Brainscape's Knowledge GenomeTM

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


See full index

Medical Microbiology > Lecture 23 > Flashcards

Lecture 23 Flashcards

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

What is sepsis?

A

bacterial contamination

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

What is asepsis?

A

absence of significant contamination

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

Why do we use aseptic surgery techniques?

A

prevents microbial contamination of wounds

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

What is sterilization?

A

removing and destroying all microbial life

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

What is commercial sterilization?

A

killing Clostridium botulinum endospores from canned goods

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

What is disinfection?

A

destroying harmful microorganisms

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

What is antisepsis?

A

destroying harmful microorganisms from living tissue

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

What is degerming?

A

mechanical removal of microbes from a limited area

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

What is sanitization?

A

lowering microbial counts on eating utensils to safe levels

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

What is biocide?

A

germicide
- treatments that kill microbes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is bacteriostasis?

A

inhibiting, not killing, microbes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does the effectiveness of microbial treatment depend on?

A
  • number of microbes
  • environment
  • time of exposure
  • microbial characteristics
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the actions of microbial control agents?

A
  • alteration of membrane permeability
  • damage to proteins (enzymes)
  • damage to nucleic acids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How does heat affect enzymes?

A

heat denatures enzymes

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

What is thermal death point?

A

lowest temperature at which all cells in a liquid culture are killed in 10 minutes

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

What is thermal death time?

A

minimal time for all bacteria in a liquid culture to be killed at a particular temperature

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

What is decimal reduction time?

A

minutes to kill 90% of a specific population of bacteria at a given temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How does moist heat sterilization work?

A

-coagulates/denatures proteins
- steam from boiling or free-flowing steam
- large containers require longer sterilization times
- test strips indicate sterility

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

What is a common example of moist heat sterilization?

A

autoclave
- kills all organisms and endospores
- steam must contact item’s surface

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

What does pasteurization do?

A

reduces spoilage organisms and pathogens by heating materials for a short time

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

What are equivalent treatments for pasteurization?

A
  • high-temperature short time
  • ultra-high temperature
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is thermoduric?

A

relatively heat-resistant organisms survive

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

What is dry heat sterilization?

A

kills by oxidation
- flaming
- incineration
- hot-air sterilization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How does filtration work? Why is it used?

A

passage of substance through a screenlike material
- heat-sensitive materials

25
Q

What are HEPA filters?

A
  • high-efficiency particulate air filters
  • removes microbes > 0.3 micrometers in diameter
26
Q

What do membrane filters remove?

A

microbes > 0.22 micrometers

27
Q

What are some physical methods of microbial control?

A
  • low temperature (refrigeration, deep freezing, lyophilization)
  • high pressure denatures proteins
  • desiccation: absence of water
  • osmotic pressure causes plasmolysis
28
Q

What effect does low temperature have?

A

bacteriostatic effect

29
Q

What is ionizing radiation?

A

x-rays, gamma rays, electron beams
- ionizes water to create reactive hydroxyl radicals
- damages DNA by causing lethal mutations

30
Q

What is nonionizing radiation?

A

ultraviolet (260 nm)
- damages DNA by creating thymine dimers

31
Q

How do microwaves work?

A

kill by heat

32
Q

What are principles of effective disinfection?

A
  • concentration of disinfectant
  • organic matter
  • pH
  • time
33
Q

What are dilution tests?

A
  • metal cylinders are dipped in test bacteria and dried
  • placed in disinfectant
  • transferred to culture media to determine whether the bacteria survived or not
34
Q

What is the disk-diffusion method?

A
  • evaluates efficacy of chemical agents
  • filter paper disks are soaked in a chemical and placed on a culture
  • look for zone of inhibition around disks
35
Q

What are biguanides for?

A

used in surgical hand scrubs
- disrupts plasma membranes
- chlorhexidine

36
Q

What are essential oils?

A
  • mixtures of hydrocarbons extracted from plants
  • used in traditional medicine and for preserving food
  • microbial action due to phenolics and terpenes
  • stronger activity against gram-positive bacteria
37
Q

What does iodine do?

A

impairs protein synthesis and alters membranes

38
Q

What is tincture?

A

iodine solution in aqueous alcohol

39
Q

What is iodophor?

A

iodine combined with organic molecules

40
Q

What does chlorine do?

A

oxidizing agents
- shut down cellular enzyme systems

41
Q

What is bleach?

A

hypochlorous acid

42
Q

What is chloramine?

A

chlorine + ammonia

43
Q

What do alcohols do?

A

denatures proteins and dissolves lipids
- no effect on endospores and nonenveloped viruses

44
Q

How should ethanol and isopropanol be used?

A

mixed with water

45
Q

What is oligodynamic action?

A

very small amounts exert antimicrobial activity

46
Q

What do heavy metals do?

A

denature proteins

47
Q

What is silver nitrate used for?

A

to prevents ophthalmia neonatorum

48
Q

What does mercuric chloride do?

A

prevents mildew in paint

49
Q

What is copper sulfate?

A

algicide

50
Q

What is zinc chloride?

A

used in mouthwash

51
Q

What does sulfur dioxide do?

A

prevents wine spoilage

52
Q

What do organic acids do?

A

inhibits metabolism

53
Q

What prevents molds in acidic foods?

A
  • sorbic acid- benzoic acid
  • calcium propionate
54
Q

What do nitrites and nitrates do?

A

prevents endospore germination

55
Q

What do aldehydes do?

A

inactivated proteins by cross-linking with functional groups
- used for preserving specimens and in medical equipment

56
Q

What are examples of aldehydes?

A
  • formaldehyde
  • ortho-phthalaldehyde
  • glutaraldehyde
57
Q

What are peroxygens used for?

A

oxidizing agents
- contaminated surfaces and food packaging

58
Q

What are examples of peroxygens?

A

O3
H2O2
peracetic acid

Medical Microbiology (26 decks)

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