prelim 1 Flashcards
1
Q
Prokaryotes and Eukaryotes
A
Body is a habitat for
2
Q
Domains
A
What lives on and in your body?
3
Q
C, O, N, H, P and S
A
What are atoms made of?
4
Q
Atoms
A
What are molecules made of?
5
Q
Large complex molecules
A
What are macromolecules made of?
6
Q
H20, H2, CH4, NH3
A
What is Earth’s early atmosphere?
7
Q
Inorganic compounds
A
Organization of what into organic life forms Earth’s atmosphere
8
Q
Amino acids/other organic compounds
A
Miller-Urey Experiment produced what with electricity
9
Q
Molecules that make up proteins
A
What are amino acids
10
Q
R
A
What symbol are amino acids?
11
Q
Molecules that made up nucleic acids?
A
What are nucleotides?
12
Q
Pentose sugar, phosphate group, nitrogenous base
A
What are nucleotides made of?
13
Q
20 different types (polypeptides)
A
What do amino acids organize themself into
14
Q
4-5 different types (polynucleotides)
A
What do nucleotides organize themself into
15
Q
Macromolecules
A
There chains of molecules form what
16
Q
Polynucleotides
A
Make copies of themselves
17
Q
Complementarity
A
How do they self-replicate
18
Q
Nucleotides
A
Bind to one nucleotide more than others
19
Q
Lipids
A
Form contained structures when in water
20
Q
Central Dogma
A
Genetic flow of information in the cell (DNA replication, RNA synthesis transcribes, protein synthesis translates)
21
Q
DNA
A
much more stable than RNA
22
Q
Tree of life
A
Show relationships in evolution based on shared characteristic
23
Q
Divide between Bacteria/(Archaea&Eukarya)
A
Last common ancestor of today’s species
24
Q
MOST IMPORTANT
A
- Inorganic molecules form organic molecules under right conditions, 2. Enclosure of nucleic acids and protins in lipid shells may be precursors of life, 3. All life on Earth falls into three domains of the tree of life
25
Hair follicles
Zits form where
26
Sebaceous gland
What produces oil, blocking duct into follicle
27
Propionibacterium acnes
Blockage leads to infection by what
28
Bacterium
What is propionibacterium acnes?
29
Anaerobic environments (no oxygen)
Where do propionibacterium acnes occur?
30
Last universal common ancestor
LUCA
31
Bacteria + Archaea
What domains are enormously abundant
32
Cocci (spherical), bacilli (rod-shaped), and spirilla (spiral)
Shapes of bacteria and archaea
33
Squares, stars, filaments
Other shapes of bacteria and archaea
34
Rod-shaped
Propionobacterium acnes is what shape
35
Oil (chemoheterotroph)
What does pripionobacterium acnes eat for energy?
36
Cell membrane + cell wall together
What makes an envelope?
37
Bilipid layer of phospholipids (micelles)
What makes cell membrane?
38
Peptidoglycan
Cell wall
39
Gram-positive and gram-negative
What types can cell envelopes come in?
40
Staining process used to determine permeability
What is a gram
41
Components of cell wall/membrane can be targeted by antibiotics
Why is gram important?
42
Blue/purple
What color is gram positive
43
Red/pink
What color is gram negative
44
Gram-positive
What color is propionobacterium acnes?
45
Malassezia spp.
What may cause dandruff
46
Sebum(oil/lipids) and carbon (chemoorganotroph)
What does Malassezia consume for energy?
47
Skin surface
Where does Malassezia occur?
48
Unsaturated fatty acids, penetrating skin
The consumption of lipids results in what
49
A eukarya (fungi?)
What domain is Malassezia spp.
50
Bacteria + Archaea
Do not have nucleus/other organelles
51
Typically circular
Bacteria + Archaea DNA shape
52
Organelles
Act as active site for respiration/photosynthesis
53
Endosymbiosis of bacteria in archaea
Where did organelles come from?
54
Membrane-bound organelles of eukaryotes
What did endosymbiosis result in
55
Eukarya
Archaea more closely related to
56
MOST IMPORTANT
1. Acne is caused by infction with bacteria Propionibacterium acnes, 2. Dandruff is dead skin that can increase from scalp irritation caused by fungi Malassezia
57
Metazoans (contain more than one cell, usually differentiated tissues)
What are head lice
58
Obligate parasites
What are head lice to humans
59
Vectores, have symbionts
What are they of microorganisms
60
MOST IMPORTANT
1. Eukaryotes evolved through symbiosis between tow microorganisms, 2. Metazoans are one branch of many in tree of eukaryotes, 3. Parasites are symbionts, but not all symbionts are parasites
61
Ectosymbiosis
When one species lives on or near another species
62
Endosymbiosis
When one species lives inside another
63
Larger species
Host
64
Smaller species
Symbiont
65
Mutualistic
All partners benefit
66
Commensalism
One partner benefits while other is unharmed
67
Parasitic
One partner benefits while other is hurt
68
Obligate
Symbiosis is necessary for survival (ex. Dracunulus medinesis)
69
Facultative
Symbiosis is opportunistic and symbiont/host can exist without other partner (ex. Naeegleria fowleri)
70
Mitochondria
Derived from a bacterium
71
Symbiont became dependent on host, lost most genes, then host evolved linear chromosomes, fusion resulted
Why is symbiosis important for evolution?
72
Mitochondria and chloroplasts
Have double membranes (have original membranes and obtained another from host)
73
Have large number of other pathogens within body, but pathogenic to humans
Head lice are...
74
Pediculus humanus
Name of lice
75
Arthropod
What are head lice species
76
Human-human contact
Vectored how?
77
Pyrethrins
How to treat lice
78
Delay closure of voltage channels in nerves
What do pyrethrins do
79
Blood-borne diseases
What can head lice transmit
80
Epidemic typhus
Bacterium Rickettsia prowazekii
81
Relapsing fever
Bacterium Borrelia recurrentis
82
Trench fever
Bacterium Bartonella quintana
83
Bartonella quintana
Head lice are a vector for
84
Aerobic gram negative, picky about cell culture conditions, grow best with human blood, may exist in arthropods but grows best in humans, not a symbiont
Facts about Bartonella quintana
85
Have endosymbiotic bacteria
Because blood lacks nutritional requirmeents, as can only be made by some bacteria, lice have ... to make these compounds
86
Hosts
What are head lice in a mutualistic endosymbiosis
87
A mutualistic relationship
What is endosymbiosis with the bacterium Riesia spp
88
Low
Lice can survive but have what chance of success
89
Riesia has no genes for energy metabolish, gets nutrients from host
Why is symbiosis important for evolution?
90
Microbiome
Where is this common
91
Pthiris pubis
Crabs name (pubic lice)
92
MOST IMPORTANT
1. Mutualistic endosymbiosis result in loss of genetic capability to live independently, 2. Eukaryotes arose through endosymbiosis where relationship became obligate, 3. Some bacteria amy be widspread in metazoan but may not be symbiont, 4. Pathogenic bacteria may be vectored from host to host
93
Bacteria
Dental plaque caused by ... in mouth
94
Reduced chemical compounds
Stink is caused by
95
MOST IMPORTANT
1. Bacteria use catabolic reactions to capture energy which is then used in anabolism, 2. Reaction carried out by enzymes encoded for by genes, 3. Some interactions are pathogenic resulting in degradation by enzyme activities
96
Lots of habitats for microorganisms bc moist/warm
Description of oral cavity
97
Dead mucose, ingested material, egested material
Resources for microorganisms
98
[Oral] Microbiome
Most microorganisms do not cause disease (not pathogens)
99
Thick cell wall
What type of cell wall does gram positive have
100
Thin cell wall/outer membrane
What type of cell wall does gram negative have
101
Oxygen comes into direct contact w/ surfaces
Aerobic habitats
102
No oxygen contact, under biofilms, back of tongue
Anaerobic habitats
103
Anaerobic reactions
Stinky compounds are reduced compounds produced in
104
Metabolism/catabolism
What is stinky compound formation part of
105
Inflammation of gums
Gingivitis
106
Gram negative bacterium Porphyromonas endodontalis
How is gingivitis caused
107
Anaerobic bacterium
What is P. endodontalis
108
Methyl mercaptan
What does P. endodontalis make
109
Electrons (chemical bonds)
Where does energy come from
110
Gain of electrons
Reduction
111
Loss of electrons
Oxidation
112
ATP (Adenosine triphosphate)
How do living cells store energy?
113
Three phosphate-oxygen double bonds
Describe ATP
114
Energy producing and energy consuming reactions
ATP is key to
115
Glogogen (sugar polymer), starch, sulfur compounds, fats
How to store energy
116
Used in anabolism (create)
What happens to ATP
117
Amino acids to proteins, nucleotides to nucleic acids, sugars to polysaccharides, fatty acids to lipids
ATP Makes what new microbial cells
118
Respiration: oxygen used as electron acceptor (aerobic/anaerobic). Fermentation: organic compounds used as electron acceptor (only anaerobic)
Catabolism (break)
119
Ribosomes
Made of RNA and proteins
120
Peptides
Amino acids formed into chains
121
Form proteins
Peptides form polymers, which form
122
Proteins that catalyze chemical reactions
Enzymes
123
Catabolism
Bacteria can make stinky products by
124
Pathogen
Microorganism that can cause infection
125
Infection
Overgrowth of microoganism in the body
126
Pathogen
What is P. endodontalis considered
127
Virulence factors
Cause disorder
128
Cellular structure (capsular polysaccharide and fimbrae)
Virulence factors comprise both
129
Inflammation, attachment structures
What does capsular polysaccharide and fimbrae do
130
Protease
Gingipain is a type of secreted enzyme
131
Pathogen survival/colonization
Purpose of virulence factors
132
Capsules and slime layers
External cell structures
133
Provide protection and attachment
What do external polysaccharide layers do
134
Tightly, loosely
Capsule is ____ attached, slime layer is ____ attached
135
Establishing pathogenicity
Koch's Postulates
136
1. Isolate pathogen, 2. Grow pathogen in laboratory to obtain a pure culture, 3/ Inoculate healthy individual with sample from pure culture (should cause same disease symptoms), 4. Reisolate same pathogen from individual
What is Koch's Postulates
137
MOST IMPORTANT
1. Bacteria capture enrgy through catabolic reactions w/ organic and inorganic molecules then use energy for anabolism, 2. Catabolism is mediated by proteins -> encoded by genes -> make up genome, 3. Pathogens are disorder-causing microorganisms that cause degradation though catabolic ractiosn and structural features
138
Communicate and cooperate
Bacteria can
139
Build structures, coordinate behavior
They do this by
140
Mold (fungus, eukaryote)
"Black mold" is
141
Bacteria growing in a biofilm
"Red mold" is
142
MOST IMPORTANT
1. Many bacteria grow in structures, stuck to surfaces (biofilms) -- which provide protection, 2. Bacteria must sometimes cooperate and communicate throguh quorum sensing, 3. Biofilms can be very costly to manage and dangerous for human heath
143
Serratia marcescens
Name of red mold
144
Red-shaped bacterium
Shape of red mold
145
Distinctive red pigment (prodigiosin = secondary compound)
Red mold creates what appearance
146
Pathogenic under right conditions
Opportunistic pathogen
147
Commonly studies pathogen of insects, cause disease in corals
S. marcescens as a pathogen
148
Urinary tract, respiratory tract, and eyes
S. marcescens can be a pathogen to humans
149
Can form biofilms on surfaces, attach to abiotic surfaces (shower), and biotic surfaces (eye, urinary tract)
How is S. marcescens a pathogen
150
Structure of polysaccharides, contains bacteria, stuck to surface
Biofilm is a
151
Mushroom structure
S. Marcescens in shower is shaped like
152
Cell-chain or filament biofilms
S. Marcescens in eyeball is shaped like
153
Eats soap scum and shampoo residue
S. Marcescens in shower eats
154
Vary depending on environment/species
Biofilm structures
155
Default
Biofilms are the what type of state for many bacteria
156
Low nutrient, wet environments
Beneficial in what type of environments
157
Stay in place (form where water moves/circulates nutrients)
Why form a biofilm
158
Stays safe (strength in numbers, protection from immune system, antibiotics, stress, predators)
Why else form a biofilm
159
Make friends (involve multiple species, benefit from each other's abilities)
Why else else form a biofilm
160
Stick to it (cell surface proteins (ex. pili, fimbriae, flagella)
How to stick to surfaces to form biofilm
161
Extracellular polymer substances (EPS)
How to build matrix to form biofilm
162
Cells cooperate to form matrix, strength in numbrs
How to form matrix
163
Cell-cell communication (quorum sensing
How do bacteria know if there are enough cells to make biofilm
164
Minimum number of individuals needed for a group to conduct business
Quorum
165
Minimum density of individuals, not absolute number
For bacteria
166
Access their own density
Quorum sensing lets bacteria
167
Cell produces signal that diffuses into environment, signal enters other cells, if enough signal -- "turns on" a trait
How does quorum sensing work?
168
Cost billions of dollars yearly (cleaning/maintaining/replacing equipment, water/food contamination, infections)
Why care abt biofilms?
169
Associated w disease, make antibiotics less effective, increase chance of nosocomical infection (difficult to clean, forms on urinary catheters)
Biofilms cause serious medical problems
170
Disrupting quorum sensing could be used to treat infections, possible target for antibiotics
Quorum sensing if involved in biofilm formation/pathogen production of virulence factors
171
MOST IMPORTANT
1. Biofilms complex structures that are important to bacteria (requires bacterial cooperation and lead to benefits), 2. Bacteria can communicate w each other through quorum sensing (cells make signals that other cells receive and respond to), 3. Biofilms can be very costly to clean up and lead to contamination and infection
172
Intraspecies communication
When is it good to have strength in numbers
173
Biofilm formation, make virulence factors that let pathogens invade host tissue, make products that allow them to work together for motility
Examples of quorum sensing for intraspecies
174
Predatory bacteria, hunt in cooperative "wolf packs", and work together to build spore producing "fruiting bodies"
Swarming motility in Myxococcus
175
Interspecies communication
When you want to eavesdrop or cooperate
176
Pick up signals from other species, cooperate (biofilm formation)
Examples of quorum sensing for interspecies
177
Universal autoinducers
Frequently turn on traits in many other bacteria
178
Diarrhea, nausea, abdominal pain
Gastroenteritis symptoms
179
Cholera, Typhoid
Infectious agents (bacteria)
180
Cryptosporidium, Giardia
Infectious agents (protozoa)
181
Polio, Hepatitis A
Infectious agents (virus)
182
Wastewater treatment and water purification
Prevention of waterborne diseases
183
Sedimentation, coagulation, filtration, chlorination, storage, distribution
Water treatment process
184
Indicator organisms
Potable/recreational water regularly tested for
185
Coliform, fecal coliform, escherichia coli
Types of indicator organisms
186
Gram negative, non-sporulating facultatively aerobic rods that rerment lactose to makes gas within 48hr at 35C
Coliform
187
Coliforms from the gut of warm blooded animals
Fecal coliforms
188
Common fecal coliform
Escherichia coli
189
Gram negative, short generation time (20 min in 37C)
About Escherichia coli
190
All DNA found in an organism (or virus)
Genome
191
Has essential genes
Chromosomes
192
oriC (origin of chromosome replication)
Single, closed circular chromosome w a single site where DNA replication begins
193
E. coli K12
Workhorse of the lab
194
E. coli A and B1
Apart of our gut microbiome (good bacteria)
195
E. coli 0157:H7
Produces Shiga toxin (food borne disease)
196
Microbiota, proteome, metabolome, microbiome
Types of microbiomes
197
Nutrition, immunomodulation, mood/mental health, colonization resistance
What goods and services to microbiomes do
198
Disruption of homeostasis between gut microbiota and host
Dysbiosis
199
Human development, nutrition, gut dysbiosis (IBD), Obesity, pharrmacology, antibiotics, human behavior, neurological disease, cancer
What conditions may be impacted by the microbiome
200
Collection of all microorganisms associated w a place
Microbiome
201
20,000 genes
Human genome has how many genes
202
3 million genes
Human microbiome has how many genes
203
Conditions
What dictates the kind of microbes that predominate
204
Skin is desiccating, salty, acidic, inhospitable
Skin microenvironments characteristics
205
Higher moisture
Colonization occurs mostly in areas with
206
Gram positive and desiccation resistant
Most skin-colonizing bacteria are:
207
Firmicutes (Staph, strep (boils)) and Actinobacteria (Propionbacterium acnes)
Skin pathogens
208
Dental plaque
As food/saliva passes our teeth, there is selective pressure for organisms to form a biofilm on tooth surfaces
209
Streptococcus spp and others produce polysaccharide capsulre
What forms as part of matrix of dental plaque
210
Hedgehog structure
Structure of dental plaque
211
Produce acid from sugars
Lactic acid bacteria and others
212
5.3
Critical pH for enamel dissolution is
213
Low pH, sparse colonization
Upper GI tract
214
specialized fermentation vessel
Large intestine
215
Nearly sterile
Low pH, stomach was considered
216
Helicobacter pylori
Motile spiral bacteria isolated from epithelium of gastric ulcers
217
Campylobacter
Helicobacter pylori somewhat related to ..., which caused gastroenteritis
218
Responsible for most gastric ulcers
Helicobacter pylori responsible for
219
Resistance, especially from pharma
Helicobacter pylori met with considerable
220
Infected w Helicobacter
Nearly all mammals w acid stomachs
221
Modulate (educate) the immune resposne
H pylori helps...
222
Due to antibiotic use
> 10% western children are infected w H. pylori
223
peptic ulcer disease, gastroesophageal reflux disease
Consequences of no H. pylori
224
Overly sanitized world, exposd to many fewer microbes, wiping out important parts of our mictobiota when we take antibiotics, used to have helicobacter/parasites/worms and tuned to them, absence of these led to immune disfunction, people have tried to infect themselves w hookworms to overcome immune problems
Hygeine hypothesis
225
Holding/dewatering tank
Large intestine was considered a ... for undigested food
226
Complex/dynamic anaerobic microbial ecosystem
Large intestine now considered
227
Fermented to volatile fatty acids -> absorbed by bloodstream -> used as carbon/energy source by host
What happens to food in the large intestine
228
Hunter-gatherer's nutrition
Fermentation supplied a significan fraction of...
229
Discourage colonization/overgrowth of pathogens, provide 10-15% calories from food (especially access to complex fatty acids), produce vitamins, help educate immune system and trigger maturation of gut, microbial metabolic byproduct modulate inflammatory response, impacts on conditions
Benefits of healthy gut microbiome
230
First contacts with mom, then environment
Where do we get out gut microbes?
231
Assembly influenced by diet (formula vs. breastmilk), altered by antibiotics, early conditions influence adult microbiota, genetics not so important
Community changes
232
Fetus is sterile -> first exposure during birth, mother's milk/other environmental sources seed the GI tract and all external sites of body, community shaped by diet, environment, and genetic factors
Colonization factors
233
Inoculum
Colonized with... by our mothers
234
Bifidobacterium
Actinobacterium with a metabolism similar to LAB
235
Desirable probiotic organism
Bifidobacterium is considered a
236
Termination
What of breast feeding leads to more adult-like microbiota
237
Clostridium botulinum
Honey contains what spors that can colonize an immature GI tract
238
Probiotics
Live microbes consumed to provide a health benefit by altering gut function
239
Prebiotics
Foods/supplements that alter gut community function
240
Drug development, customized medicine
Microbial enzymes interact w drugs, alter their efficiacy and can alter severity of side effects, could be tailed to microbiome
241
Fungal infections
Athlete's foot and jock itch are what type of infections
242
Eukaryotic microorganisms
Fungi is what type of microorganism
243
MOST IMPORTANT
1. Fungi have positive/detrimental impacts on human life, 2. Fungi have unique life cycles involving asexual/sexual reproduction, 3. Inhibiting fungal infections involves inhibiting cell wall synthesis and opening transmembrane channels in cell walls
244
Tinea cruris
Jock itch scientific name
245
Tinea pedis
Athlete's food scientific name
246
Eukaryotes, achlorophyllous, have filamentous somatic structures, produce spores, live by absorptive nutrition, sexual/asexual reproduction
Fungal characteristics
247
Economically significant, human disease, ecosystem services
Why is fungi important to us
248
Mycoses
Mucormycosis occurs in immunocompromised patients
249
Mycotoxins
Plant pathogenis fungus that makes neurotoxins
250
Life cycle stage
Structures reflect
251
Somatic (growing) structures filamentous
How do the structures grow?
252
Thick capsules
What do they have outside of cell walls
253
Extra cellular digestion
Obtain nutrients and energy by
254
Absorptive nutrition
Mechanism to obtain energy/nutrients
255
Digestive enzymes excreted into a substrate, degrade substrate
What happens during absorptive nutrition
256
Absorbed through cell walls
During absorptive nutrition, the smaller molecules are
257
Aspergillus sp.
Asexual spores (Conidia)
258
Ringworm
Causes Jock Itch and Athlete's foot
259
Candidia albicans
Oral and vaginal infections
260
Invasive
Candidia albicans can form a ... infection
261
Secreted enzymes used to absorb nutrients
Virulence factors of Candidia albicans
262
Because these are eukaryotes, antibiotics used for bacteria is ineffective
Treatment of fungal infections
263
Cell wall components unique to fungi (Echinocandins, Azoles, Amphotericin B)
Treatments target what
264
Debridement (removal by surgery)
Severe invasive fungal infections require
265
Aspergillosis
Inhalation of common mold
266
Cryptococcus neoformans
Inhalation of Cryptococcus neoformans spores
267
Mucormycosis
Inhlation of common bread mold spores
268
MOST IMPORTANT
1. Fungi have significant economic, ecological/human health importance, 2. Fungi have unique cell walls mechanisms for nutrituon/generating enrgy and undergo a/sexual life cycle stages, 3. Fungi ar sometimes commensal but can cause infections which are trated by targeting cell wall components
269
Aquatic microorganisms
Swimming pools re engineered habitats for
270
Pathogens and non-pathogens
Bacteria inhabiting them include
271
MOST IMPORTANT
1. Human pathogens can exist in swimming pools but most killed by sanitation, 2. Microbial communities are structured by their habitat, 3. Microorganisms can be introduced from external sources and be maintained in refugia
272
Count by plating
How to count bacteria
273
Not everything grows on solid media, diff bacteria require diff growth media, some bacteria like to remain rare
Problems with plating bacteria
274
Bacteria too small for light microscopy/easily confused
Problems with microscopy
275
Fluorescent stains
Combined with what type of stains to allow you to count cells
276
Autofluorescence (unstained)
Natural pigments (ex. Phycobilins in cyanobacteria)
277
DAPI & Acridine Orange
DNA Stain
278
SYBR Green I / SYBR Gold
Used in bacterial and viral counts
279
More organic matter = more bacteria
Bacteria grow where there is food
280
Survive sanitation of municipal water, evolve to tolerate sanitation procedures (chlorine), come from bathers
Why is there still bacteria in pool water
281
Gram positive, firmicute, facultative aerobe, no spores, part of skin microbiom, cause infection when skin layers breached
Staphylococcus aureus
282
Coagulase, several exotoxins, evades host immune system
Causes pathology through virulence factors
283
Lots of potential for fecal bacteria to enter swimming pools
Enterococcus faecalis
284
Resistant
Biofilms are somewhat ... to chemicals
285
Form a matrix which can be impenetrable
Why are they somewhat resistant
286
M. tuberculosis, actinobacteria, gram positive (no stain tho bc too waxy), difficult to treat, asymptomatic infection in large %
Mycobacteria
287
Non-tuberculosis mycobacteria (NMTs)
What can also cause human disease
288
Leprosy
Many species of NMTs can cause
289
Forms strong biofilms that are difficult to penetrate w antibiotics
Mycobacteria forms...
290
Bacterium that infects skin and nerves
M. leprae (leprosy/hansens' disease)
291
Cooler temperatures
Conditions for M. leprae
292
Caused inflammatory response -> turns tissue necrosis/death
Infection of M. leprae
293
Detected in swimming pool/spa waters, highest in whirlpool
Mycobacteria found a lot in
294
Skimmers remove floating materials, main drain removes sinking material, water filtered to remove cells/debris
Swimming pool filtration
295
Membrane filters remove debris/cells by passing water through cartridge
Pool filters
296
Produces enzyms to kill pathogens (helps purify water)
Sand filtration
297
Bacterial biofilm on surface of sand
Schmutzdecke
298
High salinity kills pathogens, can make pathogens less stable
Why saltwater pools don't have much bacteria
299
Reductive dechlorination
Can use chlorine as an electron acceptor (some bacteria can eat)
300
MOST IMPORTANT
1. Types of bacteria that thrive form spores or form biofilms (both resistant to chlorine), 2. Some bacteria may use chlorine in respiration as electron acceptor, 3. Bacteria in biofilms (pipes/surfaces) ma seed bacteria into overlying waters representing refugia, 4. Some bacteria may be pathogens
301
Preserve
Ice on skating rinks does what to bacteria
302
Accidental ingestion of ice/contact between ice and skin can cause infection by common commensal bacteria
Why would this be a problem?
303
Live/grow at temperature >-24C
Psychophilic bacteria
304
Live/grow at temperature >-20C
Extremophiles
305
Bind ice crystal
Proteins do what to prevent freezing of cell contents
