preserve foods such as jerky and jams by removing from microbes the water that they need to carry out their meta- bolic functions.

Answer 25

High osmotic pressure

Question 26

includes high-speed subatomic particles and even more energetic electromagnetic waves released from atoms.

Answer 26

Radiation

Question 27

(wavelengths shorter than 1 nm) produces ions that denature important molecules and kill cells.

Answer 27

Ionizing radiation

Question 28

(wavelengths longer than 1 nm) is less effective in microbial control, although UV light causes pyrimidine dimers, which can kill affected cells.

Answer 28

Nonionining radiation

Question 29

are chemically modified phenol molecules, are intermediate- to low-level disinfectants that denature proteins and disrupt cell membranes in a wide variety of pathogens.

Answer 29

Phenolics

Question 30

intermediate-level disinfectants that denature pro- teins and disrupt cell membranes; they are used either as 70% to 90% aqueous solutions or in a tincture, which is a combination of an alcohol and another antimicrobial chemical.

Answer 30

Alcohols

Question 31

(iodine, chlorine, bromine, and fluorine) are used as intermediate-level disinfectants and antiseptics to kill microbes by protein denaturation in water or on medical instruments or skin.

Answer 31

Halogens

Question 32

such as hydrogen peroxide, ozone, and per- acetic acid are high-level disinfectants and antiseptics that release oxygen radicals, which are toxic to many microbes, especially anaerobes.

Answer 32

Oxidizing agents

Question 33

include soaps, which act primarily to break up oils during degerming

Answer 33

Surfactants

Question 34

such as quaternary ammo- nium compounds (quats), which are low-level disinfectants.

Answer 34

Detergents

Question 35

such as ions of arsenic, silver, mercury, copper, and zinc, are low-level disinfectants that denature proteins. For most applications they have been superseded by less toxic alternatives.

Answer 35

Heavy metal ions

Question 36

are high-level disinfectants that cross-link organic functional groups in proteins and nucleic acids. A 2% solution of glutaraldehyde or a 37% aqueous solution of formaldehyde (called formalin) is used to disinfect or sterilize medical or dental equipment and in embalming fluid.

Answer 36

Aldehydes

Question 37

Many organisms use __ to combat microbes. Humans use them commercially in food preservation and as a

Answer 37

Antimicrobial enzymes

Question 38

include antibiotics, semisynthet- ics, and synthetics, are compounds that are typically used to treat diseases but can also function as intermediate-level disinfectants.

Answer 38

Anti microbial drugs

Question 39

Four methods for evaluating the effectiveness of a disinfectant or antiseptic are the

Answer 39

phenol coefficient, the use-dilution test, the Kelsey-Sykes capacity test, and the in-use test.