Learning Objectives Study Guide Flashcards
1
Q
Who is responsible for the invention of the compound microscope
A
Zaccharias Janssen
2
Q
Define microphagia
A
fruiting body of molds
3
Q
What importance did Robert Hooke have on microbiology?
A
-first to report living things are composed to little boxes(cells)
-contributed to cell theory
-first known description of microorganisms
4
Q
What importance did Antonie van Leeuwenhoek have in microbiology?
A
first observed “animalcules” with self made microscope
5
Q
What two concepts did Pasteur provide?
A
-air is filled with microorganisms
-microorganisms come from other living microorganisms, thus disproving spontaneous generation
6
Q
What processes is Pasteur responsible for?
A
fermentation & pasteurization
7
Q
Define fermentation
A
microbial conversion of sugar to alcohol in the absence of air
8
Q
Define pasteurization
A
bacteria responsible for food spoilage is killed by heat
9
Q
What importance did Edward Jenner have in microbiology?
A
Jenner inoculated people with cowpox virus to protect against smallpox infection; aka vaccinations
10
Q
Compare spontaneous generation and biogenesis?
A
spontaneous generation hypothesizes that life arises from nonliving matter; biogenesis hypothesizes that living cells arise from preexisting living cells
11
Q
Define microbial genetics.
A
the study of how microbes inherit traits
12
Q
Define molecular biology.
A
studies how genetic information is carried in DNA molecules
13
Q
Define genomics
A
the study of an organism’s genes
14
Q
Define recombinant DNA
A
DNA from two different sources
15
Q
Define bacteriology
A
the study of bacteria
16
Q
Define mycology
A
the study of fungi
17
Q
Define parasitology
A
the study of protozoa
18
Q
Define immunology
A
the study of immunity and immune system
19
Q
Define virology
A
the study of viruses
20
Q
What kind of microscope has made it possible to study the structure of viruses in detail?
A
electron microscopes
21
Q
C. Woese proposed ______ ____ based on “_______ ______”
A
genetic tree; genetic tree
22
Q
Define phylogeny
A
history of evolutionary relationships among species or groups
23
Q
Light consists of ___________ ________ characterized by:
A
electromagnetic radiation; wave behavior; and particle(photon) energy
24
Q
Define wavelength
A
distance between peaks
25
Define amplitude
height of peak/depth of trough(light intensity)
26
Define frequency
vibration rate per unit of time
27
What role does electromagnetic radiation play in electron microscopy?
Electron microscopy uses electromagnetic coils(lenses) to guide electron beam
28
Describe images of electron microscopy
-always black and white
-may be colored artificially
29
How does transmission electron microscopy work?
electromagnetic coils(lenses) are used to form an image from electrons that have passed through a very thin section of specimen
30
When using a TEM, specimens must be _________.
dehydrated
31
Describe the view of a transmission electron microscope
-detailed ultrastructure of cells and viruses
-shadow casting to predict 3D shape
-Downside: very thin specimens, non-living specimens
32
In regard to energy, small wavelengths have _____ frequency, and _____ energy
high; high
33
In regard to energy, long wavelengths have _____ and ____ energy.
low; low
34
In regard to penetration, small wavelengths have _____ penetration
low
35
In regard to penetration, long wavelengths have _____ penetration
high
36
What is resolving power(resolution)?
ability to tell that two separate points or objects are separate
37
Resolution increases with ________ wavelength.
decreases
38
Resolution ________ with decreasing wavelength
increases
39
How does resolution affect image visibility?
allows you to distinguish details of a specimen
40
What is contrast?
difference in light intensity between image and adjacent background
41
What is the light source of a compound microscope?
visible light
42
What are the two lenses of a compound microscope?
objective and ocular
43
What is the image produced of a compound microscope?
optical replica that is formed by the refraction of light
44
How does a brightfield microscope form its image?
when light is directed at the specimen
45
What does the image of a brightfield microscope look like?
the specimen with appear darker than the surrounding bright illuminated field
46
What are chromophores?
pigments that absorb and reflect particular wavelengths of light
47
What kinds of specimens can brightfield microscopes observe?
live and preserved stained specimens with fair cellular detail
48
What is the purpose of the opaque light stop in a darkfield microscope
blocks light besides light reflecting off specimen
49
Describe the image observed through a darkfield microscope.
-brightly illuminated specimen surrounded by a dark field
-good outline but no internal structures
50
What kinds of specimen can darkfield microscopes use?
-live and unstained cells
51
Describe the image observed through a phase contrast microscope
halo around image
52
What is the light source of a phase contrast microscope?
light condenser
53
What kinds of specimens are able to be seen using a phase contrast microscope
-live and unstained cells
-internal cellular detail
54
What is the light source used in differential interference microscopy?
two beams of light; each a different polarization
55
Describe the image seen in differential interference contrast microscopy
image is slight colored and has a 3D appearance
56
What kinds of specimen can be used in differential interference contrast microscopy
-live & unstained cells
-thick specimens
-excellent for internal cellular detail
57
What light source is used in fluorescence microscopy?
additional UV light source
58
Describe the image seen in fluorescent microscopy.
bright, neon colors with black background
59
What is fluorescent microscopy good for?
-identification of pathogens
-able to see subcellular location of cellular structues
60
How does a scanning electron microscope work?
-electron gun produces a beam of electrons that scan the surface of specimen
-secondary electrons emitted from specimen are captured and recorded
61
What can scanning electron microscopes be used for?
-to study surface structures of intact cells and viruses
62
What kind of image does SEM produce?
-detailed surface structures of intact cells and viruses
-3D
63
What kinds of specimen can be seen through a SEM
dehydrated, non-living specimens
64
How does atomic force microscopy work?
probe scans the surface and transformed it into an image
65
Pro of AFM is
can map atomic and molecular shapes
66
Con of AFM is
non conducting examples
67
Why do we stain samples?
to increase the contrast
68
What is a chromophore ion?
colored ion
69
What is a counter ion?
uncolored ion
70
What is positive staining?
dye is absorbed by cells, adding color to cells in order to stand out against background
71
What is negative staining?
dye is absorbed by background but not cells
72
What is simple staining?
single dye used to color specimen
73
What is differential staining?
multiple dyes to distinguish multiple organisms
74
What color are gram positive cells?
purple
75
What color are gram negative cells
pink
76
What is acid fast staining used for?
to differentiate two types of gram positive cells
77
In endospore staining, endospores are _____, and vegetative cells are ______.
green, red
78
Prokaryotes consist of
archaea and bacteria
79
Eukaryotes consist of
fungi, protozoa, algae, other plants, and animals
80
What types of ribosomes do prokaryotes consist of?
70S
81
Where do eukaryotes contain their DNA
nucleus
82
What kind of cell walls do bacteria have?
peptidoglycan cell wall
83
What type of cell wall do archaea have?
pseudomurein cell wall and S layers
84
How do prokaryotes usually divide?
binary fission
85
What type of ribosomes do eukaryotes have?
80S
86
Eukaryotic cell division can be
mitosis or meiosis
87
Prefix for pair arrangement
diplo
88
Prefix for chain arrangement
strepto
89
Prefix for cluster arrangement
staphyo
90
Group of four arrangement
tetrads
91
Group of eight arrangement
sarcinae
92
Describe the S-layer
-outermost layer(if present)
-self assembly
93
What is the function of the S layer in archaea?
protection against osmotic lysis
94
What is the function of the S layer in bacteria
-exoskeleton
-contact w extracellular environment
95
Describe the capsule
organized tight structure and firmly attached to the cell wall
96
Describe the slime layer
diffused unorganized structure and loosely attached
97
What are the functions of capsules and slime layers?
-adhesion to surfaces
-protection
-prevention of phagocytosis
98
Slime layers facilitate ________ by gliding motility.
movement
99
Describe the cell wall.
-rigid yet flexible structure
100
Bacterial cell wall consists of
peptidoglycan
101
Cell wall of archaea consists of
-pseudopeptidoglycan
-S layers
102
What is peptidoglycan?
layers of meshwork of fabric
103
Gram positive have _____ peptidoglycan layers
thick (bc they have multiple peptidoglycan layers)
104
Gram negative have _____ peptidoglycan layer.
thin;
105
Describe the outer membrane of gram negative
-rich in lipopolysaccharides
-phospholipid bilayer
106
What is the function of the outer membrane of gram negative?
-acts as a barrier(dyes, metals, etc)
-strong negative charge
-porins
107
What do porins help do?
increase permeability to hydrophilic molecules
108
What is the structure of lipopolysaccharides?
1. lipid A
2. core polysaccharide
3. O-polysaccharide
109
What are the functions of lipopolysaccharides?
-structural part of OM
-provide neg. charge to OM
-Endotoxin(A): toxicity to animals
-recognized by immune system to initiate immune response
110
What do lysozymes do?
targets peptidoglycan
111
When does a protoplast occur?
when cell walls are destroyed(gram positive)
112
When does a spheroplast occur?
when cell walls are not completely destroyed(gram negative)
113
How to antibiotics interfere with cells?
interfere with cell wall synthesis
114
Which is more susceptible to antibiotics? Gram positive or gram negative
gram positive
115
In regard to osmoregulation, what does the cell wall do?
protects cell from changes in osmotic pressure
116
What is osmotic pressure?
pressure needed to stop the movement of water across the membrane
117
What is osmosis?
movement of water from areas of high to low concentration
118
Plasmolysis occurs when
the cell is hypertonic
119
Osmotic lysis occurs when
the cell is hypotonic
120
What is the fluid mosaic model?
lateral diffusion of phospholipids and proteins
121
What are hopanoids?
sterols that strengthen structure of membrane
122
What is the function of the cytoplasmic membrane?
1. selective barrier
2. secretion of material and waste
3. energy conservation
4. protein anchor
123
Passive process is
high to low concentration
124
Simple diffusion is
molecules and ions move until equilibrium is reached
125
What is facilitated diffusion?
substances are transporter proteins across membranes from high to low concentration
126
Active transport is
low to high concentration
127
What is primary active transport
requires energy in the form of ATP
128
What is secondary active transport?
transport against concentration gradient coupled to molecule transport down their conc. gradient
129
What is a symporter?
protein that moves two molecules in the same direction
130
What is an antiporter?
protein that moves two molecules in opposite directions
131
FtsZ refers to
microtubules
132
MreB refers to
microfilaments
133
CreS refers to
intermediate filaments
134
What is genophore?
bacterial chromosome
135
What do conjugative plasmids carry?
F factor
136
What do R plasmids carry?
antibiotic resistance genes
137
What are virulence plasmids?
virulence genes
138
Prokaryotes contain ___ ribosomes
70S
139
What is the composition of ribosomes?
ribosomal RNA and protein
140
What is the function of ribosomes?
protein synthesis
141
What is the structure of inclusions?
granule surrounded by liquid monolayer or protein shell
142
What is the function of inclusions?
substance storage and/or preserve cytoplasmic osmotic pressure
143
What are fimbria?
hairlike appendages
144
What is hami?
tiny grappling hooks
145
What are pili?
longer protein filaments(only in gram negative)
146
What is chemotaxis?
directed movement in response to chemicals
147
What is phototaxis?
directed movement in response to light
148
Define sporulation
endospore formation
149
What is endospore germination?
endospore returns to vegetative state
150
Endospore phases are
1. activation
2. germination
3. outgrowth
151
What is induced fit
enzyme may change its shape to fit better with substrate
152
Mechanisms for ATP production include:
1. substate level phosphorylation
2. oxidative phosphorylation
3. photophosphorylation
153
Define substrate level phosphorylation
a high energy phosphate is added to ADP; FERMENTATION
154
Define oxidative phosphorylation
energy released as electrons are passed to electron acceptors, and finally to O2; RESPIRATION
155
Define photophosphorylation
energy from light is trapped by chlorophyll, and electrons are passed through series of electron acceptors. Electron transfer releases energy used to ATP; PHOTOSYNTHESIS
156
Define chemiosmosis
proton motive force; aka moving ions to other side of biological membrane
157
Anabolism relies on _________ to build up complex molecules.
products of catabolism
158
Define mixotrophs
combination of multiple metabolic strategies
159
Define growth in micrbiology
increase in number, NOT cell size
160
What are the three stages of the cell cycle
1. cell elongation
2. DNA replication and septum formation
3. cytokinesis
161
Define biary fission
normal method of division, in which a single cell divides into two identical cells
162
The FtsZ right is
little ring formed between two splitting cells
163
The time required for a cell to divide or a population to double is
generation time
164
What is the order of microbial growth pattern
1. lag
2. exponential
3. stationary
4. death
165
Define inoculum
small numbers of starter cells
166
Persisters
slow metabolic rate
167
What is a chemostat?
open system used to maintain cell populations in exponential growth for extended periods
168
Define quorum sensing
explain development and behavior of biofilms
169
Define facultative anaerobe
aerobic organisms capable of living without oxygen if necessary
170
Define microaerophile
an aerobe that requires a small amount of oxygen bur does not grow under anaerobic conditions
171
Define obligate anaerobes
do not use free oxygen and cannot produce enzymes to dismantle reactive oxides
172
Define aerotolerant
anaerobe cannot use oxygen for respiration yet is not injured by it
173
Define osmophiles
microorganisms capable of living in habitats with a high solute concentration
174
Define halophiles
MO that thrive in high salt concentration
175
Describe barophiles
live in deep see trenches with high pressures(impossible to grow in lab)
176
Describe xerotolerant
able to grow in very dry environments
177
Define fomite
inanimate item that may contain and spread microbes(ie: doorknob)
178
Sterilization is
killing or removal of all microorganisms
179
Methods of inhibiting microbial growth on fomites include
disinfection and sanitization and sterilization
180
Methods of inhibiting microbial growth on living tissue include
antiseptic and degerming
181
Define disinfection
reduction of microbial load
182
Define sanitization
reduction of microbial load to safe public health levels
183
Define steriliation
kill all vegetative cells, endospores, and viruses
184
Define antiseptic
reduction of microbial load
185
Define degerming
reduction of microbial load with scrubbing and mild chemicals(ie: soap)
186
What affects does control of microbial growth have on cells?
-alteration of membrane permeability
-damage to proteins
-damage to nucleic acids
187
The decimal reduction time is(D value)
the time is takes for a protocol to yield a 90% reduction in microbial population
188
Thermal death time is
time it takes to kill all cells at a given temperature
189
Thermal death point is
lowest temperature at which all cells in a cliquid culture are killed in 10 min
190
How does moist heat kill
denatures proteins/enzymes
191
How does dry heat kill?
kills by oxidation
192
Alkylating agents...
modify DNA, causing failure in replication and protein
193
Surfactants
lipid solvent and disrupt cytoplasmic membrane
194
oxidizing agent
remove electrons from organic matter
195
What is the purpose of the efflux pumps
actively transport an antimicrobial drug out of the cell
196
