Quiz 1 Flashcards
Lab Lectures 2/19 - 3/5
1
Q
4 examples of aseptic technique
A
wash hands
disinfect bench
flame test tube
flame inoculating loop
2
Q
types of media
A
liquid
solid
3
Q
example of liquid media
A
broth in a test tube
4
Q
examples of solid media (3)
A
plates
slants
agar deeps
5
Q
what does agar originate from
A
marine algae
6
Q
function of agar
A
solidifying agent
7
Q
unique properties of agar (3)
A
most microbes can’t break it down
no nutrient value
liquefies at 100°C, stays liquid until 40°C
8
Q
at what temp (°C) does agar liquefy
A
100°C
9
Q
at what temp (°C) does agar solidify
A
40°C
10
Q
why is it called a compound brightfield microscope
A
compound = 2 lenses
brightfield = light passes through slide
11
Q
what are the names of the 2 lenses of the microscope
A
objective lense
ocular lens
12
Q
what are the 4 magnification options for the objective lens
A
4x
10x
40x
100x
13
Q
what is the magnification of the ocular lens
A
10x
14
Q
what is the equation to calculate total magnification
A
T.mag. = (mag. obj.) x (mag. ocu.)
15
Q
what is the total magnification when looking through the 4x objective lens
A
40x
16
Q
what is the total magnification when looking through the 10x objective lens
A
100x
17
Q
what is the total magnification when looking through the 40x objective lens
A
400x
18
Q
what is the total magnification when looking through the 100x objective lens
A
1000x
19
Q
what is magnification (of a microscope)
A
the size of the image
20
Q
what is resolution (of a microscope)
A
sharpness/clarity of an image
21
Q
what is parfocal (in a microscope)
A
still focused when you change objective lenses
22
Q
what is depth of field (of a microscope)
A
depth of an organism that can be seen
23
Q
what is refraction (of a microscope)
A
bending/scattering of light
24
Q
what is a working distance (of a microscope)
A
space between slide and objective lens
25
as magnification increases, resolution ___
decreases
26
as magnification increases, depth of field ___
decreases
27
as magnification increases, working distance ___
decreases
28
as refraction decreases, resolution ___
increases
29
what is a refractive index
measure of the bending power of a medium
30
what is the refractive index of glass
1.5
31
what is the refractive index of air
1
32
what is the refractive index of oil
1.5
33
what does adding oil to a slide do
reduces loss of light due to refraction
34
3 types of microbes
normal flora
pathogens
opportunistic pathogens
35
what are normal flora
organisms found in/on body
don't normally cause disease
36
2 types of normal flora
resident flora
transient flora
37
what is resident flora
colonize on body in symbiotic relationship
38
what is transient flora
on body for short period of time
don't colonize
39
what are pathogens
disease causing microbes
40
what are opportunistic pathogens
don't cause disease in healthy individuals
can be pathogenic under certain circumstances
41
example of opportunistic pathogens
candida albicans
42
what does candida albicans do
can cause yeast infections after antibiotic use
43
what is symbiosis
living together
44
types of symbiotic relationships
mutualism
commensalism
parasitism
45
what is mutualism
both benefit
46
example of mutualism
humans and gut microbes
47
what is commensalism
one benefits, other is unaffected
48
example of commensalism
skin microbes and humans
49
what is parasitism
one benefits, other is harmed
50
example of parasitism
any pathogen and humans
51
example of environmental microbes
extremophiles
52
what are extremophiles
microbes that live in extreme environments
53
ways to visualize bacteria
microscopy
culturing
54
culturing procedure
1) inoculate bacteria into medium
2) incubate medium
55
what is the clinical incubation temp
37°C
56
how long is medium incubated for
24-48 hours
57
how to read liquid media for growth
turbidity
58
how to read solid media for growth
solid growth
59
what is turbidity
cloudiness
60
2 types of cultures
mixed culture
pure culture
61
what is a mixed culture
contains >1 type of bacteria
62
what is a pure culture
contains 1 type of bacteria
63
how to make a pure culture
need isolated colonies
64
what is a colony
population of cells that arose from a single cell
65
methods of isolation (3)
streak plate
spread plate
pour plate
66
what is a streak plate
streak culture in 4-quadrant pattern onto agar plate
67
where do colonies form in a streak plate
on surface of the agar
68
is a streak plate quantitative
no
69
what is a spread plate
sample is diluted, then spread onto agar plate using spreading rod
70
where do colonies form in a spread plate
colonies form on surface of agar
71
is a spread plate quantitative
yes
72
what is a pour plate
sample is diluted, then added to empty plates; then melted agar poured into plates
73
where do colonies form in a pour plate
colonies form on the surface and on the inside of the agar
74
is a pour plate quantitative
yes
75
what are aerobes
microbes that utilize O2
76
2 types of aerobes
obligate aerobes
microaerophiles
77
what are obligate aerobes
require O2
78
what are microaerophiles
prefer vO2, ^CO2
79
what are anaerobes
don't utilize O2
80
3 types of anaerobes
obligate anaerobes
aerotolerant
facultative anaerobes
81
what are obligate anaerobes
cannot tolerate presence of O2
82
what are aerotolerant microbes
cannot utilize O2, but tolerate it fairly well
83
what are facultative anaerobes
capable of living w/ or w/o O2, but prefer it
84
why is thioglycolate broth helpful for culturing
areas w/ and w/o O2
85
components of thioglycolate broth
sodium thioglycolate
small amount of agar
resazurin
86
what does sodium thioglycolate do in thioglycolate broth
reducing agent
87
what does agar do in thioglycolate broth
reduces diffusion of O2 from air in tube
88
what does resazurin do in thioglycolate broth
O2 indicator
89
what color is resazurin when O2 is present
pink
90
what color is resazurin when O2 is absent
colorless
91
what is the type of microbe in test tube 1
obligate aerobe
92
what is the type of microbe in test tube 2
obligate anaerobe
93
what is the type of microbe in test tube 3
facultative anaerobe
94
what is the type of microbe in test tube 4
microaerophile
95
what is the type of microbe in test tube 5
aerotolerant
96
what is the purpose of an anaerobic pouch
creates anaerobic environment
97
what does a Gas Pak do
absorbs O2
produces CO2
98
what is the purpose of the methylene blue pill in the Gas Pak
O2 indicator
99
what color is the methylene blue pill when O2 is present
blue
100
what color is the methylene blue pill when O2 is absent
white
101
what is the purpose of the candle jar
creates microaerophilic environment by putting a lit candle into a jar
102
what does the candle do in the candle jar
candle flame consumes most of the O2 and produces CO2
103
what can staining bacteria reveal
size
morphology/shape
arrangement
104
3 shapes of bacteria
cocci
rods/bacilli
spiral
105
what is cocci shape
circles
106
what shape of bacteria is this
cocci
107
what is rods/bacilli shape
rods
108
what shape of bacteria is this
rods/bacilli
109
what is spiral shape
squiggly line
110
what shape of bacteria is this
spiral
111
5 types of arrangement
strepto
staphylo
diplo
tetrad
singular
112
what is a strepto arrangement
chains
113
what type of bacteria is this (shape + arrangement)
streptococci
114
what is a staphylo arrangement
grape-like clusters
115
what type of bacteria is this (shape + arrangement)
staphylococci
116
what is a diploid arrangement
2 cells
117
what type of bacteria is this (shape + arrangement)
diplococci
118
what is a tetrad arrangement
4 cells (2 on top, 2 on bottom)
119
what type of bacteria is this (shape + arrangement)
tetrad cocci
120
what is a singular arrangement
one cell
121
what color are bacteria in general
transparent
122
how do bacteria obtain color
use stains/dyes
123
what are stains
charged, colored ions in soln
124
what are cromophores
colored ions
125
what is the charge of a basic stain
positive charge on ions
126
example of a basic stain
methylene blue
127
what is the charge of an acidic stain
negative charge on ions
128
example of an acidic stain
nigrosin
129
what is the charge of bacteria
slightly negative
130
what do basic dyes stain
stain bacteria directly
131
what do acidic dyes stain
stain around bacteria
132
what is another name for a simple stain
direct stain
133
what is a simple stain
only one basic dye is used
134
what is a smear
thin film of bacteria on a slide
135
what is heat fixing
pass slide back and forth through bunsen burner flame 2x
136
what is the purpose of heat fixing (2)
- adheres bacteria to slide
- kills bacterial cell
137
are simple stains able to be stored
yes (heat fixed)
138
what is a negative stain
use an acidic dye
- bacteria left unstained and surrounded by dark background
139
procedure of negative stain
1) put drop of acidic dye at end of slide
2) aseptically add bacteria to drop of dye
3) push smear
140
what is a push smear
push a 2nd slide over dye/bacteria drop across the slide to spread it
141
are negative stains able to be stored
no (not heat fixed - live bacteria)
142
benefits to not heatfixing
bacteria morphology more accurate - not distorted by flame
143
what is a differential stain
use >1 stain
144
purpose of differential stain
allows us to differentiate between diff types of bacteria
145
what is a gram stain
used to differentiate between Gram-positive and Gram-negative bacteria
146
what is the bacterial cell wall made of
peptidoglycan
147
what is a carbohydrate backbone made of
repeating sugars NAG and NAM
148
what do glysosidic bonds link in the cell wall
NAG and NAM
149
what do peptide bonds link in the cell wall
carbohydrate backbones
150
gram-positive bacteria has a thick/thin layer of peptidoglycan
thick
151
gram-positive bacteria does/doesn't have teichoic acid
does
152
types of teichoic acid in gram-positive bacteria
wall teichoic acid
lipoteichoic acid
153
what is wall teichoic acid
connects peptidoglycan together
154
what is lipoteichoic acid
connects peptidoglycan to plasma membrane
155
gram-positive bacteria does/doesn't have an outer membrane
doesn't
156
gram-negative bacteria has a thick/thin layer of peptidoglycan
thin
157
gram-negative bacteria does/doesn't have teichoic acid
doesn't
158
gram-negative bacteria does/doesn't have an outer membrane
does
159
is this gram-negative or gram-positive bacteria
gram-positive
160
is this gram-negative or gram-postitive bacteria
gram-negative
161
what is the first reagent added in a gram stain
crystal violet
162
what is the second reagent added in a gram stain
gram's iodine
163
what is the third reagent added in a gram stain
acetone alcohol
164
what is the fourth reagent added in a gram stain
safranin
165
how long is crystal violet left to sit on the slide
~ 2 minutes
166
how long is gram's iodine left to sit on the slide
~ 2 minutes
167
how long is acetone alcohol left to sit on the slide
3-8 seconds
168
how long is safranin left to sit on the slide
~ 2 minutes
169
what is the function of crystal violet
primary stain
170
what is the function of gram's iodine
mordant (binding agent)
171
what is the function of acetone alcohol
destainer (decolorizing agent)
172
what is the function of safranin
secondary stain (counter-stain)
173
what colors are gram-positive and gram-negative bacteria after step 1, respectively
purple, purple
174
what colors are gram-positive and gram-negative bacteria after step 2, respectively
purple, purple
175
what colors are gram-positive and gram-negative bacteria after step 3, respectively
purple, colorless
176
what colors are gram-positive and gram-negative bacteria after step 4, respectively
purple, red/pink
177
what is the gram of the left side
gram-positive
178
what is the gram of the right side
gram-negative
179
3 ways to obtain inaccurate results for gram stain
1) destain for too long
2) destain for too short
3) cells too old
180
what happens if you destain for too long
gram-positive bacteria appear falsely gram-negative
181
what happens if you destain for too short
gram-negative bacteria appear falsely gram-positive
