Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Microbiology Unit 2 > Chemical & Physical Methods of Control (BE #3) > Flashcards

Chemical & Physical Methods of Control (BE #3) Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

disinfectant

A
  • reduces the # of pathogens to a level that poses no danger
  • used on inanimate objects
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

antiseptic

A
  • kills microbes or inhibits growth

- used on skin or living tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

microbiocidal

A

treatment that kills molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

microbiostatic

A

treatment that inhibits, rather than kills, microbes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

sterilization

A

destroys all microbial life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

commercial sterilization

A

food subjected to just enough heat to destroy Clostridium botulinum spores

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

2 advantages to using heat to control microbes

A
  • simple

- inexpensive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the mode of action of heat?

A

denatures proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is disadvantage to boiling?

A

doesn’t kill thermophiles or endospores; can change the flavor of some foods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Conditions for autoclaving

A

15-20 min, 15 psi, 121 degrees C

  • the pressure raises the temp to above boiling
  • disadvantage - can’t use with heat sensitive materials
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the advantage of pasteurization?

A

doesn’t change the taste/appearance of food

  • used in dairy products, wine, beer, “egg beaters”
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the effect of using cold to control microbes?

A

microbiostatic - does not sterilize

MOA - slows down metabolic rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

2 types of radiation that kill bacteria & their mode of action

A

nonionizing (UV) & ionizing (x-rays, gamma rays)

MOA - mutates DNA

Sterilizes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the disadvantages of using UV light?

A

only kills on surfaces (doesn’t penetrate) & can be harmful to humans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

2 types of ionizing radiation

Disadvantage to using this type?

How is it being used?

A

X-rays
gamma rays
MOA - strip electrons from atoms, which causes free radicals to form that damage other molecules in the cell, such as DNA

technically complex

meat, produce, grains, spices, poultry

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why is filtration replacing pasteurization in some cases?

A

causes even less damage to heat sensitive materials.

Used with antibiotics, beer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are some microorganisms that can pass through a filter?

A
  1. Mycoplasma - no cell wall so can squeeze through small spaces
  2. spirochetes - corkscrew their way through small holes
  3. viruses - too small to stop
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is lyophilization?

A

freeze drying - materials are frozen & then the ice is turned to a gas.

Advantage - avoids chemical changes caused by heat drying
MOA - slows down metabolic rate;
Disadvantage - expensive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

MOA of using high concentrations of salt or sugar?

A

creates a hypertonic environment & “sucks” the water out of bacterial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

2 test organisms traditionally used to test germicides

A

Salmonella typhi

Staphylococcus aureus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

disadvantage to using alcohol

A

evaporates quickly
doesn’t kill endospores
not good for wound treatment (causes coagulation of proteins, under which microbes can grow)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

why is Staphylococcus relatively resistant to hydrogen peroxide (H2O2)?

A

Staph produces catalase & peroxidase, which H2O2 reacts with and turns to H2O & O2.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is MOA of surfactants?

A

Penetrates oily substances in water & breaks them apart into small droplets that become coated with surfactant molecules. The hydrophobic end of the surfactant sticks into the droplets & the hydrophilic end is attracted to the water. The result is an emulsion, a fine suspension of oily droplets in water, which can now be rinsed away.

24
Q

Advantage & disadvantage to using alkylating agents

A

advantage - they sterilize

disadvantage - carcinogenic

25
Q

2 chemical preservatives added to commercially prepared foods

A
  1. calcium propionate
  2. sorbic acid
  3. sodium benzoate
  4. sodium nitrate (& nitrite)
26
Q

why is chloramine considered more effective than chlorine for the disinfection of drinking water?

A

it’s more stable & doesn’t react with organic material (blood, vomit)

27
Q

why would alcohol gel be preferred to antimicrobial soap for hand washing by healthcare professionals?

A
  • no bacterial resistance
  • quicker to use
  • less drying than soap
  • works well in presence of blood
28
Q

cresol

A

a phenolic from the greasewood bush used to prevent the rotting of wooden posts, fences, railroad ties, etc.

29
Q

hexachlorophene

A

a chlorinated phenol; used in soaps & lotions (Physohex); now known to increase risk of brain damage in babies

30
Q

iodophor

A

a halogen; a mixture of iodine & surfactants; used for surgical scrubs and to disinfect skin before surgery

31
Q

ethanol

A

an alcohol; widely used as skin antiseptic; a 50-70% solution in water is the most effective

32
Q

soaps/detergents

A

surfactants

wash away microbes, but don’t kill them

33
Q

hydrogen peroxide

A

used as an antiseptic & disinfectant

bubbles when it comes in contact with tissue

34
Q

iodine tincture

A

a halogen
a mixture of iodine & alcohol
used as an antiseptic

35
Q

formalin

A

alkylating agent
used to preserve tissues & to embalm
low concentrations are used to inactivate microbes for vaccines

36
Q

chlorine (Chlorox)

A

a halogen
household bleach
added to drinking water & swimming pools

37
Q

lysol

A

a phenolic
common ingredient in household & hospital disinfectants
remains active in the presence of blood & feces

38
Q

ethylene oxide

A

alkylating agent
gas
used to sterilize heat sensitive materials
toxic to humans

39
Q

silver nitrate

A

heavy metal

applied to newborn’s eyes to prevent gonorrhea

40
Q

merthiolate

A

heavy metal containing mercury
antiseptic
basic first aid kit supplies
contains thimerosal

41
Q

quats

A

surfactant
widely used as antiseptic for skin, mucous membranes & wounds; preop prep of skin, surgeon’s hands/arms
don’t kill spores
effectiveness decreased in presence of soap
supports Pseudomonas growth

42
Q

wetting agent

A

a surfactant added to another chemical agent to help them penetrate fatty substances

43
Q

selenium sulfide

A

heavy metal used to treat fungal skin infections

included in dandruff shampoos

44
Q

crystal violet

A 
also known as gentian violet; blocks cell wall synthesis
inhibits G(+) bacteria & yeasts
45
Q

betadine/isodine

A

a halogen
a mixture of iodine & surfactants
used for surgical scubs & to disinfect skin before surgery

46
Q

zephiran/cepacol/bactine

A

surfactant
widely used
effectiveness decreased in presence of soap
supports Pseudomonas growth

47
Q

triclosan

A

phenol used in many antibacterial soaps & cutting boards

48
Q

chlorhexidine

A

biguanide
used in mouthwashes, surgical hand scrubs, skin creams
to teat gum disease (Peridex, Perioguard, Periochip)
interferes with Vit. K absorption
teeth staining occurs when taking iron

49
Q

chloramines

A

now used by water treatment facilities to disinfect drinking water

50
Q

copper sulfate

A

heavy metal used as a fungicide on crops & produce;

used as an algaecide & a molluscicide

51
Q

sodium nitrate

A

prevents germination of Clostridium botulinum spores in meats

52
Q

mercurochrome

A 
heavy metal containing mercury
antiseptic
"monkey blood"
now banned by FDA
now contain quits instead
53
Q

thimerosal

A

heavy metal containing mercury
found in merthiolate
also used as a vaccine preservative & in cosmetics, nasal sprays, etc.

54
Q

povidone-iodine (PVP iodine)

A

a halogen
mixture of iodine & surfactants
used for surgical scrubs and to disinfect skin before surgery

55
Q

PCMX (nanotechnology)

A

charged nano spheres of oil droplets

disrupt cell envelope

56
Q

What are advantages of using PCMX (nanotechnology)

A

non-corrosive
non-irritating
kills quickly
doesn’t require EPA handling, warning or precaution
works well as Quats & chlorine-based products

Microbiology Unit 2 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions