Chapter 9

Question 1

Disinfection

Answer 1

physical process or a chemical agent to destroy vegetative pathogens but not bacterial endospores. removes. harmful products of microorganisms

Question 2

sterilization

Answer 2

process that destroys. or removes all viable microorganisms including viruses

Question 3

antisepsis

Answer 3

reduces the number of microbes on the human skin. a form of decontamination but on living tissues

Question 4

sanitation

Answer 4

cleansing technique that mechanically removes microorganisms as well as other debris to reduce contamination to safe levels

Question 5

cide

Answer 5

to kill

Question 6

static

Answer 6

to stand still, no replication but still alive

Question 7

2 most resistant

Answer 7

Prions and bacterial endospores

Question 8

understand the mechanisms of killing bacteria

Answer 8

1. damage the cell wall
2. change cell membrane permeability
3. damage cell synthesis
4. damage protein

Question 9

moist vs dry heat

Answer 9

moist heat is faster at sterilizing than dry heat is

Question 10

autoclaving

Answer 10

using high pressure steam to sterilize. most efficient is 15 PSI which yields 121 degrees celcius for 15 minutes

Question 11

pasteruization

Answer 11

heat is applied to liquids to kill potential agents of infection and spoilage, lowers the overall numbers. does not kill endospores

Question 12

boiling

Answer 12

for disinfection, expose materials to boiling water for 30 minutes.

Question 13

baking in the oven

Answer 13

used for heat resistant items that do not sterilize well with moist heat

Question 14

ionizing radiation

Answer 14

gamma rays, x rays, and cathode rays. energy. emitted from atomic activities and dispersed at high velocity through matter or space.

Question 15

UV

Answer 15

not as penetrating doesn’t kill spores.

Question 16

filtration how it works

Answer 16

effective for removing microbes from air and liquids

Question 17

filtration liquid

Answer 17

filters. are usually thin membranes of cellulose acetate. water purification can be done

Question 18

halogen

Answer 18

halogens denature proteins and inactivate enzymes. safe on people

Question 19

phenol

Answer 19

high concentrations: denaturation of the bacterial proteins and lysis of the cell membrane
lower concentrations: inactivate certain critical enzyme systems

Question 20

chlorohexadine

Answer 20

safe on people and surfaces. denatures cell membranes and disrupts protein structure

Question 21

alcohols

Answer 21

mechanism of action depends on concentration

Question 22

hydrogen peroxide

Answer 22

germicidal effects are due to the direct and indirect action of oxygen. safe on humans

Question 23

detergents

Answer 23

act as surfactants. positively charged end binds well with the predominantly negatively charged bacterial surface proteins

Question 24

heavy metals

Answer 24

bind functional groups of proteins and inactivates them. toxic to humans

Question 25

aldehydes

Answer 25

Disinfectants not used on humans

Question 26

ethylene oxide (gaseous)

Answer 26

used to sterilize heat. sensitive items

Question 27

hydrogen peroxide (gaseous)

Answer 27

plasma sterilizers

Question 28

dyes

Answer 28

primary source of certain drugs used in chemotherapy, we don’t use on people but we could.