Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Medical Microbiology > Lecture 23 > Flashcards

Lecture 23 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
What are HEPA filters?
- high-efficiency particulate air filters - removes microbes > 0.3 micrometers in diameter
26
What do membrane filters remove?
microbes > 0.22 micrometers
27
What are some physical methods of microbial control?
- low temperature (refrigeration, deep freezing, lyophilization) - high pressure denatures proteins - desiccation: absence of water - osmotic pressure causes plasmolysis
28
What effect does low temperature have?
bacteriostatic effect
29
What is ionizing radiation?
x-rays, gamma rays, electron beams - ionizes water to create reactive hydroxyl radicals - damages DNA by causing lethal mutations
30
What is nonionizing radiation?
ultraviolet (260 nm) - damages DNA by creating thymine dimers
31
How do microwaves work?
kill by heat
32
What are principles of effective disinfection?
- concentration of disinfectant - organic matter - pH - time
33
What are dilution tests?
- 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
What is the disk-diffusion method?
- 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
What are biguanides for?
used in surgical hand scrubs - disrupts plasma membranes - chlorhexidine
36
What are essential oils?
- 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
What does iodine do?
impairs protein synthesis and alters membranes
38
What is tincture?
iodine solution in aqueous alcohol
39
What is iodophor?
iodine combined with organic molecules
40
What does chlorine do?
oxidizing agents - shut down cellular enzyme systems
41
What is bleach?
hypochlorous acid
42
What is chloramine?
chlorine + ammonia
43
What do alcohols do?
denatures proteins and dissolves lipids - no effect on endospores and nonenveloped viruses
44
How should ethanol and isopropanol be used?
mixed with water
45
What is oligodynamic action?
very small amounts exert antimicrobial activity
46
What do heavy metals do?
denature proteins
47
What is silver nitrate used for?
to prevents ophthalmia neonatorum
48
What does mercuric chloride do?
prevents mildew in paint
49
What is copper sulfate?
algicide
50
What is zinc chloride?
used in mouthwash
51
What does sulfur dioxide do?
prevents wine spoilage
52
What do organic acids do?
inhibits metabolism
53
What prevents molds in acidic foods?
- sorbic acid- benzoic acid - calcium propionate
54
What do nitrites and nitrates do?
prevents endospore germination
55
What do aldehydes do?
inactivated proteins by cross-linking with functional groups - used for preserving specimens and in medical equipment
56
What are examples of aldehydes?
- formaldehyde - ortho-phthalaldehyde - glutaraldehyde
57
What are peroxygens used for?
oxidizing agents - contaminated surfaces and food packaging
58
What are examples of peroxygens?
O3 H2O2 peracetic acid

Medical Microbiology (26 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions