Final exam Flashcards
1
Q
6 groups of microbes
A
Bacteria
Archaea
Fungi
Protozoan
Algae
Small multicellular animals
2
Q
Bacteria
A
Unicellular, prokaryote
Cell wall composed of peptidoglycans
- Requires sufficient moisture
- Obtains energy through organic molecules or photosynthesis or inorganic molecules (nitrogen/phosphorus)
3
Q
Archaea
A
Unicellular, prokaryote
Cell wall
- Found in extreme conditions
- Not pathogenic to humans
4
Q
Fungi
A
Unicellular/multicellular eukaryotes
Obtains energy by decomposing dead organisms
Can be pathogenic (ringworm)
ex: Mold (multicellular) and Yeast (unicellular)
5
Q
Protozoa
A
Unicellular eukaryotes
Mobile
Found in water, some live in hosts
AKA: Parasites
Ex: Malaria
6
Q
Algae
A
- Unicellular/Multicellular, eukarytotic
- Photosynthetic (chloroplasts)
- Important in ecology/enviornment
- Not usually pathogenic
7
Q
Algae is not typically _____ but there’s 2 exceptions:
A
Pathogenic
- An immunosuppressed person
- Algae Bloom
8
Q
Small Multicellular Organisms
A
- Multicellular eukaryotes
- Adult worms can be visible to the naked eye, but immature stages are microscopic
9
Q
What are Koch’s Postulates?
A
- Suspected causative agent must be found in every case of the disease & absent in healthy hosts
- Agent must be isolated and grown outside of the host
- When agent is introduced to a healthy, susceptible host, the experimental host must get the disease
- Same agent must be found in the diseased experimental host
10
Q
Pasteur
A
Disproved the idea of spontaneous generation/abiogenesis
Found what caused fermentation; discovered process now called “pasteurization”
11
Q
Lister
A
Antiseptic technique
12
Q
Jenner
A
Responsible for 1st vaccination (against smallpox)
He was aware that infection actually produced immunity
13
Q
Ehrlich
A
Magic bullets (antibiotics)
14
Q
Fleming
A
Discovered the 1st antibiotic to treat disease
15
Q
Nightingale
A
Nursing and hygiene
16
Q
Linneaus
A
Responsible for the binomial system of nomenclature (naming system)
DKPCOF
Genus
Species
17
Q
Leeuwenhoek
A
“Father of Microbiology”
1st to observe live microorganisms (through his magnifying lenses)
18
Q
Abiogenesis
A
Spontaneous generation theory that living things came from nonliving matter
19
Q
Pasteurization
A
Process of heating it just enough to kill spoilage or pathogenic microorganisms.
Doesn’t alter the quality of food
20
Q
What are the 4 common processes of all living things?
A
Growth
Reproduction
Responsiveness
Metabolism
21
Q
The cell wall of a gram-positive bacteria forms a ____, rigid structure. It has many layers of ________, which refers to a chemical molecule that is part ___ and part _______.
A
The cell wall of a gram-positive bacteria forms a thick, rigid structure. It has many layers of peptidoglycan molecules, which refers to a chemical molecule that is part protein and part polysaccharide
22
Q
Gram-positive bacteria:
The peptidoglycan layer also contains teichoic acid and (1) _____ _____. What does (1)______ ___ do?
A
Lipoteichoic acid
It attaches the cell wall to the cell membrane
23
Q
Gram-positive bacteria:
The ______ part of peptidoglycan consists of long chains of repeating alternating molecules called ___ and ____. The layers are held together by ______ ________.
A
polysaccharide
NAG and NAM
tetrapeptide crossbridges
24
Q
The cell walls of a gram-negative bacteria consist of a ____ ________ ___ surrounded by an outer membrane. Similar to gram-positive bacteria, they have alternating ___ and ____ structures, but they don’t have ______ _____.
A
The cell walls of a gram-negative bacteria consist of a thin peptidoglycan layer surrounded by an outer membrane. Similar to gram-positive bacteria, they have alternating NAG and NAM structures, but they don’t have lipoteichoic acid
25
The outer membrane of a gram-negative bacteria is a _______. Its inner layer is composed of _____ molecules and ____.
The outer membrane of a gram-negative bacteria is a **bilayer** Its inner layer is composed of **phospholipid molecules & proteins**
26
Gram-negative bacteria:
The outer layer of the outer _____ is composed of both phospholipid molecules and ________(___). The lipid portion of LPS is known as _____ __
The outer layer of the outer **membrane** is composed of both phospholipid molecules and **lipopolysaccharide (LPS)**. The lipid portion of LPS is known as **lipid A**
27
Where is lipid A found?
The outer cell membrane of a gram-negative bacteria
28
Lipid A is also called an _______ (this is released when the cell ____ and can cause fever, vasodilation, inflammation, shock, and blood clotting)
Lipid A is also called an **endotoxin** (this is released when the cell **dies** and can cause fever, vasodilation, inflammation, shock, and blood clotting)
29
Tetrapeptide cross-bridges connect..
NAM to NAM
30
3 appendages can be found on the exterior of bacterial cell walls:
Flagella, Fimbriae, Pili
31
Flagella
- Used for movement
- Basal body attaches hook to a cell wall and cell membrane
32
Flagella arrangements
Monotrichous: one
Amphiritichous: two on opposite ends
Lophotrichous: 2+ on the same end
Peritrichous: all around/surrounding
33
Fimbriae and pili are both used for _____ and are made up of protein molecules called ____. What's the difference between the two?
Fimbriae and pili are both used for ATTACHMENT and are made up of protein molecules called PILINS.
Pili attachment is for a specific purpose called conjugation.
34
Types of movement for flagella
Runs (propels foward): counterclockwise
Tumbles: Clockwise
35
How are ribosomes different in prokaryotes and eukaryotes
Bacteria/prokaryotes have 70S ribosomes while eukaryotes have 80S ribosomes (with 70S only being in mitochondria/chloroplasts)
36
Glycocalyx functions
Prevents desiccation (drying out), evade phagocytosis, attachment
37
Glycocalyx are found..
attached to the outermost layer of the cell wall
38
Glycocalyx:
If the sticky substance is ____ and ____ attached to the bacterial cell wall, the glycocalyx is described as a _____
v.s
If the sticky substance is ____ and ____ attached to the bacterial cell wall, the glycocalyx is described as a _____
Organized and firmly attached = capsule
Unorganized and loosely attached = slime layer
39
The outer cell membrane of bacteria is made up of a cholesterol-like molecule called a
Hoponoid
40
4 comparisons between bacterial (prokaryotic) and eukaryotic cells
Bacteria:
No nucleus
Flagella rotate
Cell walls (present in most) contain peptidoglycans
Endospores are present in some
Eukaryotes:
Nucleus
Flagella undulate
Cell walls- present in plants, algae, and fungi- NO peptidoglycans
No endospores
41
LPS is made up of
a lipid on one end and polysaccharide on the other
42
Endospores are considered the _________________________ to ______. Many endospores produce toxins that can cause fatal diseases such as ____ and ____.
most difficult biological structure to destroy
anthrax and tetanus
43
Found in the _______ of some bacteria are endospores, which are used as a ________ strategy against ______ _____, such as when nutrients (especially ___ and ___) are exhausted or if there isn't sufficient _____.
Found in the CYTOPLASM of some bacteria are ENDOSPORES which are used as a DEFENSE strategy against UNFAVORABLE CONDITIONS, such as when nutrients (especially Carbon and Nitrogen) are exhausted or if there isn't sufficient MOISTURE.
44
Where are endospores found?
Cytoplasm
45
Endospores are formed by a process called _____ which takes between 8-10 ____. Endospores can remain dormant for thousands of years and when conditions become ___ for growth, endospores ___ to produce new _____ ___ (cells that grow and reproduce).
Endospores are formed by a process called SPORULATION which takes between 8-10 HOURS. Endospores can remain dormant for thousands of years and when conditions become FAVORABLE for growth, endospores GERMINATE to produce new VEGETATIVE CELLS
46
If the color is in the positive ion, these stains are known as
basic dyes
47
If the color is in the negative ion, these stains are known as
acidic dyes
48
Bacterial cells are slightly negatively charged. Based on this information, what type of dye is best used to view bacteria?
basic dyes
49
Since acidic dyes carry negative electric charges, and bacteria cells are also negative, they are not ____ to bacterial cells. As a result, it can't stain the bacterial cells and instead stains the ________
Since acidic dyes carry negative electric charges, and bacteria cells are also negative, they are not **attracted** to bacterial cells. As a result, it can't stain the bacterial cells and instead stains the **background**
50
The procedure of a gram stain
1. _______(a basic dye w purple color) is applied and is referred to as a _____
2. Rinsed off the slide with water
3. Slide is then covered with ____, which is a ______ (purpose is to _______)
4. Next, the slide is washed with ____, a _____ ____. This breaks down the ____ of gram ______ cells.
5. It's then rinsed off the slide with water, and the slide gets stained with ____ (a basic dye with red color). _______ is referred to as a _________ because it has a contrasting color to the primary stain.
1. CRYSTAL VIOLET (a basic dye w purple color) is applied and is referred to as a PRIMARY STAIN
2. Rinsed off the slide with water
3. Slide is then covered with IODINE, which is a MORDANT (purpose is to INTENSIFY the color of the primary stain)
4. Next, the slide is washed with ALCOHOL, a DECOLORIZING AGENT. This breaks down the cell wall of gram-NEGATIVE cells.
5. It's then rinsed off the slide with water, and the slide gets stained with SAFRANIN (a basic dye with red color). SAFRANIN is referred to as a COUNTERSTAIN because it has a contrasting color to the primary stain.
6. The slide is rinsed with tap water, blotted dry, and observed under the microscope.
51
After the primary stain (_____) and the mordant (____) are used...
(crystal-violet)
(iodine)
all cells are stained purple
52
After the decolorizing agent (____) is used, it removes the _____ ___ from ONLY the ______ ____ _____, making the _____ ______ become ______
alcohol
purple color
gram-negative bacteria (2x)
become colorless
53
After staining with a counterstain (_____), it turns the ______ gram-____ bacteria ____. Since the gram-____ bacteria retained the original _____ color, they are ___ _______ by the counterstain
After staining with a counterstain (SAFRANIN), it turns the COLORLESS gram-NEGATIVE bacteria PINK. Since the gram-POSITIVE bacteria retained the original PURPLE color, they are NOT AFFECTED by the counterstain.
54
Acid-Fast Stain
Used for bacteria that have waxy cell walls
Ex: Mycobacterium and Nocardia
55
Metabolic reactions usually involve the movement of electrons (which are ________ of _____). The molecule that is oxidized is the one to _____ the electron and involves _____. The molecule that is reduced ______ the electron and involves _____.
Metabolic reactions usually involve the movement of electrons (which are **carriers of energy**). The molecule that is oxidized is the one to **donate** the electron and involves **loss**. The molecule that is reduced **accepts** the electron and involves **gain**
56
Phosphorylation is when
ATP is regenerated/recycled from ADP and Pi (inorganic phosphate)
57
3 ways phosphorylation can be accomplished:
(basically, who provides the energy for the third phosphorus? ADP + P ---> ATP)
- Substrate-level phosphorylation
- Oxidative phosphorylation
- Photophosphorylation
58
transfers Pi from an organic molecule
(the bond gets broken)
Substrate-level phosphorylation
59
Using energy from the redox reaction to add Pi
(there's no bond to be broken)
Oxidative phosphorylation
60
Using light energy to add Pi
(no bond broken)
Photophosphorylation
61
The overall process of cellular respiration can be summarized as
Glycolysis
Krebs Cycle
Electron Transport Chain
62
Glycolysis starting molecule:
ending molecule:
starting: Glucose
ending: Pyruvic Acid
63
What carrier molecule is used during Glycolysis and how many?
NADH, 2
64
How much ATP is used in Glycolysis? How much is produced? Net amount?
2 ATP is used
4 ATP is produced, 2 net
65
Summary of Metabolic Stages:
Glycolysis:_______---> ______
The Preparation stage: _____---> ______
The Krebs Cycle: _______---> ______
The Electron Transport Chain: once ______ _____ electrons, it is _____ to form ____
Glycolysis: 1 glucose molecule --> 2 pyruvate molecules
The Preparation stage: each pyruvate molecule---> acetyl CoA molecule
The Krebs Cycle: each acetyl CoA ---> CO2
The Electron Transport Chain: once **oxygen accepts electrons, it is reduced to form H20**
66
Summary of Energy Yielded:
Glycolysis:
The Preparation Stage:
The Krebs Cycle:
The Electron Transport Chain:
Total:
Glycolysis: 2 ATP, 2 NADH
The Preparation Stage: 2 NADH
The Krebs Cycle: 2 ATP, 2 FADH2, 6 NADH
The Electron Transport Chain: 34 ATP
Total: 38 ATP molecules per glucose molecule
67
Each molecule of pyruvate coming from glycolysis must first be converted to another chemical called_______
acetyl coenzyme A (acetyl CoA)
68
Key concepts of the Krebs Cycle:
Starting molecule?
How many molecules of ATP?
What method of phosphorylation?
How many molecules of FADH2?
How many molecules of NADH?
How many molecules of CO2?
Starting molecule?
Acetyl-CoA
How many molecules of ATP? 2
What method of phosphorylation? Substrate level phosphorylation
How many molecules of FADH2? 2
How many molecules of NADH? 6
How many molecules of CO2? 4
69
What method of phosphorylation occurs in the Electron Transport Chain?
Oxidative phosphorylation
70
Electron Transport Chain:
Each NADH creates __ __
Each FADH creates __ __
In total, there are ___ ATP molecules that can be generated from one ____ ____
3 ATP
2 ATP
34 ATP
glucose molecule
71
Electron transport chain:
In aerobic respiration, ____ is the final electron acceptor. In anaerobic respiration, it's an ______ _____ that acts as the final electron acceptor
Oxygen
Inorganic molecule
72
2 main pathways of energy production
cellular respiration
fermentation
73
Only ____ leads to fermentation, not ____
Only **yeast** leads to fermentation, not **bacteria**
74
End products of fermentation
Lactic acid and ethanol
75
How much ATP does fermentation produce?
2 atp
76
When does fermentation occur?
When there is an absence of final electron acceptors (no oxygen, no inorganic molecule)
77
What acts as a final electron acceptor in fermentation?
Pyruvic acid
78
Metabolism is divided into two types of chemical reactions:
What's the difference between these two?
Catabolic: breaks down large molecules into smaller products, **exergonic** (releases energy), ex: proteins --> a.a
Anabolic: turns smaller products into large molecules, requires energy to make bonds (**endergonic**), ex: a.a---> protein or fatty acid --> lipid
79
To move the electrons around (for oxidation-reduction reactions), a carrier is often used. The important ones are:
The electron is usually associated with a _______ atom since it only has _____ ______. So the carriers pick up and drop off the _____
NAD+
NADP+
FAD
The electron is usually associated with a HYDROGEN atom since it only has ONE ELECTRON. So the carriers pick up and drop off the HYDROGENS.
80
Apoenzyme
The name of the protein portion when the enzyme is combined with other molecules
81
The apoenzyme is ____ if not bound to nonprotein ______
inactive
cofactors
82
Cofactors are ____ molecules, like ___ or ___. If the cofactor is an ______ molecule, it's called a _____.
Cofactors are INORGANIC molecules, like Zn or Fe. If the cofactor is an ORGANIC molecule, it's called a COENZYME
83
Important coenzymes:
NAD
FAD
CoA
84
Holoenzyme
Yields from when apoenzyme binds with its cofactors/coenzymes
85
3 basic requirements that all cells need for metabolism:
a carbon source, an energy source, and an electron source
86
Carbon sources and where they get their energy from
Autotrophs- CO2
Heterotrophs- organic
87
Energy sources and where they get their energy from
Chemotrophs- organic
Phototrophs- light
88
Electron (H) sources and where they get their energy from
Organotrophs- organic
Lithotrophs- inorganic
89
Plants and algae are considered
photoautotrophic (CO2 and light)
90
Humans, bacteria, animals, fungi, etc. are considered
chemoheterotrophs (both organic)
91
Obligate aerobes
Requires oxygen to live and grow
Oxygen is used as the final electron acceptor when making energy
92
Obligate anaerobes
Unable to use oxygen for growth because it lacks enzymes (like catalyse)
Oxygen can actually be toxic for them
93
Facultative anaerobes
Prefers oxygen, but can survive without it
94
Aerotolerant anaerobes
Has small levels of enzymes but doesn’t use oxygen
Prefers no oxygen but will tolerate it
95
Microaerophiles
able to survive with low levels of oxygen
96
Nitrogen Fixation- what is it and why is it important?
When microbes are able to convert the nitrogen in the air (N2) into NH3
This is essential since it’s providing a usable form of nitrogen for other organisms to use
97
Complex media
Most common, generalized (so most bacteria grow well in complex media)
**Ex: Nutrient agar and tryptic soy agar (TSA)**
98
Enriched media is also generalized, but with an added ingredient: blood. Enriched media is used to encourage the growth of a particular bacteria species of interest. It’s typically used to cultivate bacteria from samples such as:
blood, urine, and sputum
99
Examples of selective media
Sabouraud dextrose agar
MacConkey agar
EMB agar (Eosin-methylene blue agar)
HE agar (Hektoen enteric agar)
100
Examples of differential media:
MacConkey agar
HE agar
Blood agar
101
Sabouraud dextrose agar only selects for
the growth of fungi while inhibiting bacterial growth
- supplemented with antibiotics (added ingredient)
102
MacConkey agar only selects for
gram-negative bacteria while inhibiting the growth of gram-positive bacteria
103
What inhibits the growth of gram-positive bacteria for MacConkey agar?
Both bile salts and crystal violet
104
EMB agar only selects for
the growth of gram-negative bacteria while inhibiting the growth of gram-positive bacteria
105
What inhibits the growth of gram-positive bacteria for EMB agar?
Eosin and methylene blue
106
HE agar selects for
the growth of gram-negative bacteria ONLY while inhibiting the growth of gram-positive bacteria due to its chemical ingredients
107
What ingredient inhibits gram-positive bacteria for HE agar?
only bile salt
108
MacConkey agar differentiates whether the bacteria can _______ ______. What color change occurs?
ferment lactose = turns pink (G-)
do not ferment lactose = cream (G-)
109
HE agar differentiates based on
lactose fermentation and sulfur utilization
110
What color does lactose-fermenting gram-negative bacteria turn on HE agar?
What about non-lactose fermenting gram-negative bacteria?
1. salmon-orange
2. retains blue-green color
111
HE agar can differentiate bacteria based on their ability to utilize ____. When hydrogen sulfide reacts with iron, it forms ____ ____ on the HE agar.
sulfur
black precipitates
112
Eosin-Methylene blue is both a selective and differential media. It assesses for lactose fermentation: positive will look ____/____/metallic while negative will have ___ ____/media
positive will look **purple/black/metallic** while negative will have **no color**/media
113
What is a biofilm?
A complex relationship among numerous microbes
114
Binary fission steps:
Chromosome _____ (attaches to cell membrane)
Cell ______, ______chromosome
____ cell wall/cell membrane form ____
____ is completed, separating into___ _____ microbes.
Chromosome REPLICATES (attaches to cell membrane)
Cell ELONGATES, SEPARATING chromosome
NEW cell wall/cell membrane form SEPTUM
SEPTUM is completed, separating into 2 IDENTICAL microbes.
115
4 phases of bacterial growth
lag phase
log phase
stationary phase
death phase
116
Lag Phase
- Little change in # of microbes
- Adapting to environment
- Lasts hours to days
117
Log Phase
- Exponential growth (2^n)
- Cells most active
- Best time to gram stain
- Best time to assess effectiveness of antibiotics
118
Stationary Phase
- Growth slows
- Deaths = divisions- equilibrium
119
Death Phase
- Deaths > divisions
- Accumulation of wastes, depletion of nutrients, change in pH
120
3 groups based on the preferred temperature of a microbe
Which is most likely to be pathogenic and why?
Psychrophiles- likes cold
Mesophiles- in between
Thermophiles- likes heat
Mesophiles because they like human temperatures the best
121
Care must be taken when culturing a microorganism otherwise contamination may occur. The goal is to culture an Axenic culture. What does axenic mean?
Pure
122
Control plate and nothing grows on it
axenic and aseptic
123
Control plate has growth, but only one species of bacteria is growing:
axenic but not aseptic
124
Fastidious bacteria are
hard to grow
125
Quorum sensing in a biofilm is responsible for what 4 things?
- Communication between microbes
- Able to determine population and species of microbes
- Helps to control certain genes within each microbe
- Microbes assume specific functions to benefit community
126
Blood agar differentiates bacteria based on red blood cell _____, in other words, whether or not a bacteria can _____ (break down) red blood cells.
hemolysis
hemolyze
127
Alpha-hemolysis
partially hemolyze (green/gray media)
128
Beta-hemolysis
completely hemolyze
(clear)
129
Gamma-hemolysis
unable to hemolyze (no change)
130
Basically, with each division of binary fission, the population ____. This is represented as __ (indicates _____ growth)
n = generation
Basically, with each division of binary fission, the population **doubles**. This is represented as **2^n** (indicates **exponential** growth)
n = generation
131
Generation Time
The time required for a bacterial cell to double (divide)
Most have a doubling time of 1-3 hours
132
What is a plasmid?
a small DNA molecule that replicates independently of the other chromosomes often carrying information required for replication.
133
4 different types of plasmids
Fertility
Resistance
Bacteriocin
Virulence
134
Fertility
instructions for conjugation
135
Resistance
antibiotic resistance
136
Bacteriocin
kills competitors
137
Virulence
enzymes/toxins that enable pathogenicty
138
Plasmids do not ________________
Plasmids do not control normal metabolism
139
Operons are composed of a
a **Promoter, a series of genes**, and an adjacent regulatory element called an **operator**.
140
The operator is important in determining when the operon is ______ ______ ______
actively producing proteins
141
To start making any gene, you need a
promoter
142
The regulatory gene controls the _____ and needs a _____ to start
operator, promoter
143
The operator controls the _____
operon
144
Lac Operon:
-______, turns __ when conditions are right
-Operon is normally ___ at all other times due to the production of a _______ ____
-Repressor protein blocks the _____
-When lactose is present, the bacteria can now ______ it
-Lactose is converted to ______
-________ _______ ___ ______ _____
-_______ of the lac operon can now occur
-**Inducable**, turns **on** when conditions are right
-Operon is normally **off** at all other times due to the production of a **repressor protein**
-Repressor protein blocks the **operator**
-When lactose is present, the bacteria can now **catabolize** it
-Lactose is converted to **allolactose**
-**Allolactose inactivates the repressor protein**
-**Transcription** of the lac operon can now occur
145
Tryptophan Operon:
-_______: turns __ when conditions are favorable
-Operon is normally __, allowing bacteria to make its own tryptophan
-Repressor protein is made continuously but is normally _____
-When _______ is in the environment the repressor is ______
-Turns ___ the _____
**Repressible**: turns **off** when conditions are favorable
-Operon is normally **on**, allowing bacteria to make its own tryptophan
-Repressor protein is made continuously but is normally **inactive**
-When **tryptophan** is in the environment the repressor is **activated**
-Turns **off** the **operon**
146
Transmission in which the bacteria acquire new genes from the same generation which it can then now pass on to the next generation vertically (gives to their ‘friends’)
Horizontal transmission
147
3 methods of horizontal transmission:
Transformation
Transduction
Conjugation
148
Transformation is …
The bacteria capable of this are called _____
Absorption of DNA from the environment
The bacteria capable of this are called **competent**
149
Transduction
A replicating virus, (called a **Bacteriophage-the general term for a virus that attacks the prokaryote**), transmits DNA from one cell that is picked up to another
150
Conjugation
-Uses ___ ___
-_____ ___ can be associated with __ ____ OR gene can be _______ ___ ___ ______ (called ___)
-Uses sex pilus
-Fertility gene can be associated with F plasmid OR gene can be integrated into the chromosome (called Hfr)
151
Operons that turn genes on in response to changes in the environment are categorized as:
Inducable
152
Operons that turn genes off in response to changes in the environment are categorized as:
Repressible
153
Physical Methods of Microbial control
Moist Heat
Dry Heat
Low Temperature
Desiccation
Filtration
Osmotic Pressure
Radiation
154
Chemical Methods of Microbial control
Phenolics
Halogens
Alcohols
Heavy Metals
Surfactants
Oxidizing Agents
155
Sanitation
Reducing the # of pathogens
156
Sterilization
The removal of all microorganisms, including endospores
157
Disinfection
A chemical treatment to kill/inhibit growth on inanimate objects
158
Degerming
The mechanical removal of most of the microorganisms in a limited area by scrubbing
159
Phenolics
- Denatures proteins and disrupts the cell membranes
- Triclosan: phenol and phenolics
- Found in garbage and diapers
160
Alcohols
- Kill bacteria and fungi but not endospores
- Denatures proteins and disrupts plasma membrane
161
Halogens
- Damages proteins with denaturation
- Iodine (oldest/most effective antispetic)
- Chlorine (disinfects water, present in bleach)
- Flouride (toothpaste)
- Bromine (hot tubs)
162
Surfactants-3 types
Soap
Acid-anionic detergents
Cationic detergents
163
Surfactants-mechanism of action
Disrupts cell membrane
164
Quats are considered a _____ ______. What do Quats do?
1. Cationic detergent
2. They disrupt the cell membrane and is bacteriocidal except for endospores
165
Other than endospores, what else can Quats not destroy and why?
Mycobacteria due to the waxy cell membrane
166
Static
inhibits growth but does not kill the microbe
167
Cidal
kills the microbe
168
Selective Toxicity (2 things about it)
- Drug will only affect microorganisms without damaging human
- Mechanism of action will affect cell structure or metabolism but not both
169
5 ways an antimicrobial drug can work:
1. The inhibition of cell wall synthesis
2. The inhibition of protein synthesis
3. Disruption of the plasma membrane
4. Inhibition of nucleic acid synthesis
5. Inhibiting metabolic pathways
170
All penicillins have a _____ _____ structure containing a _____ _____ _____. So, _____ _____ are..
All penicillins have a **common core** structure containing a **beta-lactam ring**. So, **beta lactams are inhibitors of cell wall synthesis**
171
Examples of beta-lactams
Penicillin, Penicillin derivatives, and Cephalosporins.
172
Chloramphenicol side effect:
bone marrow suppression
173
Aminoglycoside side effects
- Ototoxic (deafness)
- Nephrotoxic (kidneys)
174
Tetracyclines side effect:
Teeth discoloration
175
Azole side effect
Hepatotoxic (liver)
176
Macrolides side effect:
Heart
177
Inhibiting metabolic pathways:
In order to produce DNA/RNA, bacteria need _____ _____. ____ disrupts DNA/RNA _______, but humans ______________
Bacteria need folic acid
- PABA
- Humans do not use PABA and therefore have minimal toxicity to these medications
178
Ergosterol: similar in composition to ________ which is found in _____-_____ bacteria
similar in composition to **cholesterol** which is found in **gram negative** bacteria
179
Multiple resistance is often referred to as a
Superbug
180
Resistance to many drugs simultaneously
Multiple resistance
181
Cross-resistance
resistance to drugs of similar action
182
The use of antibiotics has not _____ resistance but rather has ______ for it
The use of antibiotics has not **produced** resistance but rather has **selected** for it
183
Which spectrum of action may allow for secondary or superinfections
Broad
184
When a virus particle is located _______ (outside a cell) it is comprised of 2 basic components: a protein coat called a _____ which surrounds a ______ _____ core. There may be a third component, a phospholipid membrane called an ______, surrounding the capsid.
When a virus particle is located **extracellularly** (outside a cell) it is comprised of 2 basic components: a protein coat called a **CAPSID** which surrounds a **nucleic acid core**. There may be a third component, a phospholipid membrane called an **ENVELOPE**, surrounding the capsid.
185
The capsid is composed of protein subunits called ______. The capsomeres are arranged in different ways creating three basic viral shapes. These are:
The capsid is composed of protein subunits called **CAPSOMERES**. The capsomeres are arranged in different ways creating three basic viral shapes. These are:
1. Helical
2. Polyhedral
3. Complex
186
General pattern of a typical virus life cycle:
1. Attachment
2. Entry of nucleic acids/enzymes
3. Synthesis of new nucleic acids and capsids
4. Assembly
5. Release
187
The general pattern is called ____ _____
Lytic replication
188
Some viruses, once intracellular, go into a period of ____ where they remain ____ only to surface at a later date.
Some viruses, once intracellular, go into a period of LATENCY where they remain DORMANT only to surface at a later date.
189
Where does the life cycle get altered with latency?
A pause occurs between entry and synthesis
1. Attaches
2. Enters
3. Pauses
4. Synsthesis
5. Assembly
6. Release
190
Latency is often represented by the ______ _____
Lysogenic replication
191
Prions are a proteinaceous agent and are considered _____ ____ that cause neurologic lesions in ____ ____
Prions are a **proteinaceous agent** and are considered **infectious proteins** that cause neurologic lesions in **multiple species**
192
Prions:
- ___ _______
- Can only be destroyed by ______
- Cause for disease development:
- Any pattern to age?
- Any pattern to symptoms?
- **No treatment**
- Can only be destroyed by **incineration**
- Cause for disease development: **inheritance or ingestion**
- Any pattern to age? **age-related, 50**
- Any pattern to symptoms? **amyloid plaques/ death**
193
The prion converts normal ___ cellular PrP into __ (bad). Ultimately, prions ____ _____
The prion converts normal **alpha** cellular PrP into **beta** (bad). Ultimately, prions **don't replicate**
194
T/F- Prions replicate very slowly
False, they don't replicate!
195
Resident microbiota
- Been there since we were born
- Harmless under normal conditions (non-pathogenic)
196
Transient Microbiota are only _____ and do not persist in body due to 3 things:
temporary
1. Elimination by body's defense cells
2. Hygiene
3. Competition from other microbe
197
Commensalism
Benefits microbe, no harm to host
Ex: mites on eyelashes
198
Mutualism
Benefits microbe, benefits the host
Ex: E.coli
199
Parasitism
Benefits microbe, harms the host
Ex: tapeworm
200
There's an offset of parasitism called _____ in which there is..
Amensalism: no benefit to microbe, but the host is still harmed
201
If the pathogenic microorganism is not a normal microbiota the question is where is the pathogen normally found?
Reservoir
202
3 primary reservoirs:
Human reservoir
Animal reservoir
Nonliving/environmental reservoir
203
The majority of infections are from ____ ____ due to
Human reservoirs due to temp. and species specificity
204
There are three types of asymptomatic carriers:
1. Incubation carriers: not yet showing signs
2. Convalescent carriers: active stages of recovery
3. Chronic carriers: recovered but still shedding
205
Types of contact transmission
Direct contact transmission
Indirect contact transmission
Droplet transmission
206
Vehicle Transmission-
Vehicle transmission is the spread of pathogen from its reservoir to the host by a _____, such as..
Vehicle transmission is the spread of pathogen from its reservoir to the host by a **vehicle, such as water, food, or air.**
207
Besides the vehicles that we mentioned above (water, food, or air), blood and other ___ ____ can also serve as a vehicle.
bodily fluids
208
Vector Transmission-
Vectors are referred to animals that carry pathogens from the _____ to the ___. The most important group of disease vectors are _____, such as flies, mosquitoes, fleas, ticks…etc. Some of these arthropods are ______vectors whereas others are ______vectors.
Vectors are referred to animals that carry pathogens from the **reservoir to the host**. The most important group of disease vectors are **arthropods**, such as flies, mosquitoes, fleas, ticks…etc. Some of these arthropods are **mechanical vectors whereas others are biological vectors**
209
Mechanical vectors pick up pathogens on their body parts, such as their feet, and carry them from one place to another. They ____ transmit pathogens present on their body to new hosts. Basically, the pathogens are ___ the bug, not __ it.
Mechanical vectors pick up pathogens on their body parts, such as their feet, and carrying them from one place to another. They **passively** transmit pathogens present on their body to new hosts. Basically, the pathogens are **on** the bug, not **in** it.
210
Biological vectors not only carry pathogens from reservoir to the host, but they themselves have also been _____ with the pathogens. Therefore, the pathogens are ___ the bug, not ___ it. Biological vectors usually transmit pathogens by ____
Biological vectors not only carry pathogens from reservoir to the host, but they themselves have also been **infected** with the pathogens. Therefore, the pathogens are **in** the bug, not **on** it. Biological vectors usually transmit pathogens by **biting**
211
If a person coughs and transmits a microbe through a ventilation system it's ____. However, if they coughed within 3 ft of you, it's _____
Vehicle
Contact
(droplet vs aerosol)
212
List the 5 stages of infectious disease
1. Incubation period
2. Prodromal period
3. Illness
4. Decline
5. Convalescence
213
Describe the incubation period
no signs or symptoms (infected but not affected)
214
Describe the prodromal period
vague, general symptoms
215
Illness
most severe signs and symptoms
216
Decline
declining signs and symptoms
217
Convalescence
no signs or symptoms
218
Most of our Resident Microbiota can actually benefit us by a phenomenon called ______ ______(1)
_____ _____(1) is a way for the members of our Resident Microbiota to protect us from these intruders. Microbial antagonism involves _____ between our Resident Microbiota and the invading pathogens. One consequence of such competition is that our Resident Microbiota can protect the host by ______ any invading pathogens coming from outside the human body from establishing their ______
**Microbial antagonism** is a way for the members of our Resident Microbiota to protect us from these intruders. Microbial antagonism involves **competition** between our Resident Microbiota and the invading pathogens. One consequence of such competition is that our Resident Microbiota can protect the host by **preventing** any invading pathogens coming from outside the human body from establishing their **residence**
219
Resident Microbiota normally __ ___ cause disease.
But under certain conditions, some members of our Resident Microbiota can become harmful and cause disease when the proper “_______” arises. These microorganisms are known as _______ _____
Resident Microbiota normally **do not** cause disease.
But under certain conditions, some members of our Resident Microbiota can become harmful and cause disease when the proper **“opportunity”** arises. These microorganisms are known as **opportunistic pathogens**.
220
What conditions turn our Resident Microbiota to an opportunistic pathogen?
1. Immune suppression
2. Stressful conditions
3. Introduction of resident microbiota into an unusual location
221
Every pathogen must have at least one reservoir. A reservoir is the ___ of a pathogen or the____ ____ of a pathogen. A reservoir is a place for the pathogen to survive, multiply (reproduce), and to stay before and after infecting a host. Some pathogens have more than one reservoir.
Every pathogen must have at least one reservoir. A reservoir is the **source** of a pathogen or the **primary habitat** of a pathogen. A reservoir is a place for the pathogen to survive, multiply (reproduce), and to stay before and after infecting a host. Some pathogens have more than one reservoir.
222
Zoonoses
Diseases that spread from another animal host to humans
223
Zoonoses is acquired through various routes:
1. Direct contact with animals or their waste
2. Eating affected animals
3. Blood-sucking anthropods
224
Common portals of entry
Skin, Mucous Membranes, Placenta, and Parenteral (blood)
225
The portals of exit are the same as portal of entry (Skin, Mucous Membranes, Placental, and Parenteral) EXCEPT:
Placental
226
(Portal of entry)- Majority of infections come from
Mucous membranes
227
Signs are ____ manifestations of disease ____ or ____ by others
Signs are **objective** manifestations of disease **observed or measured** by others
228
Symptoms are ____ characteristics of disease that are ___ by the patient
Symptoms are **subjective** characteristics of disease that are **felt** by the patient
229
Examples of symptoms
pain, headache, fatigue, nausea
230
Examples of signs
fever, vomiting, a rash
231
Hereditary
Caused by genetics
232
Iatrogenic
Caused by a medical procedure
233
Nosocomial
Caused by the hospital (hospital aquired)
234
Idiopathic
Unknown cause
235
Congenital
Present at birth
236
Infectious
Caused by a pathogen, bacteria, etc.
237
The CDC (Center for Disease Control) provides weekly reports listing the ______and _________ for numerous diseases. Incidence is the _____ of ____ ____ whereas Prevalence is the _____ ____ of cases. One of the most important diseases in these reports is for ____- ______ _____ _____.
The CDC (Center for Disease Control) provides weekly reports listing the **INCIDENCE and PREVALENCE** for numerous diseases. Incidence is the **number of new cases** whereas Prevalence is the **total number of cases**. One of the most important diseases in these reports is for **HAI’s- Healthcare Associated Infections.**
238
Endemic disease
Disease is constantly present (stable)
239
Epidemic disease
Larger number of people affected in a short period of time
240
Epidemic disease
Larger number of people affected in a short period of time
241
Pandemic disease
Occurring in multiple countries within a short period of time
242
Structural barrier-
Microorganisms that form our normal microbiota only live on the surface of our body (it can be either external or internal surface), this body surface is made up of _____ ____. There are two main types of epithelial surfaces: the ____ and the ____
Microorganisms that form our normal microbiota only live on the surface of our body (it can be either external or internal surface), this body surface is made up of **epithelial cells**. There are two main types of epithelial surfaces: **the skin and the mucous membrane.**
243
(1) The first kind of mechanical barrier is due to the ______ ______ of the epithelial cells lining the surfaces of ____ and ____. These epithelial cells can produce mucus that entraps microorganisms. Cilia on epithelial cells constantly move this mucus toward the mouth, where the mucus along with the trapped microorganisms is swallowed and eliminated
The first kind of mechanical barrier is due to the **mucociliary movement** of the epithelial cells lining the surfaces of **nose and throat**. These epithelial cells can produce mucus that entraps microorganisms. Cilia on epithelial cells constantly move this mucus toward the mouth, where the mucus along with the trapped microorganisms is **swallowed** and eliminated
244
(2) The second kind of mechanical barrier is due to the movement of our body fluids (such as blood, urine, tears, semen…..etc). For example, in the ____, the rapid flow of urine washes away most microorganisms that happened to establish residence on the lining of urethra. Another example would be our ___ washing microorganisms off the conjunctiva
(2) The second kind of mechanical barrier is due to the movement of our body fluids (such as blood, urine, tears, semen…..etc). For example, in the **urethra**, the rapid flow of urine washes away most microorganisms that happened to establish residence on the lining of urethra. Another example would be our **tears** washing microorganisms off the conjunctiva
245
Biochemical barrier (or chemical barrier)-
Biochemical barriers are..
chemicals produced by cells on the surface of the human body against microorganisms
246
Examples of biochemical barriers
- Keratin
- Perspiration
- Lysozymes
- Sebum
- Acids (HCl)
247
Genetic barrier-
Some hosts are..
genetically immune to the diseases of other hosts
248
Genetic barrier, Species Specific Exs
- HIV (human) vs FIV (felines
- Ebola virus
- Heartworms
249
Innate immunity
- Present and functional at birth
- Nonspecific
- No memory
250
Adaptive immunity
- Present and nonfunctional at birth
- Specific
- Memory
251
Our body’s second line of defense against microbial invasion or infection has to do with our body's natural, nonspecific immune responses. These immune responses include four components:
inflammation, phagocytosis, interferon, and complement
252
Inflammation can be identified by four classic symptoms: _______________. A fifth symptom, the loss of ____, is often added to these classic symptoms but can be attributed to the swelling and pain.
Inflammation can be identified by four classic symptoms: **redness, heat, swelling, and pain**. A fifth symptom, the loss of **function**, is often added to these classic symptoms but can be attributed to the swelling and pain.
253
Goals of inflammation:
- Remove the agent causing inflammation
- Keep damage localized
- Allow it to heal
- Alert adaptive immunity
254
3 sequential stages of inflammation (and local or systemic):
Vascular Changes (local)
Edema/Swelling (local)
Fever Development (systemic)
255
What does interferon do?
Inhibits the reproduction/synthesis of the viruses
256
Interferons are released by a cell once infected to
**protect neighboring cells**
257
Actions of complement / 3 different groups of protein:
- C3a/ C5a
- C3b
- C5 - C9
258
C3a/ C5a
chemotaxis
259
C3b
opsonization
260
C5-C9
Membrane Attack Complex (MAC)- actually kills the microbe by punching holes in it, causing lysis
261
5 sequential stages of phagocytosis:
1. Chemotaxis
2. Ingestion
3. Fusion
4. Killing
5. Elimination
262
**Recognition** of invader due to signal molecules on the microbe surface
Chemotaxis
263
Ingestion- membrane extensions surround microbe forming a ____
membrane extensions surround microbe forming a **phagosome**
264
Fusion-______ fuses with phagosome creating a _______
**lysosome** fuses with phagosome creating a **phagolysosome**
265
In both types of immunity (humoral/cell-mediated), the attack of the pathogen occurs as a result of the ______ of an ______. The antigen is a molecule that triggers an immune response. The antigen is usually a surface protein however it could also be a carbohydrate or a lipid. There are **3 basic categories of antigens:**
As a result of the **recognition of an antigen**
- Exogenous antigens
- Endogenous antigens
- Autoantigens
266
Exogenous antigens
found outside a body's cells (including toxins and other components of microbial cell walls, membranes, flagella, pili)
267
Endogenous antigens
produced by microbes that reproduce inside a body's cells
268
Autoantigens
self made antigens
269
2 types of lymphocytes and what they're responsible for
T Lymphocytes (T cells)- responsible for **cell-mediated immunity** which is a response against **intracellular** pathogens
B Lymphocytes (B cells)- responsible for **humoral immunity** which is a response against **extracellular** pathogens
270
Important points- T Cell Activation:
- Infected cells are displaying _____ _ ______ antigens
- APC displays both _____ __ and ____ __
- Interleukin ____ produced by APC causes Th to become ___
- Interleukin ___ produced by both Th1 and T8- activates ___
- Infected cells are displaying **MHC 1 endogenous** antigens
- APC displays both **MHC 1 and MHC 2**
- Interleukin **12** produced by **APC** causes Th to become **Th1**
- Interleukin **2** produced by both Th1 and T8- activates **T8**
271
Components of T cell Activation
Cytotoxic T
Helper T
Memory T
Regulatory T
272
Types of lymphocytes used in B cell activation
B lymphocytes
Plasma cells
Helper T
Memory B
273
Key points of B cell Activation:
- _____ (both dendritic and B cell) displays _____
- Interleukin ___ causes Th to become ___
- Interleukin __ from Th also activates ______ to become _____ ____
- _______ made by plasma cells attack _______ antigens
- **APC's** (both dendritic and B cell) displays **MHC 2**
- **Interleukin 4** causes Th to become **Th2**
- Interleukin **4** from Th also activates **B cell** to become **plasma cells**
- Antibodies made by plasma cells attack **exogenous** antigens
274
Remember that B cells are responsible for humoral immunity, which is the
production of **antibodies** to attack extracellular epitopes (exogenous antigens)
275
5 types of antibodies
IgG
IgA
IgM
IgE
IgD
276
IgM
1st antibody produced; acute
277
IgG
most common and longest lasting; chronic
278
IgA
associated with body secretions; mucous membranes
279
IgE
involved in response to parasitic infections & allergies
280
A child has been infected with pinworms
IgG
281
Got the rabies vaccine a year ago
IgG
282
Just got coughed on from a person with the flu
IgM
283
4 functions/mechanisms of attack for antibodies
Phagocytosis
Lysis
Agglutination
Neutralization
284
The molecule that triggers an immune response
antigen
285
The antibodies that are produced by plasma cells come in a variety of different forms. The basic structure is a Y shaped molecule composed of __ heavy chains and ___ light chains. Each chain has a ______ region on it that creates an _______ ______ _____ that is ______ for each specific ______. The stem of the Y shaped antibody has some variation that is the premise for the difference between the types of antibody produced.
The antibodies that are produced by plasma cells come in a variety of different forms.The basic structure is a Y shaped molecule composed of **2 heavy chains and 2 light chains**. Each chain has a **variable** region on it that creates an **ANTIGEN BINDING SITE** that is **unique** for each specific **epitope**.
286
On the antigens are variable regions called ______. The epitopes have variable shapes, sizes, and complexity. It is the epitope that the immune system recognizes when mounting an attack against the pathogen. Epitopes are only recognized by adaptive immunity cells when carried on _____
Epitopes
MHCs
287
Epitope definition
3-dimensional regions that recognize antigens
288
Epitopes are recognized by the lymphocytes when displayed as
Major Histocompatibility Complex (MHC) proteins
289
Function of MHCs: ______ and _____ ______ for presentation to _____ ____
Holds and positions epitopes for presentation to immune cells
290
Cells that presents the epitope to the lymphocyte is called an
Antigen Presenting Cell (APC)
291
MHC 1
- Present on all nucleated cells
- Fixed cells (stationary, not moving around)
292
MHC 2
- Wandering cells with a nucleus
- Only present on APCs
293
MHC 2s include
macrophages, dendritic cells, and B cells
294
Autoantigens are displayed as
self MHC's
295
Endogenous and exogenous antigens are processed into ____ proteins to display _____ ______
Depending on the cell, these can be either ____ __ if a nucleated fixed cell, or ____ _ and ____ __ if an _____ ____ ____
are processed into **MHC** proteins to display **foreign epitopes**
Depending on the cell, these can be either **MHC 1** if a nucleated fixed cell, or **MHC 1 and MHC 2** if an **antigen presenting cell**
296
The interaction between leukocytes and dendritic cells and between different leukocytes requires ________ Costimulation is a result of the surface molecules on each of the cells as well as the release of important chemical molecules. These chemical molecules are referred to as _______
The interaction between leukocytes and dendritic cells and between different leukocytes requires **COSTIMULATION**. Costimulation is a result of the surface molecules on each of the cells as well as the release of important chemical molecules. These chemical molecules are referred to as **CYTOKINES**
297
Example of a cytokine and what it does
Interleukins (ILs): signal among leukocytes
298
Remember that T cells are responsible for cell-mediated immunity, which is the..
attack of infected cells
299
As a means of providing protection against pathogens not yet exposed a person can receive a _________, otherwise known as an immunization. The ________ that is administered is intended to be a ______ ______ of the pathogen so as to introduce the individual to specific foreign antigens/epitopes.
As a means of providing protection against pathogens not yet exposed a person can receive a **VACCINATION**, otherwise known as an immunization. The **VACCINE** that is administered is intended to be a **harmless version** of the pathogen so as to introduce the individual to specific foreign antigens/epitopes.
300
What's the goal of vaccines?
To provide the individual with **memory** cells against that epitope
301
What can measure the effectiveness of a vaccine?
a titer
302
Titer:
- measures _______ ______in blood serum for a specific ______
- serum being tested is serially diluted and tested for _________ activity
- ______ dilution of serum gives a positive reaction to the titer
- measures **antibody levels** in blood serum for a specific **antigen**
- serum being tested is serially diluted and tested for **agglutinating** activity
- **highest** dilution of serum gives a positive reaction to the titer
303
Basically, the titer is a reflection of _______ The actual antibody level is generally not protective against infection but instead represents the presence of ______ ______
Basically, the titer is a reflection of **protection**. The actual antibody level is generally not protective against infection but instead represents the presence of **memory cells**.
304
Attenuated vaccine
- modified live
- uses pathogens with reduced virulence
- ex: measles, chicken pox
305
Inactivated vaccine
- killed
- often contains adjuvants (chemicals added to increase antigenicity)
- ex: rabies, polio
306
Toxoid vaccine
- chemically/thermally modded toxins to stimulate active immunity
- most useful for some bacterial diseases with **exotoxins**
- ex: tetanus
307
What do toxoids work against?
exotoxins (not attacking epitopes like others)
308
Subunit vaccine
- Only **a portion of microbe** is used in vaccine
- ex: whooping cough, HPV
309
mRNA vaccine
- Only **a portion of mRNA** is used in vaccine
ex: covid
310
T/F: Gram-negative bacteria have 2 cell walls
False
311
Flatworms and ringworms are
small multicellular organisms
312
Where is the electron transport chain located in microbes?
Cell membrane
313
What attaches a flagellum to the cell membrane?
Basal Body
314
Fermentation is considered to be
substrate level fermentation
315
The final electron acceptor for fermentation is ___ ___, but if it's anaerobic it's _____ ___
1. Pyruvic acid
2. Inorganic molecule
316
2 things selective toxicity mean
1. No harm to host
2. Only one mechanism of action
317
Blocking PABA disrupts metabolism of ___ ___
folic acid
318
What is quorum sensing?
Communication between microbes
319
Tick transmitted diseases are best treated with what group of antibiotics?
Tetracycline
320
T/F: Most illnesses in humans are caused by a single bacterial species
False
321
The R plasmid would most likely contain genes for:
Penicillinase
322
A microbe that is capable of making organic molecules from CO2 is an
autotroph
323
Teeth discoloration
Doxycline
324
Joint damage
Ciprofloxacin
325
How does using ozone work to sanitize water?
Creates free radicals that denature proteins
326
Which is true of an Hfr prokaryote?
Transfers entire chromosome to the recipient
Converts recipient into an Hfr cell
Has an F plasmid
None of the above
None of the above
327
May cause mild disease
Attenuated
328
Targets a flagella
Subunit
329
Inactivated
Adjuvant
330
Translation of proteins
mRNA
331
Tetanus is a
toxoid
332
In cell-mediated immunity, what will be used on APCs
Both MHC 1 and MHC 2
333
The surface of which of the following is normally axenic:
Intestines
Nose
Blood
Skin
Blood
334
An individual who is recovering from the flu should still stay home to prevent spread because they're still considered a
convalescent carrier
335
Protein molecules that allow resident microbiota to attatch to epithelium surface
Adhesins
336
When a virus leaves a cell, taking a portion of the cell membrane with it:
Budding
337
An antiphagocytic factor that kills WBCs
Leukocidin
338
T/F Viruses synthesize and assemble envelopes prior to release from a cell
False (not envelopes)
339
Hepatitis C traveling in the blood to infect liver cells will have ____ ____ on the surface
exogenous antigens
340
T/F: Cytotoxic T cells attack infected cells displaying MHC 1 exogenous antigens
False- it should say endogenous antigens
341
What is responsible for conjugation?
Fertility gene (F factor)
342
What's the difference between fertility in a plasmid vs in the chromosome?
If it's F+, the recipient who was F- becomes F+ and no other chromosome gets transferred
If it's Hfr, they stay F-, but the other chromosome does transfer
343
a small DNA molecule that replicates independently of the other chromosomes often carrying information required for replication.
plasmid
344
Failure to add iodine
All bacteria appear G-
345
Failure to apply decolorizer
All bacteria would appear G+
346
Failure to apply safranin
G- is colorless and G+ appears purple (unaffected)
347
Reversal of crystal violet and safranin stain
All bacteria would appear G+
