MICROBIAL CONTROL

Question 1

____ Heat Sterilization
This is applicable for substances unaffected at a
temperature of ___ºC to 260ºC in the oven, at
an exposure time of 45 minutes.

Answer 1

DRY
148

Question 2

Dry Heat Sterilization method kills ____, as well as _____ of microorganisms

Answer 2

spores, vegetative
forms

Question 3

Dry Heat Sterilization method is ideal for sterilizing

Answer 3

glasswares,
metalwares, and anhydrous oils

Question 4

Dry Heat Sterilization principle of sterilization involved is the
______ of microorganisms by heat.

Answer 4

oxidation

Question 5

used to sterilize inoculating
instruments by the use of alcohol lamp or
burner

Answer 5

Direct flaming

Question 6

burning materials to ashes

Answer 6

Incineration

Question 7

This is more effective than dry heat method.
The principle of sterilization is the coagulation of
the cell protein of the microorganism.

Answer 7

Moist Heat Sterilization

Question 8

It is the most effective method of moist heat
sterilization.

Answer 8

Autoclaving (steam under pressure)

Question 9

Autoclaving (steam under pressure) can destroy the

Answer 9

sporeformers.

Question 10

Autoclaving (steam under pressure) temperature used is ____ with a pressure
of ___ psi for 15-____ minutes exposure.

Answer 10

121ºC , 15 , 30

Question 11

Temperature used is 100ºC
Kills many vegetative cells and viruses within 10
minutes.

Answer 11

Boiling

Question 12

It uses a high temperature for a short time (__________) to destroy the pathogens
without altering the flavor of the food.

Answer 12

PASTEURIZATION 72ºC
for 15 seconds

Question 13

are effective for vegetative forms of
microorganisms, but not for spores

Answer 13

Fractional Sterilization Method

Question 14

It makes use of moist heat at 100 degrees
Celsius, using free flowing steam.
It is normally performed by 2 to 3 exposures,
alternated with intervals at room temperature or
incubator temperature.

Answer 14

Tyndallization

Question 15

Fractional Sterilization Method:

Answer 15

Tyndallization
Inspissation
Filtration
Cold
Desiccation
Osmotic pressure
Radiation

Question 16

It is a fractional method of sterilization
at 60 degrees Celsius in an oven, alternated
with intervals at room temperature or incubation
for 2 to 3 days

Answer 16

Inspissation

Question 17

Inspissation
It is a fractional method of sterilization
at___ degrees Celsius in an oven, alternated
with intervals at room temperature or incubation
for 2 to 3 _____.

Answer 17

60
days

Question 18

The passage of liquid or gas through a filter with
pores enough to retain microbes.

Answer 18

Filtration

Question 19

Membrane filters composed of _______are commonly used to filter
out bacteria, viruses and even large proteins.

Answer 19

nitrocellulose or
cellulose acetate

Question 20

The effectiveness of low temperatures depends
on the particular microorganisms and the
intensity of the application.
Microorganisms do not reproduce at ordinary
refrigerator temperatures (0º to 7ºC)

Answer 20

Cold

Question 21

In the absence of water, microorganisms cannot
grow but can remain viable.

Answer 21

Desiccation

Question 22

Viruses and endospores can resist

Answer 22

decolorization.

Question 23

Microorganisms in high concentrations of salts
and sugars undergo

Answer 23

plasmolysis

Question 24

Molds and yeasts are more capable of growing
in materials with____ moisture or ____ osmotic
pressure than bacteria are.

Answer 24

low, high

Question 25

This is used to aid reduction of air borne
contamination produced by mercury vapor
lamps.

Answer 25

Ultraviolet radiation

Question 26

Ultraviolet radiation
This is used to aid reduction of air borne
contamination produced by

Answer 26

mercury vapor
lamps

Question 27

Ultraviolet radiation method has poor penetration
capability. Its effectiveness depends on:

Answer 27

a. length of time of exposure
b. intensity of radiation
c. susceptibility of the microorganism

Question 28

This radiation method makes use of high
energy emitted from radioactive isotopes such
as cobalt 60 (gamma rays) or by cathode or
beta rays (mechanical acceleration of electrons
to high velocity and energy).

Answer 28

Ionization Radiation

Question 29

Ionization Radiation
This radiation method makes use of high
energy emitted from ______ such
as cobalt 60 (gamma rays) or by cathode or
beta rays (mechanical acceleration of electrons
to high velocity and energy).

Answer 29

radioactive isotopes

Question 30

are more reliable because there is
no mechanical breakdown, but it has a
disadvantage of rare source and cannot be shut
off immediately.

Answer 30

Gamma rays

Question 31

provide higher and more
uniform dose outfit and can destroy organisms
by stopping its reproduction.

Answer 31

Accelerated electrons

Question 32

Principles of Effective Disinfection

Answer 32

The presence of organic matter, degree of contact with microorganisms, and temperature should be considered.

Question 33

Evaluating a Disinfectant

Answer 33

In the filter paper method, a disk of filter paper
is soaked with a chemical and placed on an
inoculated agar plate; a clear zone of inhibition
indicates effectiveness.

Question 34

exert their action by injuring plasma
membranes, inactivating enzymes, and denaturing
proteins

Answer 34

Phenol and Phenolics

Question 35

Common phenolics are

Answer 35

cresols and
hexachlorophene

Question 36

damages plasma membranes of
vegetative cells.

Answer 36

Chlorhexidine

Question 37

are used
alone or as components of inorganic or organic
solutions.

Answer 37

Halogens

Question 38

Iodine is available as a _____ (in solution with
alcohol) or as an ______ (combined with an
organic molecule).

Answer 38

tincture

iodophor

Question 39

The germicidal action of chlorine is based on
the formation of _______ when
chlorine is added to water.

Answer 39

hypochlorous acid

Question 40

Chlorine is used as a disinfectant in gaseous
form (CI2) or in the form of a compound, such
as ______,______,_______.

Answer 40

calcium hypochlorite, sodium hypochlorite,
and chloramines

Question 41

Alcohols exert their action by _______
proteins and dissolving lipids.

Answer 41

DENATURATION

Question 42

Alcohols
In _____, they enhance the effectiveness of
other antimicrobial chemicals.

Answer 42

tinctures

Question 43

Aqueous ethanol (___% TO ___%) and isopropanol
are used as disinfectants.

Answer 43

60% to 90%

Question 44

are used as
germicidals.

Answer 44

Silver, mercury, copper, and zinc

Question 45

Heavy Metals and Their Compounds exert their antimicrobial action through

Answer 45

oligodynamic action

Question 46

decrease the tension
between molecules that lie on the surface of a
liquid; soaps and detergents are examples.

Answer 46

Surface-active agents

Question 47

have limited germicidal action but assist
in the removal of microorganisms through
scrubbing.

Answer 47

Soaps

Question 48

are used to clean dairy
equipment

Answer 48

Acid-anionic detergents

Question 49

By disrupting plasma membranes, they allow
cytoplasmic constituents to leak out of the cell

Answer 49

Quaternary Ammonium Compounds

Question 50

They are most effective against gram-positive
bacteria

Answer 50

Quaternary Ammonium Compounds

Question 51

inhibit fungal metabolism

Answer 51

Sorbic acid, benzoic acid, and propionic acid

Question 52

They are used as food preservatives.

Answer 52

Organic Acids and Derivatives: Sorbic acid, benzoic acid, and propionic acid

Question 53

They are among the most effective chemical
disinfectants.

Answer 53

formaldehyde and
glutaraldehyde

Question 54

is the gas most frequently used
for sterilization

Answer 54

Ethylene oxide

Question 55

It penetrates most material s and kills all
microorganisms by protein denaturation

Answer 55

Gaseous Chemosterilizers

Question 56

are used as antimicrobial
agents.

Answer 56

Ozone and peroxide

Question 57

They exert their effect by oxidizing molecules
inside cells

Answer 57

Oxidizing Agents