Exam 1 Chap. 1-5 Flashcards
(363 cards)
1
Q
Chlorine destroys ___ and can react with compounds in water, disrupting germicidal activity and produces possible ___.
A
All microorganisms and viruses; carcinogens.
2
Q
What are examples of biofilm?
A
Slipperiness of rocks, slimy gunk of sink drains, scum in toilet bowls, and plaque.
3
Q
How does immersion oil (100x magnification) work?
A
The oil has the same refraction index as glass so it prevent light from refracting.
4
Q
What is a prion?
A
An infectious or misfolded version of a protein found in the brain.
5
Q
What happens in the phase of prolonged decline?
A
Some cells may survive if adapted to tolerate worsened conditions.
6
Q
Extremophiles (___) live in ___.
A
Mainly archaea; harsh environments.
7
Q
The elimination of most pathogens can be escribed as ___.
A
Disinfection.
8
Q
What is exocytosis?
A
Internal vesicles fuse with the cytoplasmic membrane and release contents.
9
Q
List the characteristics of Archaea.
1. Cell type: ___.
2. # of cells: ___.
3. Membrane-bound organelles?: ___.
4. Unique ribosomal RNA sequences?: ___.
5. Peptidoglycan?: ___.
6. Size: ___
A
- Prokaryotic.
- Unicellular.
- No.
- Yes.
- No.
- 0.3-2nm.
10
Q
Incineration is a method of ___ that burns cells to ashes.
A
Dry heat sterilization.
11
Q
Prokaryotic ribosomes are ___ (30S + 50S subunits) and eukaryotic ribosomes are ___ (60S + 40S subunits).
A
70S; 80S.
12
Q
What are key characteristics of eukaryotes?
A
Membrane-bound nucleus and organelles.
13
Q
How do the lipid tails of Archaea differ from that of Bacteria?
A
They are not fatty acids.
14
Q
What are fatty acids?
A
Linear chains of C and H atoms with a carboxyl group.
15
Q
What happens in the exponential (log) phase?
A
Cells divide at a constant rate and generation time is measured (sensitive to antibiotics).
16
Q
Most infections seem to involve biofilms because ___.
A
The microbes are resistant to the immune system and antibiotics.
17
Q
What does S reflect?
A
How fast ribosomes settle when centrifuged.
18
Q
The time required to kill 90% of a population can be described as ___.
A
Decimal reduction time (D value).
19
Q
What is the difference between passive transport and active transport?
A
Passive transport does NOT require energy while active transport does either through proton motive force or ATP.
20
Q
How do John Needham’s, Father Spallanzani’s, and Louis Pasteur’s proposals align?
A
They all studied broths and the effect of boiling and exposure to air.
21
Q
What is a compound?
A
A compound is a molecule containing atoms of different elements.
22
Q
What are 4 functions of microorganisms?
A
- Recycle nutrient.
- Produce oxygen through photosynthesis.
- Undergo nitrogen fixation.
- Decompose material.
23
Q
Runs are ___ and tumbles are ___.
A
Straight lines; direction changes.
24
Q
(HPP) ___ decreases the number of microorganisms in commercial food products.
A
High pressure processing (HPP).
25
Antiseptics are chemicals used on ___.
Living tissues.
26
What happens in the death phase?
The total number of viable cells decrease at a constant rate but much slower than cell growth.
27
The production of living things from other living things can be described as ___.
Biogenesis.
28
What is a pathogen?
A disease-causing microorganism.
29
What is a virus?
An acellular infectious agent that consists of DNA or RNA and infects hosts.
30
Weak organic acids (benzoic, sorbic, propionic) affect cell membrane function and controls ___.
Molds and bacteria in foods.
31
What are 3 limitation using alcohols as germicides?
1. Quick evaporation times.
2. Limiting contact time.
3. Can damage rubbers/plastics.
32
The top of shake tubes is ___ (O2 present) and the bottom is ___ (O2 absent).
Aerobic; anaerobic.
33
___ are used to join bacteria for DNA transfer.
Sex pili.
34
What are the subunits and functions of lipids?
Fatty acids; components of cell membranes.
35
Peritrichous flagella ___ the cell while polar flagella are ___ of the cell.
Surround; on one end.
36
All microorganisms require ___ and ___.
Water; dissolved salts/sugars.
37
Mesophiles (25 C - ___) includes ___ (35 C - 40 C).
45 C; pathogens.
38
Filtration is used to remove organisms from ___ using ___.
Heat-sensitive fluid; membrane filters/microfilters (uses vacuum,) and depth filters (uses electrical charge).
39
What is a pure culture?
A population of cells derived from a single cell.
40
The spirochete shape of a cell is ___.
Squiggly.
41
A plate dilution series is used to obtain ___ colonies.
30 - 300.
42
Iodine kills ___ and use as a tincture and idophore.
Vegetative spore but unreliable on endospores.
43
What are examples of the ultra-high-temperature (UHT) method?
Shelf-stable juice boxes and milk at 140 C for a few seconds then rapidly cooled.
44
Dry heat is less effective that moist heat due to ___ times and ___ temperature required.
Longer; higher.
45
__ provide *STRENGTH* to the fluid structure of membranes.
Sterols.
46
What does the cortex do in sporulation?
Maintain the core in a dehydrated state and protects it from heat.
47
What are the 3 points of the pH scale?
Acidic (< pH 7), neutral (pH 7), and basic (> pH 7).
48
What are flagella composed of?
The basal body (anchors to cell wall/membrane), hook, and filament.
49
Cells capable of multiplying can be described as ___.
Viable cell count.
50
What are Joseph Lister's studies and contributions?
He introduced methods to prevent infections of wounds and had oral Listerine named after him since it was introduced as a surgical antiseptic.
51
Pasteurization destroys ___.
heat-sensitive pathogens and spoilage organisms.
52
The temperature of refrigeration is ___.
4 C.
53
List 3 important facts about microorganisms.
1. Existed for 35 million years.
2. Modern microorganisms evolved from a common ancestor.
3. Our life depends on them.
54
___ is the diffusion of water across a selectively permeable membrane due to unequal solute concentrations.
Osmosis.
55
What is the tertiary structure of polypeptides?
3D shaped of folding due to R group interactions.
56
What are the 4 groups of Eukarya?
1. Fungi.
2. Algae (protist).
3. Protozoa (protist).
4. Helminths (worms).
57
What are Antony van Leeuwenhoek's studies and contributions?
(HINT: lake water and basic microorganisms.)
He studied lake water and "animalcules;" invented the simple magnifying glass.
58
What are the energy sources and size range of fungi?
1. Use organic material for energy.
2. Microscopic (yeast) and macroscopic (molds/mushrooms).
59
What is the function of mitochondria?
Generate ATP and the inner membrane forms folds (cristae), increasing the surface area for ATP generation.
60
What are some examples of EIDs?
1. Ebola virus.
2. Zika.
3. Middle East Respiratory Syndrome (MERS).
4. Flu.
5. Lyme disease.
6. AIDS.
7. Hantavirus.
8. Mad cow disease.
61
The belief that life arose spontaneously from non-living material is called ___.
Spontaneous generation.
62
Obligate intracellular agents ___ using host cell machinery/nutrients and are ___ outside of the host.
Multiply; inactive.
63
Ribosomal size and density are expressed as ___.
S (Svedberg unit).
64
How does light microscopy work?
Light passes through a specimen then through a series of lenses to magnify the image.
65
___ all the cell to detect/respond to signals; viruses use them to enter/exit cells.
Lipid rafts.
66
What do cell envelopes consist of?
Cytoplasmic membrane, cell wall, and capsule.
67
The electrochemical gradient is maintained by ___.
Sodium or proton pumps.
68
Growth can be calculate as Nt = N0 * 2^n, in which Nt = ___, N0 = ___, and n = ___.
of cells at time t; initial # of cells; # of generation at that point.
69
Endosomes fuse with ___ and the material is degraded into ___.
Lysosomes; endolysosomes.
70
How is atomic mass different from the mass number.
The mass number is the total number of protons and neutrons in one isotope while the atomic mass is the average mass number of all isotopes of an element.
71
What are the subunits nucleic acids?
Nucleotides.
72
What are saturated fatty acids?
Fats; no double bonds.
73
What are the two functions of peroxisomes?
1. Use O2 to degrade lipids/detoxify chemicals.
2. Protects the cell from the toxic effects of hydrogen peroxide and superoxide by degrading them.
74
Psychrophiles (___ - 15 C) are found in the ___ regions.
-5 C; Arctic/Antarctic.
75
Water flows from ___tonic to ___tonic solutions.
Hypo; hyper.
76
What components do eukaryotic cells consist of?
Membrane-bound organelles and a nucleus.
77
What are some characteristics of protozoa?
Have no rigid cell wall and most are motile.
78
Microbes that grow optimally at pH <5.5 are called ___.
Acidophiles.
79
What is the function of aldehydes? (light switch)
Inactivates proteins and nucleic acids.
80
What are 3 benefits of phenolic compounds?
1. A wide activity range.
2. Reasonable cost.
3. Remains effective in the presence of detergents and organic contaminants.
81
What are the 6 steps of the scientific method?
(HINT: 1. O/Q, 2. H, 3. E, 4. D, 5. C, 6. M/R/C)
1. Make an observation and ask a question.
2. Make a hypothesis.
3. Conduct experiments to prove/disprove your hypothesis.
4. Collect data.
5. Draw a conclusion.
6. Report your methods, results, and conclusions.
82
Retorts are industrial-sized ___ that are used in the ___.
Autoclaves; commercial canning process.
83
Exponential growth is when ___.
The population doubles each division.
84
What are Martinus Beijerinck's studies and contributions?
(HINT: elements + microorganisms.)
He isolated nitrogen-fixing rhizobia from root nodules of legumes which led to studies of the relationship between elements and microorganisms.
85
What are energy sources and size range of helminths?
1. Use organic material for energy.
2. Microscopic eggs/larval forms and macroscopic adult worms.
86
___ cell takes up material from surrounding environment by forming invaginations in cytoplasmic membrane.
Endocytosis.
87
The use of microbiological/biochemical techniques to solve issues can be described as ___.
Biotechnology.
88
Capnophiles require ___.
Increased O2.
89
Organic molecules that an organism cannot synthesize, must be present in the environment, and reflects biosynthetic capabilities can be described as ___.
Growth factors.
90
What is the function of phosphorus?
Component of nucleic acids, membrane lipids, and ATP.
91
What is a buffer?
A buffer is a chemical used to keep the pH of substances balanced (neutral) by releasing/combining with H+.
92
Pinocytosis is common in ___ and forms ___.
Animal cells; endosomes.
93
Why are viruses, viroids, and prions considered non-living?
They are not composed of cells.
94
Cells in canned foods grow in ___ anaerobe conditions and produce ___.
Low-acid; Clostridium botulinum endospores.
95
Reactive oxygen species (ROS) include chemicals such as ___.
Superoxide (O2-) and hydrogen peroxide (H2O2).
96
What are the steps of endospore staining?
1. The endospore resists the Gram stain and appears as a clear object.
2. Endospore stains use heat to facilitate the uptake of malachite green.
3. Counterstain (safarin) colors other cells pink
97
Prions are thought to be destroyed at ___ for 1 hour.
132 C.
98
What are the steps of differential staining?
1. Flood smear with a primary stain.
2. Rinse and flood with iodine, a mordant that stabilizes the dye in the cell.
3. Rinse and briefly add alcohol, decolorizing agent, to remove the dye complex from Gram-negative cells.
4. Rince and flood smear with counterstain that adds a different color to Gram-negative cells.
99
What does the exponential (log) phase produce?
Primary metabolites (amino acids) and secondary metabolites (antibiotics).
100
What is the function of sulfur?
Component of some amino acids.
101
What are Louis Pasteur's studies and contributions?
(HINT: bendy flasks.)
He studied the exposure of and microorganisms contamination of broth. He invented swan-neck flasks in which the bend of the neck would trap the microorganisms keeping the broth sterile, but if tilted, would contaminate the broth.
102
Halotolerants withstand ___ salt concentration.
<10%.
103
What does moist heat do to destroy microorganisms?
Denatures proteins.
104
What happens when peptidoglycan is interfered with?
The cell wall is weakened and the cell can burst.
105
What is peptidoglycan unique to?
Bacteria.
106
Mitochondrial DNA sequences resemble ___ and chloroplast DNA sequences resemble ___.
Obligate intracellular parasite (rickettsias); cyanobacteria.
107
Nitrate and nitrite are used in ___ and ___ concentrations make meats pink.
Processed meats; higher.
108
Gamma rays are generally used after ___.
Packaging.
109
What are enzymes?
Enzymes are catalysts that help speed up biological functions and help break covalent bonds.
110
What are some commercial benefits of synthesized microorganisms?
1. Antibiotics (disease treatment).
2. Ethanol (biofuel).
3. Hydrogen gas/certain oils (possible biofuel).
4. Amino acids (dietary supplements).
5. Insect toxins (insecticides).
6. Cellulose (headphones).
7. Hydroxybutyric acid (diapers/plastics).
111
There's depleted ___ and accumulated wastes at the ___ of a colony.
O2/nutrient; center.
112
Measure biomass by ___ instead of number of cells.
Measuring cell mass.
113
How is antibiotic resistances spread?
Plasmid sharing.
114
Organisms too small to be seen with the naked eye can be described as ___?
Microorganisms.
115
What is the difference between non-polar and polar covalent bonds?
Non-polar covalent bonds have an equal sharing of electrons while the electrons of polar covalent bonds are shared unequally.
116
What does DPB stand for?
Disinfection by-products.
117
A protein is made of one or more long ___(s) folded.
Polypeptides.
118
Edge cell may experience ___ while center cells are in the ___ phase.
Exponential growth; death.
119
How many cells form a colony?
~1 million cells.
120
What are Francesco Redi's studies and contributions?
(HINT: bugs and reproduction.)
He studied worms on rotting meat in two separate jars and suggested that they came from the eggs of flies.
121
What components to prokaryotic cells consist of?
Cell envelope, cytoplasm, nucleoid, and sometimes appendages.
122
Sterile items are free of microbes including endospores but not ___.
Prions.
123
What do Gram-positive cell walls prevent.
The crystal violet-iodine complex from being washed out.
124
What gives the slimy appearance of biofilms?
Extra polymeric substances (EPS).
125
Heat treatment is used to ___.
Destroy/remove/inhibit microbes from perishables, but alter taste and appearance.
126
Mycobacterium cells walls are waxy making them resistant to ___.
Chemical treatments.
127
What is a viroid?
An obligate intracellular agent that consists of a single RNA piece and causes plant diseases.
128
What are carbon skeletons?
Arrangements of carbons.
129
What do Gram-positive cell walls contain?
A thick peptidoglycan layer with teichoic acids above and gel-like material below.
130
What are endospores?
Heat-resistant microbes.
131
What is between the cytoplasmic membrane and outer membrane of Gram-negative cells?
Periplasmic space.
132
The production of medications by certain microorganisms can be described as ___.
Genetic engineering.
133
What is a polymer?
A combination of monomers.
134
What are Ferdinand Cohn's studies and contributions?
(HINT: minecraft blossoms.)
He discovered endospores. He showed the conflicting reports of Pasteur's experiments with other experiments were caused by these heat-resistant microbes.
135
What are 4 effects of normal microbiota on your body?
1. Prevents disease.
2. Aid in digestion.
3. Promote the development of the immune system.
4. Affect brain chemistry and body weight.
136
Ethylene oxide is a gaseous sterilant used for ___ and reacts with proteins to destroy ___.
Heat/moisture sensitive items; microbes, including endospores and viruses.
137
Protozoan cysts/oocysts are resistant to ___ and are destroyed by ___.
Disinfectants; boiling.
138
What do endosymbionts do?
Carry DNA for some ribosomal proteins/ribosomal RNA.
139
Biosafety levels range from BSL-1 (___) to BSL-4 (___).
Microbes not known to cause disease; lethal pathogens in which no vaccine/treatment exists.
140
Semi-critical instruments include ___ and come into contact with ___.
Endoscopes/endotracheal tubes; mucous membranes.
141
What is the minimum resolving power of a light microscope?
0.2 micrometers.
142
What are 3 limitations of ethylene oxide?
1. Explosive.
2. Toxic.
3. Potentially carcinogenic.
143
The removal or destruction of all microorganisms/viruses can be described as ___.
Sterilization.
144
Metachromatic granules stain red with ___.
Methylene blue.
145
What does the Golgi apparatus do for molecules?
Molecules are sorted and delivered in vesicles.
146
What are some characteristics of Bacteria?
1. Single-celled prokaryotes.
2. A rigid cell wall containing peptidoglycan (only in Bacteria).
3. Use flagella to move.
4. Multiply by binary fission.
147
What is a molecule?
A molecule is two or more atoms joined together through covalent bonds.
148
How do ionic bonds form and what do they produce?
Ionic bonds are formed through the attraction between positive and negative charged and the form electrolytes (conduct electricity).
149
What is a biofilm?
A polymer-encased community.
150
What do capsule stains allow the observation of?
The gel-like layer that surrounds microbes.
151
___ is an unstable form of oxygen and used as an alternative for ___ as a disinfectant for drinking and wastewater.
Ozone (O3); chlorine.
152
What is an ion?
An atom that has gained or an electron(s).
153
What are energy sources and size range of protozoa?
1. Use organic material for energy.
2. Microscopic (single-celled).
154
Wavelength is ___ proportional to frequency and high frequency has ___ energy than low frequency.
Inversely; more.
155
156
The harmful by-products of using O2 in aerobic respiration can be described as ___.
Reactive oxygen species (ROS)
157
What is an element?
A simple atom that cannot not be broken down smaller.
158
Psychrotrophs (15 C - ___) are important in the ___.
30 C; spoilage of refrigerated foods.
159
Hypotonic solutions are ___ while hypertonic solutions are ___.
Dilute; concentrated.
160
Most microbes are ___ with a pH of 5-8.
Neutrophiles.
161
Heat and irradiation damages ___ and moist heat/liquid chemical disinfectant cannot treat ___.
Plastics; moisture-sensitive material.
162
Quaternary ammonium compounds (quats) are ___ detergents with ___ toxicity so it's safe to use as a food preparation surface disinfectant.
Cationic; low.
163
Who observed "microscopical mushrooms"?
Robert Hooke.
164
Microbes that grow optimally at pH >8.5 are called ___.
Alkaliphiles.
165
What is an isotope?
Isotopes are two of the same element that have different mass numbers due to a difference in the number of neutrons.
166
167
What does NAG stand for?
N-acetylglucosamine.
168
What is an aquaporin?
A water passage and the channels are gated pores that allow small molecules/ions to diffuse.
169
Blood agar is different and Beta-hemolysis produces a ___ zone and Alpha-hemolysis produces a ___.
Clear; greenish partial clearing.
170
Explain the hydrogen bonds of solid H2O.
Each hydrogen in a water molecule can form 4 bonds and create the less dense ice.
171
Who observed "animalcules" and invented the simple magnifying glass?
Antony van Leeuwenhoek.
172
The reduction of microbial populations to meet health standards that minimize spread of disease can be described as ___.
Sanitization.
173
How do filamentous molds spread?
Microscopic spores called concilia.
174
What are characteristics of a prion?
1. Misfolded proteins that come in contact with normal proteins can misfold them too.
2. Abnormal proteins form fibrils.
3. Cells die leaving spaces in the brain (spongiform encephalopathy).
4. Resistant to usual sterilization procedures.
175
What is an organic compound?
Compounds that have carbon and hydrogen bonded together.
176
What is contrast?
How easily cells can be seen.
177
You can detect cell products using:
1. pH indicators.
2. Durham tubes to trap gas.
3. CO2 production.
178
Complex media contain a ___ and the exact composition is ___.
Variety of ingredients; highly variable.
179
What is the function of ribosomes?
Ribosomes facilitate the joining of amino acids for protein synthesis.
180
Non-enveloped viruses lack a ___ and are resistant to ___.
Lipid envelope; disinfectants.
181
What are the trace elements of cells?
Cobalt, Zinc, Copper, Molybdenum, and Manganese.
182
(GRIMES) ___ can interfere with heat penetration/action of chemicals.
Dirt, grease, and body fluids.
183
What does the ETC do for the cell?
Creates a gradient across the membrane to drive ATP synthesis and some forms of motility.
184
What are endospores resistant to?
Heat, desiccation, chemicals, UV light, and boiling water.
185
___ are chemicals that bacteria sense and move toward (nutrient) or away from (toxin).
Chemotaxis.
186
The hastened decay of pollutants using microorganisms can be referred to as ___.
Bioremediation.
187
Disinfectants are chemicals used on ___.
Inanimate objects.
188
___ is the movement from high concentration to low concentration for equilibrium.
Simple diffusion.
189
List the characteristics of Bacteria.
1. Cell type: ___.
2. # of cells: ___.
3. Membrane-bound organelles?: ___.
4. Unique ribosomal RNA sequences?: ___.
5. Peptidoglycan?: ___.
6. Size: ___
1. Prokaryotic.
2. Unicellular.
3. No.
4. Yes.
5. Yes.
6. 0.3-2nm.
190
What is a covalent bond?
(HINT: COvalent.)
A bond formed through the sharing of electrons.
191
The capturing/concentrating of microbes by filtration can be described as ___.
Membrane filtration.
192
1. Photo - ___.
2. Chemo - ___.
3. Litho - ___.
4. Organo - ___.
5. Auto - ___.
6. Hetero - ___.
1. Light.
2. Material.
3. Inorganic.
4. Organic.
5. CO2.
6. Organic compounds.
193
What are examples of the high-temperature-short-time (UTST) method?
Milk at 72 C for 15 seconds and ice cream at 82 C for 20 seconds.
194
What is pH?
pH is the measure of acidity (H+ concentration).
195
A pure culture can be maintained as stock culture being frozen at ___ and mixed with ___ to prevent ice crystal formation.
-70 C; glycerol.
196
Chemically define media is composed of ___ of pure chemicals and grow ___ as cells must synthesize components.
Exact amounts; slower.
197
What does a lipopolysaccharide (LPS) do? (soldiers)
Signals the immune system of invasion by Gram-negative bacteria.
198
What are the major elements of cells?
Carbon, Oxygen, Hydrogen, Nitrogen, Sulfur, Phosphorus, Potassium, Magnesium, Calcium, and Iron.
199
Chemotrophs obtain energy from ___.
Chemicals/organic material.
200
A grape-like group of cells is described as a ___.
Cluster.
201
Why are steroids considered lipids?
Due to their water insolubility.
202
Agar is used to solidify mediums that liquify ___ and solidifies ___.
>95 C; <45 C.
203
Autoclaves are used to sterilize using ___ in which ___ raises temperature and kills endospores.
Pressurized steam; increased pressure.
204
What are Robert Koch's studies and contributions?
He studied disease-causing bacteria and found that solidifying liquid media with gelatin (agar) to allow a single bacteria to grow.
205
The charged hydrophilic and hydrophobic regions of ___ aid in the removal of ___.
Quats; dirt, organic matter, and organisms.
206
There's little competition for ___ on the ___ of a colony.
O2/nutrients; edge.
207
What 3 common items must be free of microorganisms?
1. Pharmaceuticals.
2. Deodorants.
3. Cosmetics.
208
The ability of some thermophiles being able to survive in canned food but are not concerning due to them needing high temperatures is considered ___.
Commercially sterile.
209
Amino acids are held together by peptide bonds, which are ___.
A covalent bond formed by dehydration synthesis reactions between carboxyl and amino groups.
210
What is a disease that has become more common in the last 35 years?
(HINT: EID)
Emerging Infectious Disease.
211
Myxobacteria collectively ___ enzymes and ___ organic material.
Release; degrade.
212
The increase in the number of cells in a population is described as ___.
Microbial growth.
213
How to acidic dyes work?
Acidic dyes are negatively charges so cells repel the negatively charged dye making them stand out against the background.
214
Sterilants (sporocides) destroy ___ and use ___.
All microbes; heat-sensitive critical instruments.
215
A group of cells is described as a ___.
Packet.
216
What are "microscopical mushrooms"?
Common bread mold.
217
1. Obligate aerobes ___.
2. Facultative aerobes ___.
3. Obligate anaerobes ___.
4. Microaerophiles ___.
5. Tolerant anaerobes (obligate fermenters) ___.
1. Require O2.
2. Use O2 but do not require it.
3. Do NOT use O2.
4. Require small amounts of O2.
5. Can grow in O2 but do not use it.
218
A long chain of cells is described as a ___.
Chain.
219
What happens in the stationary phase?
Nutrient levels are too low to sustain growth and total number remain constant.
220
What are microtubules?
Long, hallow structure made of tubulin found in mitotic spindles, cilia, and flagella.
221
What are cell membranes made of?
Phospholipids with hydrophilic heads facing outward and hydrophobic tails facing inward.
222
Phenolic compounds kill most ___ by destroying ___ and denature proteins but are not reliable on all virus groups.
Vegetative proteins; cytoplasmic membranes.
223
What is resolution?
The resolving power, or the ability to distinguish two very close objects; the amount of distance needed to view two objects as separate.
224
The process in which old organelles/vesicles fuse with lysosomes can be described as ___.
Autophagy.
225
Bacterial endospores are most resistant and can only be destroyed with ___.
Extreme heat/chemical treatment.
226
What are the 5 phases of the growth curve?
1. Lag phase.
2. Exponential (log) phase.
3. Stationary phase.
4. Death phase.
5. Prolonged decline phase.
227
The pleomorphic shape of a cell is ___.
Irregular.
228
What are 3 facts about endospores?
1. Virtually everywhere.
2. Remain dormant for 100+ years.
3. Produced by members of Bacillus and Clostridium.
229
Turbidity is measured with ___ in which the more cells present in the sample, the ___.
Spectrophotometers; less light is measured.
230
Phosphorus and iron are limiting nutrients that ___.
Dictate the maximum level of growth.
231
What are the 4 steps of preparing a shake tube?
1. Boil nutrient agar to drive off O2.
2. Cool to just above solidifying temperature.
3. Add microorganisms.
4. Gently swirl.
232
Germination is triggered by ___.
Heat and chemical exposure; not a means of reproduction.
233
Environmental pollutants (such as oil spills) being degraded can be described as ___.
Biodegradation.
234
Buffers ___ the pH (combine with H+) of bases to make them more ___.
Increase; basic.
235
What do Gram-negative walls contain?
A thin peptidoglycan layer and a lipopolysaccharide (LPS) outer membrane.
236
What are the subunits and functions of proteins?
Amino acids; enzyme catalyst and structure.
237
What does archaeal flagella get energy from?
ATP.
238
What do high-efficiency particulate air (HEPA) filters do?
Removes nearly all microbes 0.3 micrometers from air.
239
What are 7 factors to consider when selecting the appropriate germicidal chemical?
1. Toxicity.
2. Activity in the presence of organic material.
3. Residues.
4. Compatibility.
5. Cost/availability.
6. Storage/stability.
7. Environmental risk.
240
Chloroplasts are the site of ___ and converts CO2 to ___.
Photosynthesis; sugar and starch.
241
Non-critical instruments/surfaces include ___ and come into contact with ___.
Countertops/stethoscopes/blood pressure cuffs; unbroken skin.
242
Chlorhexidine is a biguanide that is most effective in ___.
Destroying vegetative bacteria, fungi, and some enveloped viruses.
243
A culture in which nutrients are not added and wastes are not removed can be describes as ___.
A closed system (batch culture).
244
Phototrophs obtain energy from ___.
Light.
245
Why does UV radiation have poor penetrating power?
Thin films/coverings can limit effect and glass and plastics block rays.
246
What do carbohydrates include?
Sugars and starches; carbon, hydrogen, and oxygen.
247
The time it take for a population to double can be described as ___.
Generation time.
248
The process of delaying spoilage of perishable products by adding bacteriostatic preservatives can be described as ___.
Preservation.
249
Selective media ___ the growth of certain species and ___ growth of other species.
Inhibit; allow.
250
Chemical preservatives ___and extend shelf-life.
Prevent/slow microbial growth.
251
Catalase is produced by ___
Converting H2O2 to O2 and H2O.
252
What do chemostats do?
Provide an open system that can maintain continuous growth.
253
A two-part covered container of glass/plastic that allows air to enter, but excludes contaminants, can be described as ___.
Petri dish.
254
What does hot air do and what is it used for?
Destroys cell components and denature proteins; used for glass, powders, oils, and dry materials.
255
What is the difference between anions and cations.
A*n*ions are negatively charged (gained electrons) and ca*t*ions are positively charged (lost electrons).
256
What are Father Spallanzani's studies and contributions?
(HINT: think glass blowing.)
He studied the exposure of air and microorganism contamination of broth. He sealed the necks of flasks containing broth. Sealed flasks didn't grow microorganisms, but unsealed flasks did.
257
The converting of N2 gas to ammonia then incorporating it into organic compounds can be described as ___.
Nitrogen fixation.
258
The theory that ancestors of mitochondria and chloroplasts were bacteria residing in other cells can be described as the ___.
Endosymbiotic theory.
259
Low-level disinfectants destroy ___ and are used on ___.
Fungi, enveloped viruses, and vegetative bacteria (not Mycobacteria and non-enveloped viruses); furniture, floors, and walls.
260
Phagocytosis is used by ___ where pseudopods surround and bring material into ___.
Protozoa; phagosomes.
261
What is an atom and what is it made of?
Atoms are the basic unit of life and are made of protons, neutrons, and electrons.
262
List the characteristics of Eukarya.
1. Cell type: ___.
2. # of cells: ___.
3. Membrane-bound organelles?: ___.
4. Unique ribosomal RNA sequences?: ___.
5. Peptidoglycan?: ___.
6. Size: ___
1. Eukaryotic.
2. Uni/multicellular.
3. Yes.
4. Yes.
5. No.
6. 5-50nm.
263
The total number of living and dead cells is the ___.
Direct cell count (microscopic count).
264
And antimicrobial chemical dissolved in alcohol can be described as a ___.
Tincture.
265
What are energy sources and size range of algae?
1. Use sunlight for energy.
2. Microscopic (single-celled algae) and macroscopic (multicellular algae).
266
How does the electron transport chain (ETC) function?
Uses energy from electrons to move protons out of the cell (proton motive force).
267
Polar substances are hydro___ and non-polar substances are hydro___.
Philic; phobic.
268
Water treatment facilities ensure drinking water is free of ___.
Pathogens using chlorine.
269
Thermophiles (45 C - ___) are common in ___.
70 C; hot springs and compost heaps.
270
Heterotrophs use ___ and autotrophs use ___ as CO2.
Organic carbon; inorganic carbon.
271
Protozoa and animal cells lack ___.
Cell walls.
272
What are examples of carbohydrates?
Ribose, deoxyribose, glucose, galactose, mannose, and fructose; sucrose, lactose, and maltose; chitin, agar, cellulose, staton, glycogen, and dextran.
273
What is the function of carbon, hydrogen, and oxygen?
Components of amino acids, lipids, nucleic acids, and sugars.
274
What does irradiation is electromagnetic radiation and includes?
Radio waves, microwaves, visible/UV light, X-rays, and gamma rays.
275
The cell membrane has a ___ model.
Fluid mosaic.
276
What does NAM stand for?
N-acetylmuramic.
277
The coccus shape of a cell is ___.
Round.
278
Antiseptic technique is used to ___.
Prevent contamination of samples, workers, and environment.
279
Bacteria move toward ___ chemotaxis and away from ___ chemotaxis.
Nutrient; toxin.
280
The total genetic content of the microbial community is called a ___.
Microbiome.
281
Nitrate/nitrite inhibit ___.
Endospore germination and vegetative cell growth.
282
What is the function of proteins in the outer layer of the membrane?
Communication receptors and bind ligands.
283
What is a polypeptide?
An alternating series of NAM and NAG to form glycan chains linked together tetrapeptide.
284
How are amino acids structured?
Central carbon, a carboxyl group, and an amino group with an R group.
285
What are unsaturated fatty acids?
Oils; has double bonds.
286
What happens in the lag phase?
Cells being synthesizing enzymes required for growth but the number of cells does not increase.
287
Microbiology was started in the year ___.
1674.
288
Microaerophiles require ___.
Lower O2 concentrations.
289
UV radiation destroys ___ in/on ___.
Microbes; air, water, and surfaces.
290
What are the steps of acid-fast staining? (Used to detect organisms not readily able to take up dyes.)
1. Primary stain is a concentrated red dye.
2. Acid-fast retains red dye after being flooded with acid-alcohol.
3. Methylene blue is used as a counterstain.
291
What are the benefits of heat treatment?
Reliable, safe, fast, inexpensive, non-toxic, and sterilizes/disinfects.
292
What does HAI stand for?
Healthcare-associated infections.
293
How does simple staining work?
Basic dyes are positively charged and attracted to negatively charged cellular components.
294
Explain the hydrogen bonds of liquid H2O.
The bonds constantly form and breaks so molecules easily slide over each other.
295
What is the function of nitrogen?
Component of amino acids and nucleic acids.
296
What are the general rules of the Binomial System of Nomenclature?
It is a two-part name with the format of "[Genus] [species]". The written form is italicized or underlined and only the genus can be abbreviated.
297
How many microbes can be cultured?
Less than 1%.
298
What are some characteristics of Archaea?
1. Single-celled prokaryotes.
2. Lack peptidoglycan.
3. Many are extremophiles.
4. Common in moderate environments.
299
Alcohols denature/damages ___ and are more soluble in water so pure alcohol is ___.
Proteins/membranes; less effective.
300
Buffers ___ the pH (release H+) of bases to make them more ___.
Decrease; acidic.
301
The bacillus shape of a cell is a ___.
Rod.
302
What are the 5 nucleotides?
Adenine (A), Thymine (T), Cytosine (C), Guanine (G), and Uracil (U).
303
Archaea lack peptidoglycan but instead have what?
Pseudopeptidoglycan and self-assembling S layers built from sheets of flat protein or glycoprotein subunits.
304
Chromosomes form a gel-like region called a ___.
Nucleoid.
305
What is the key characteristic of prokaryotes?
No membrane-bound organelles.
306
Fungal cell walls contain ___ and plant cell walls contain ___.
Chitin; cellulose.
307
What is the function of iron?
Part of certain ezymes.
308
A culture to which nutrients are continually added and wastes are removed is described as an ___.
Open system.
309
Name 3 non-human populations influenced by infectious diseases.
1. Irish potato famine (potatoes).
2. English foot-and-mouth disease (pigs, sheep, cattle).
3. "Wheat Blast" (wheat).
310
Ionizing radiation (___) directly destroys ___ and damages cytoplasmic membranes.
Gamma/X-rays; DNA.
311
What is the secondary structure of polypeptides?
Coiling (helix) or folding (pleated sheet) due to hydrogen bonds.
312
Thermostability comes from the ___.
Amino acid sequence.
313
Pseudomonas are resistant to and can grow in ___.
Disinfectants.
314
What are John Tyndall's studies and contributions?
He worked on proving Pasteur correct. He found that sterilization times differ and that hay contained heat-resistant microbes.
315
What is magnification?
A visible increase in the size of an image.
316
What is the function of potassium, magnesium, and calcium?
Required for the functioning of certain enzymes.
317
Description: What is the endoplasmic reticulum (ER)?
A system of flattened sheets, sacs, and tubes.
318
The vibrio shape of a cell is ___
Bent.
319
The coccobacillus shape of a cell is a short ___.
Round rod.
320
What infectious diseases have been reduced since modern sanitization, vaccination, and antibiotics?
Polio, smallpox, and plague.
321
Critical items include ___ and come into contact with ___.
Needles/scalpels; tissues.
322
Peroxygens are powerful ___ used as sterilant that are readily biodegradable with no residue and are ___ toxic than ethylene oxide and glutaraldehyde.
Oxidizers; less.
323
Plasmids have a similar structure to chromosomes, but ___.
Do not encode essential genetic information.
324
High-level disinfectants destroy ___ and use ___.
Viruses/vegetative cells (not endospores); semi-critical instruments.
325
Reducing the available water is accomplished by ___.
Salting, adding sugar, or drying food.
326
What are "animalcules"?
Bacteria and protists.
327
Chemical additives are used to ___.
Prevent spoilage.
328
What are the element of living matter?
(HINT: CHONPS.)
Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, and Sulfur.
329
A two-cell chain is described as a ___.
Diplococci.
330
What are the subunits and functions of RNA?
Ribonucleotides; protein synthesis.
331
The spirillum shape of a cell is ___.
Curvy.
332
What are Hans Christian Joachim Gram's studies and contributions?
He invented the Gram stain (leading to the terms Gram-positive and -negative) when staining a culture and one part of the culture retained the dye while the other didn't, revealing two kinds of bacteria.
333
Irradiation and high pressure are used to ___.
Treat certain foods without altering it.
334
What is the function of the Golgi Apparatus?
Modifies synthesized macromolecules in the ER.
335
MacConkey agar is selective for ___ rods and contain ___ that inhibits ___ bacteria and bile salts that ___ most non-intestinal bacteria.
Gram-negative; crystal violet; Gram-positive; inhibit.
336
The reduction of pathogens to a safe level by means of washing, use of heat, and chemicals can be described as ___.
Decontamination.
337
What are the subunits and functions of carbohydrates?
Monosaccharides; structural component and energy storage.
338
Differential media contain a substance that microbes ___.
Change in an identifiable way.
339
A single cell fives rise to a colony and the number of colonies reflects how many cells are in a sample can be described as ___.
Plate count.
340
What is a hydrogen bond?
A weak bond formed when a hydrogen from a polar molecule is attracted to an electronegative atom from the same or other polar molecule.
341
What is the quaternary structure of polypeptides?
Association between multiple polypeptides.
342
Most obligate aerobes and facultative anaerobes can be ___.
Incubated in air (~20% O2).
343
What are Robert Hooke's studies and contributions?
(HINT: another word for microorganisms.)
Discovered microbes and described "microscopical mushrooms."
344
Why are microbes good research tools?
1. Cells have the same chemical elements.
2. Cell structures synthesize by similar mechanisms.
3. DNA duplication.
4. Same metabolic pathways to degrade foods.
345
Boiling destroys most microorganisms/viruses but does not ___.
Sterilize and endospores survive.
346
Hyperthermophiles (___) are usually archaea and found in ___.
>70 C; hydrothermal vents.
347
What is the difference of the atomic number and the mass number?
The atomic number is the total of ONLY protons and the mass number is the total of protons and neutrons.
348
The rough ER is dotted with ribosomes and functions in ___ while the smooth ER functions in ___.
Protein synthesis; lipid synthesis, degradation, and calcium storage.
349
Halophiles require ___.
High salt concentrations.
350
Low-temperature storage inhibits growth of ___ by slowing/stopping ___.
Pathogens and spoilage organisms; enzyme reactions.
351
What were the results of Francesco Redi's studies on worms and rotting meat?
The jar that was covered (no access to flies) never had worms on the meat. *SPONTANEOUS GENERATION DISPROVEN*
352
What are the subunits and functions of DNA?
Deoxyribonucleotides; carries genetic information.
353
Fastidious species can be used to ___.
Measure the quantity of vitamins in food products.
354
Sporulation is triggered by ___.
Limited carbon and nitrogen.
355
What is the basis of the Human Microbiome Project of 2007?
DNA sequencing was used to characterize microbial communities of the human body.
356
What do proteins serve as in cells?
Selective gates, sensors of environmental conditions, and enzymes.
357
The principle that microorganisms cause disease can be described as ___.
The Germ Theory of Disease.
358
Positive charges of quats are attracted to ___ of the cell surface and reacts with the membrane and destroys ___.
Negative charges; vegetative bacteria and enveloped viruses.
359
What is a chromosome?
A single circular double-stranded DNA molecule packed tightly via binding proteins and supercoiling.
360
What are normal microbiota?
Natural populations of microorganisms on your body.
361
What are some food production benefits of microorganisms?
1. Yeast is used to make bread.
2. Beer is made from grain fermentation.
3. Fermented milk is yogurt, cheese, etc.
362
What were John Needham's findings?
Boiled broths still produced microorganisms.
363
What is the primary structure of polypeptides?
Sequence and number of amino acids.
