Chapter 9 - Controlling Microbial Growth in the Environment

Question 1

Antisepsis

Answer 1

reduction in the number of microorganisms and viruses

Question 2

Aseptic

Answer 2

refers to an environment or procedure free of pathogenic contaminants

Question 3

Sanitization

Answer 3

removal of pathogens from objects to meet public health standards

Question 4

Sterilization

Answer 4

destruction of all microorganisms and viruses in or on an object

Question 5

Antimicrobial agents

Answer 5

alters cell walls and membranes, damages proteins and nucleic acids

Question 6

Most resistant microbes

Answer 6

prions, followed by mycobacteria

Question 7

High level germicides

Answer 7

kill all pathogens, including endospores

Question 8

Intermediate level germicides

Answer 8

kill fungal spores, protozoan cysts, viruses, pathogenic bacteria

Question 9

Low level germicides

Answer 9

kill vegetative bacteria, fungi protozoa, some viruses

Question 10

Methods for evaluating disinfectants and antiseptics

Answer 10

phenol coefficient, use-dilution test, Kelsey-Sykes capacity test, in-use test

Question 11

Heat-related methods for controlling microbes

Answer 11

moist heat and dry heat

Question 12

Moist heat

Answer 12

boiling, autoclaving, pasteurization, ultrahigh-temperature sterilization

Question 13

Autoclaving

Answer 13

121C, 15psi, for 15 min

Question 14

refrigeration

Answer 14

halts growth of most pathogens

Question 15

desiccation

Answer 15

drying inhibits growth because of removal of water

Question 16

osmotic pressure

Answer 16

high concentration of salt or sugar in foods to inhibit growth

Question 17

Ionizing radiation

Answer 17

shorter wavelengths

Question 18

nonionizing radiation

Answer 18

longer wavelengths, UV light

Question 19

Toughest bacterium

Answer 19

Deinococcus radiodurans

Question 20

Biosafety Level 1

Answer 20

do not cause disease in healthy humans

Question 21

Biosafety Level 2

Answer 21

moderately hazardous agents; gloves, mask, coat, sterilize, door closed

Question 22

Biosafety Level 3

Answer 22

safety cabinets; pathogenic, potentially fatal, double doors, treatment is available, transmitted through air

Question 23

Biosafety Level 4

Answer 23

pathogenic, no treatment, airborne

Question 24

phenols

Answer 24

intermediate to low level disinfectant

Question 25

alcohols

Answer 25

intermediate level disinfectants

Question 26

halogens

Answer 26

intermediate level disinfectant

Question 27

oxidizing agents

Answer 27

high level disinfectants

Question 28

aldehydes

Answer 28

high level disinfectants

Question 29

heavy metals

Answer 29

low level bacteriostatic